Another critical step is gaining scientific consensus on the triggers
(i.e., the points at which a concern is indicated and a higher level of
testing is needed). The retrospective analyses will also be used to
refine or confirm the ASCA proposed triggers for test decisions.  Once
the analysis is complete, EPA will be able to complete draft guidance on
testing.  The analyses and guidance are planned to be subject to SAP
review and public comment in 2008.

Another essential step is testing how the ASCA scheme works in practice.
There are plans to conduct several case studies using the ASCA tiered
testing proposal.  From these case studies, EPA will be able to assess
the laboratory testing feasibility of such a complex study and to
evaluate the ability of the approach and its parameters to characterize
known toxicants and address risk assessment needs. Based on early
scientific reviews, EPA scientists are already working on improvement of
the ASCA tiered testing approach.  EPA will consider the results of the
SAP review of the retrospective analyses and draft guidance, issues
raised by stakeholders, and the case studies, in determining what
revisions to current data requirements and testing guidelines may be
appropriate.  As the science issues are adequately vetted and crucial
questions resolved, EPA intends to promulgate the appropriate regulatory
changes on a timely basis.  In the meantime, the existing regulations
provide flexibility to implement any updated, new or novel testing
schemes, on a case-by-case basis, as appropriate, until the changes are
codified.  Case-by-case determinations would be made in consultations
with the Agency without the necessity of the waiver process.  It should
be noted that ACSA is only one proposal that EPA will consider in
improving the risk assessment process of environmental chemicals.

	Other relevant activities to consider include the  National Academy of
Sciences (NAS) recommendations on Toxicity Testing and Assessment of
Environmental Agents (expected in 2007; Project ID BEST-U-03-08-A),
OECD’s Integrated Approach to Testing and Assessment, as well as
predictive toxicity tools (QSAR, “-omics,” etc.) developed by
EPA’s Office of Research and Development’s (ORD) Computational
Toxicology Program (www.epa.gov/comptox).

	Before considering regulatory changes to reflect the results of
EPA’s consideration of ACSA, NAS, and other recommendations, the
Agency will develop scientific position papers on the new approach and
recommendations for internal and external review; the latter includes
review by the FIFRA Science Advisory Panel and opportunities for public
comment.  External peer review and acceptability by other national and
international regulatory authorities are crucial before implementation
of any new testing paradigm and data requirements. Harmonization with
the data requirements of these same authorities is also an important
factor.  Other countries currently require studies that were omitted in
ACSA; this could pose significant problems for registrants if a
harmonized approach is not adopted world-wide.  The proposed rule was
concerned with codifying the data requirements in 40 CFR part 158.  Data
requirements identify the kinds of questions registrants must address
about the potential hazards and levels of exposure.  Test guidelines
describe test methods that may be used to perform a study to answer the
questions the registrants must address.  Test guidelines are developed
and updated during a process separate from updating data requirements.
Therefore, the commenters’ suggested changes to test guidelines will
be forwarded to the respective divisions for review.  Any possible
changes in test guidelines will be presented to the FIFRA SAP and open
to public comment before adoption.

	At the PPDC meeting held November 8-9, 2006, the EPA/PPDC Alternative
Testing Project reported on the adoption of non-animal methods to
replace the Draize methods for acute eye and skin irritation for
antimicrobial cleaning projects only.  The purpose of the project is to
allow EPA reviewers to make Toxicity Category and Product Labeling
decisions based on these alternative assays.  Eight companies have
submitted data and will assist the project in various ways.  The
Background Review Document is expected to be submitted to ICCVAM in
Spring 2007 with EPA consideration of the Interim Science Policy for
non-animal assays in Summer/Fall 2007.

Discussion of Comments on Ecological Effects Data Requirements (Subpart
G)

A.  Terrestrial Wildlife

1.  Acute Oral Toxicity Test with a Passerine Species

The Agency proposed a requirement for an additional avian acute oral
toxicity study.  The second acute oral study is to be conducted on a
passerine species (i.e. red-winged blackbird) as a requirement to
support all outdoor uses, including residential outdoor uses.  The other
avian acute oral study is to be conducted on either the mallard duck or
the bobwhite quail, which has been standard policy.  This revision of
the avian acute toxicity data requirement elicited a significant number
of comments, as compared to comments about other proposed changes in the
data requirements for terrestrial organisms.  The comments not only
concerned the addition of a passerine species to the avian acute oral
data requirement, but also test note number 4 which specifically named
the red-winged blackbird (Agelaius phoeniceus) as the preferred
passerine species.

COMMENT   Four commenters (# 112,  # 113, # 120  and # 125) questioned
the need for another avian acute oral toxicity study, as the accepted
policy has historically been to require only one avian acute oral study.
 Commenters #113 and # 146 also indicated that there was confusion about
the addition of the passerine test, and interpreted the requirement as
either testing three species or requiring a passerine test in lieu of
the commonly required bobwhite or mallard tests.

RESPONSE   The Agency has always required testing on either bobwhite or
mallard (one species is required for LD50 testing).  The new requirement
calls for testing on either bobwhite or mallard plus the passerine.
There has been no proposal for requiring testing for three species.
SEQ CHAPTER \h \r 1 The Agency, in 1993, consulted the Science Advisory
Panel (SAP) on the subject of acute toxicity testing of birds.  The SAP
indicated that the lack of testing of passerines represented a
potentially significant data gap.

COMMENT   One commenter (#128) stated that two bird species should
always be tested for acute oral effects and expanded to 3 species for
compounds with acute oral LD50s of 500 mg/kg or less.

RESPONSE   The Agency can see the utility for expanding the number of
tests to three species to address uncertainty about intraspecies
sensitivity.  However, the Agency believes that such an expansion should
be based on the results of appropriate ecological risk assessment
results and any need for addressing uncertainties that limit risk
management decision-making.  The Agency is keeping the number of tested
species for the avian acute oral data requirement to two species in this
rulemaking.

COMMENT   Three commenters (#122, # 113,  #112) requested that the
Agency consider other passerine species and provide a list of
recommended species to the regulatory community.  One concern raised by
two commenters (#142 and #112) was the protection of the red-winged
blackbird under the Migratory Bird Treaty Act and the requirement to
obtain permits from the FWS to collect live red-winged blackbirds.
Additionally commenter142 indicated that state agencies may also require
state permits in addition to the federal ones.  Their research
experience showed that the permit issue caused significant logistical
problems.

COMMENT   Commenter 142 also cited human health and ethical reasons for
not using the red-winged blackbird in a laboratory setting.  The human
health issue relates to the possible transmission of avian-borne
diseases from wild-caught birds to their lab-reared birds and to the
people who must handle the birds on a daily basis.  They recommend that
commercially available species as the zebra finch be used for passerine
tests, and the tests should be designed on a case-by-case basis.

COMMENT   Commenters #124 and #137 also asked for increased flexibility
in their choice of the test species, by citing the difficulty in
obtaining sufficient numbers of the birds for a toxicity study and the
difficulty in maintaining this species in a laboratory facility.  Both
commenters cited the USGS Breeding Bird Survey,
http://www.mbr.pwrc.usgs.gov/bbs/htm03/trn2003/tr04980.htm which
presents data that populations are declining in North America.  Both
commenters stated that they preferred that the Agency continue its
policy of extrapolating the data from the mallard and bobwhite acute
studies to passerine species in its risk assessments.  They both
continued that wild species should only serve as laboratory test animals
“when absolutely necessary”, when extrapolation does not
significantly reduce uncertainty.  Commenter #124 proposed an alternate
version of proposed test note 4:

Data are preferred on mallard or bobwhite quail for all uses.
Additional species may be tested on a case by case basis to reduce
uncertainty about the toxicity of the chemical to wild species.

RESPONSE   The Agency selected the red-winged blackbird as a test
species because of (1) its prevalence in agroecosystems, (2) its
demonstrated use in avian toxicity testing with pesticides, and (3) the
availability of an existing data set to compare its sensitivity with
other species and provide a starting database for comparison of toxicity
across pesticides.  The guidelines will be modified to include the need
for a passerine species, with the red-winged blackbird listed as one of
the preferred species, rather than an explicit requirement for
red-winged blackbird testing.  Therefore, if the red-wing blackbird is
not available, a different species is to be proposed for use.  The
Agency will revisit the issue of an acceptable species list with this
goal in mind.  Testing protocols may list other species upon
reconsideration of this issue.

The Agency’s risk assessment process makes use of the most sensitive
species tested.  In addition, refinements of the risk assessment may
also consider the distribution of interspecies sensitivity.  More than
one tested species allows for consideration of interspecies sensitivity
and testing of a passerine addresses concerns that broad, untested avian
taxa may be more sensitive that previously required mallards and
bobwhites.

COMMENT   The Agency received two comments that the requirement for an
acute toxicity test with a passerine species should be based on the
results of the acute oral data from the mallard or the bobwhite,
whichever was tested.  One commenter (#113) stated their position that
an additional test with a passerine species could be justified if the
test substance were significantly toxic to either of the other test
species; but the requirement should be conditional at most.
Alternatively, the other commenter (#82) stated that the passerine study
may not be needed if the test substance were practically non-toxic to
the other test species.  This second commenter also recognized that
passerines are frequently more sensitive than the bobwhite and mallard,
and stated that they could support the requirement for outdoor use.  The
requirement could be aligned with the toxicity level from the acute
study with either bobwhite or mallard.  (They proposed an LD50 range of
<500 to 1000 mg/kg-bw).

RESPONSE   The Agency acknowledges that passerines can often be more
sensitive than the mallard or bobwhite and so has not established
conditions for requiring the testing on the basis of toxicity in either
mallards or bobwhite.  As noted previously, currently testing occurs on
either bobwhite or mallard (one species is required for LD50 testing).
The new proposal requires testing on either bobwhite or mallard and the
passerine (two species are required for testing).  There has been no
proposal for requiring testing for three species.

COMMENT   Two commenters (# 125, # 133) asked what data the Agency used
to support the contention that passerine species are less tolerant to
pesticides than larger species.  They also asked what data the Agency
will gain from the passerine test.

RESPONSE  The Agency’s concern is not necessarily that passerines are
more sensitive than larger species, but that passerines represent a
large number of North American species and, when tested, have proven to
be often, though not exclusively, more sensitive than non-passerines.
The Agency, in 1993, consulted the SAP on the subject of acute toxicity
testing of birds.  The SAP indicated that the lack of testing of
passerines represented a potentially significant data gap.

Schafer and Brunton (1979) published a summary of comparisons between
species.  In ranking the LD50 values for six species tested (4
Passeriformes, 1 Columbiformes, and 1 Galliformes) with 36 pesticides,
the red-winged blackbird was often the most sensitive species tested.
For the average LD50 over all chemicals tested, red-winged blackbird was
the most sensitive of the species tested.  Reviewing the available
literature and their own test results, the authors concluded that
sufficient data exist to suggest that mallards and bobwhite quail are
poor indicators of acute and subacute sensitivity and are poor
indicators of the sensitivity of most North American bird species.

In comparing the results of individual species (3 Passeriformes, 4
Galliformes, and 1 Anseriformes) testing with extrapolated lower bound
limits to intraspecies sensitivity distributions for up to 67 chemicals,
the red-winged blackbird acute effects endpoints more consistently were
ranked near the 5th percentile than any other species tested.

Schafer, E.W. and R.B Brunton.  1979.  Indicator species for toxicity
determinations: Is the Technique usable in test method Development?  In:
Vertebrate Pest Control and Management Materials, ASTM STP 680, J.R.
Beck, Ed., ASTM, 1979, pp. 157-168

Mineau, P., A. Baril, B.T. Collins, J. Duffe, G. Joerman, and R. Luttik.
 2001.  Pesticide acute toxicity reference values for birds.  Rev.
Environ. Contam. Toxicol.  170:13-74.

COMMENT  The Agency also received a series of comments from the EU (#56)
about the passerine data requirement.   The EU stated that assurance
that EPA will not base a risk assessment on a single species which might
be more sensitive or less sensitive as compared to other species is not
sufficient reason to require this additional test.  They contended that
the use of scientifically sound extrapolation factors in the risk
assessment process can account for this type of uncertainty.

RESPONSE   The Agency agrees that it should consider scientifically
valid extrapolation factors, where data are available to support their
development.  However, given the extremely limited number of species
usually tested within given taxonomic groups, the total lack of test
data in other taxonomic groups, and the recognition that such data
limitations are further compounded by the likelihood that extrapolations
are unstable across pesticide mechanisms of action, the Agency is
concerned that existing data may only be suitable for establishing
extremely conservative extrapolations at the screening level.  The
Agency believes that adding the passerine test to its suite of avian
toxicity studies will provide a more robust risk assessment than using
conservative extrapolation factors.  Additional testing in the future
will serve as a basis for a scientifically more robust evaluation of
potential extrapolation factors.

Four additional comments submitted by the EU and the Agency responses to
each comment are:

COMMENT 1.  Delete additional passerine test and use a science-based
assessment factor.

RESPONSE   In 1996 the SAP recommended inclusion of passerine species
because of the recognition that such birds may be more sensitive than
other tested species. Though passerines have been shown to be more
sensitive than other tested species, the sensitivity relationship is
variable across pesticides.  To date, OPP does not have a
screening-level assessment factor to account for this uncertainty.  The
subsequent issue is, if application of some generic uncertainty factor
were applied and screening risk assessments “fail”, what additional
course of refinement on the effects is possible without additional data?

COMMENT 2. Testing on a passerine species (i.e., redwing blackbird)
from a world wide perspective is a strange species to choose as it is
only found in northern America and difficult to raise in captivity.

RESPONSE   The red-winged blackbird is found in a variety of North
American agroecosystems, and there exists background toxicity data for a
variety of pesticides.  This allows for any comparisons with existing
tested pesticides (if needed) and allows for an ecologically relevant
risk assessment effects endpoint for the area in which most Agency
pesticide risk assessments are conducted.  However, the Agency is open
to consideration of additional passerine species as alternatives to the
red-winged blackbird.

COMMENT 3. The document is not clear how much additional avian
effects’ testing is needed.

RESPONSE   The preamble in the final rule clarifies issues raised by
several commenters regarding other avian testing requirements, such as
the reproduction studies and the field testing.  Additionally, the test
notes for the avian data requirements in Subpart G of the final rule
were rewritten for clarity.

COMMENT 4. The international community is aiming to withdraw the acute
avian oral toxicity study.  Why propose additional testing with an
obsolete test guideline?

RESPONSE   Current risk assessment procedures for the evaluation of
listed species require knowledge of the dose/response relationship.  In
addition, advancement of risk assessment to Level 2 techniques uses the
dose - response relationship for acute oral toxicity studies to
establish acute tolerance values for modeled individual birds.
Alternatives to the acute oral dose study have, to date, not empirically
demonstrated an ability to establish dose - response relationship
parameters equivalent to those established using the current toxicity
protocol.

COMMENT   One commenter (#120) stated that a laboratory study with
passerine birds is not technically feasible.

RESPONSE   The Agency does not agree with the comment.  Canaries have
successfully been used as test animals in acute toxicity testing.  Refer
to EXTOXNET Pesticide Information Profile for Triadimefon in which
canary LD50 values from Kidd, H. and James, D. R., Eds. The
Agrochemicals Handbook, Third Edition. Royal Society of Chemistry
Information Services, Cambridge, UK, 1991 (as updated) are provided.
The website for this document is:

http://ace.orst.edu/cgi-bin/mfs/01/pips/reflist8.htm

To summarize, based on the comments, the Agency deleted the red-winged
blackbird as the only acceptable passerine species for an additional
avian acute oral toxicity study.  However, the passerine acute oral
study is still required, in addition to one with either an upland game
bird or a waterfowl species.  The Agency will consider alternative
species submitted by the public or a registrant, as long as the
alternative species meets the criteria in the acute oral toxicity
guideline.

2.  Avian Dietary Study

COMMENT   Commenter #56 questioned the value of continuing to require
the avian dietary study.

RESPONSE   The Agency wants to maintain this study to determine the role
dietary intake plays in the sensitivity of birds exposed over several
days to a pesticide-contaminated diet.  We note that the EU continues to
work on the design of the avian dietary study with the US and other
countries through OECD.

3.  Japanese quail

COMMENT   The Agency received two comments regarding the use of the
Japanese quail as a test species in the acute toxicity test and in the
reproduction test.

COMMENT   One commenter (#56) stated the Japanese quail should be
accepted for acute toxicity testing.

RESPONSE   The Agency addressed the issue of Japanese quail when it
submitted the following to OECD on March 24, 2003.

"The Japanese quail should not be listed as a preferred test species.
Many years of domestication and artificial selection in this species may
have affected the response of this species to chemicals.  Also, a
species comparison of species sensitivity done for the 1994 Pensacola
meeting showed that the Japanese quail was significantly less sensitive
than the northern bobwhite in the dietary test.  Although this
difference was not found for the acute oral LD50's, it still indicates
that these two species respond differently to toxicants.  In addition,
the EPA has a long history of testing with the bobwhite and has
accumulated a large database of acute toxicity results for this species.
 Using another test species would increase uncertainty of comparison of
toxicity and risk among chemicals."

COMMENT   Another commenter (#128) wants the Agency to harmonize with
OECD regarding using the Japanese quail as an alternate for the bobwhite
quail in reproduction testing.

RESPONSE   At this time, the Agency has not harmonized with OECD on the
use of Japanese quail for reproduction testing because of concerns over
the high degree of domestication of the species and the extremely high
rate of reproduction that is poorly representative of North American
species.  However, the Agency is still actively considering the species
use in multiple generation reproduction testing because of laboratory
logistical issues associated with such long-term tests and lengthy
intergenerational times for other species.

4.  Avian toxicity endpoints

COMMENT   The FWS, (#146) continues to encourage the Agency to continue
to expand the endpoints evaluated in avian toxicity studies to include
behavior, enzyme levels, and other physiological, biochemical, and
morphological characteristics.

RESPONSE   The Agency has committed to considering an expanded suite of
sublethal effects.  However, there should be clear and reasonable
relationships between such measurement endpoints and Agency risk
assessment endpoints related to survival and fecundity of individuals.

5.  Avian reproduction

COMMENT   The Agency received two comments from one correspondent (#120)
stating that the need for an avian reproduction test should be based on
the pesticide’s properties.  The first comment stated that the testing
should be waived when there is neither evidence of toxicity from oral or
dietary routes nor evidence suggesting that such effects are of concern.
 The second comment stated that reproduction testing should not be
required for compounds that break down rapidly, partition rapidly in
aquatic systems, or do not bioaccumulate in aquatic species that are
potential food sources for some avian species.

RESPONSE   The Agency does not agree with the first comment.  Adverse
effects on avian reproduction can occur at levels of exposure several
magnitudes lower than those that can cause acutely toxic effects.  With
regard to the second comment, existing avian reproduction testing
involves a study that is some 21-weeks in duration.  The design of this
study, drafted in an era of organochlorine pesticides, reflects a
concern at the time for allowing exposure periods long enough to reach
test animal tissue saturations.  However, this prolonged exposure period
may not be necessary for less bioaccumulative compounds.  Therefore, for
some chemicals the actual length of the exposure window may be
considerably shorter to elicit effects than the study would suggest.
This raises considerable uncertainty as to just what would be the
appropriate environmental persistence criteria that would be suitable to
evaluate whether a specific pesticide might pose a risk for reproduction
impairment.  Rapid partitioning in aquatic systems has little bearing on
whether a pesticide will pose a risk in terrestrial agroecosystems for
species not consuming aquatic organisms. Bioaccumulation is a concern
to the Agency; however, the Agency’s risk assessment also considers
dietary exposures from pesticide directly applied to vegetation and
invertebrates in the treated field or off-field through spray drift.
These exposures, at the very least, involve consumption of food items
impinging pesticide at the time of application, a situation where
bioaccumulation is not a critical factor.

COMMENT   Two commenters (#125, #133) questioned why organophosphate
(OP) insecticides are cited as the reason for requiring measurement of
effects on the egg.  They questioned if other pesticides that are now
used have also been linked with eggshell effects.

RESPONSE   The Agency maintains that reproduction studies involving both
bobwhite and mallard test species have shown eggshell effects in a
variety of pesticide classes including some OPs.  However, this endpoint
is not consistently the most or least sensitive of all endpoints
measured.

COMMENT   One commenter (#128) advocated the development of reproduction
tests with passerine species.  Their interest was based on the fact that
the current species used in this test, the mallard and the bobwhite, are
precocial species (birds that are born covered with feathers, able to
see and leave the nest soon after hatching).  Passerine species, which
are altricial (birds that are born naked and blind and depend on their
parents for food), may have significant behavioral responses to
pesticides different than those of the currently tested species.  These
responses could affect reproduction through factors as incubation
behavior and care of young.  They acknowledge that there presently are
no testing protocols for passerine species, but they encourage the EPA
to support the development of passerine reproduction testing with
species like the zebra finch or the house finch.

RESPONSE   The Agency believes that addressing the potential differences
in reproduction between passerines and other birds is scientifically
appropriate.  However, at this time, no protocols have been made
available to the Agency for such testing.  Given the challenges testing
labs are faced with for existing reproduction tests, protocols for
passerines will not be available for this edition of Part 158.

6.  Wild Mammal Testing

COMMENT   The Agency received three comments regarding the wild mammal
toxicity test and test note 7.  The first comment (#120) stated that
test note 7 was unclear, and they asked for more specific guidance as to
what avian or mammalian acute and subacute testing, fate characteristics
and use patterns could trigger this data requirement.

RESPONSE   The Agency evaluates the need for wild mammal toxicity on a
case-by-case basis.  The results of effects testing or fate testing
alone are not the causal factor in such a determination.  Rather, such
study requirements are based on whether, given the use pattern, effects
and fate profile, benefits, and current risk assessment, there is
sufficient uncertainty to preclude a determination of the risk/benefit
relationship.

COMMENT   The second commenter, # 124, stated that wild mammal studies
should only be triggered when the terrestrial risk assessment triggers a
potential concern based on mammalian endpoints generated in the
toxicology data package.  They proposed the following changes to test
note 7:

Data on wild mammal species may be required when a refined terrestrial
risk assessment triggers a potential concern for a given use pattern
based on laboratory toxicity endpoints and a refined exposure
assessment.  Consideration needs to be given to the potential for
exposure and the potential assessment endpoints that could be impacted.

COMMENT  Commenter # 137 proposed that test note 7 be revised to state
that data on a wild mammal species may be required when the terrestrial
risk assessment triggers a potential concern (acute RQ > 0.5; chronic RQ
> 1.0) for a given use pattern based on laboratory toxicity endpoints
and a refined exposure assessment.

RESPONSE   The Agency reiterates that there may be case-specific
information that would trigger the need for additional testing.  This
might include lines of information that suggest that available toxicity
data provide unsuitable surrogacy for a particular non-target species.
While the Agency will not be changing part 158 from what was proposed in
this regard, we will continue to consider more specific criteria over
time, and include those in later revisions to part 158 as appropriate.

7.  Acute Toxicity Studies with Reptiles

COMMENT   The Agency received one comment (#146) stating that effects on
reptiles still are inadequately addressed in this new regulation.
Continuing to use avian species, even with the addition of a passerine,
test is not adequate to assess risks to reptiles.

RESPONSE   The Agency will consider any peer-reviewed reptile testing
protocols for possible future addition in required testing.  Information
demonstrating a biologically significant difference in sensitivity or
exposure between birds and reptiles, which would suggest that bird risk
assessment is not adequately protective, can still be considered in
individual risk assessments.

8.  Field testing

The Agency received four comments regarding the data requirement for
simulated or actual field testing with terrestrial animals.

COMMENT   One commenter (#120) stated that the information provided in
the test note for this data requirement (proposed test note 8) was
nebulous and asked for clarification.

 RESPONSE   The Agency evaluates the need for field testing on a
case-by-case basis.  The results of effects testing or fate testing
alone are not the causal factor in such a determination.  Rather, such
study requirements are based on whether, given the use pattern, effects
and fate profile, benefits, and current risk assessment, there is
sufficient uncertainty to preclude a determination of the risk/benefit
relationship.

COMMENT   Two commenters (# 124 and # 137) stated that additional
testing, particularly with wild species in the natural environment,
should only be conducted when refined risk assessments indicate a
potential concern.  Risk based triggers ensure that these studies are
only performed when other tools and process have indicated that field
data is required to resolve uncertainties.

COMMENT   Commenter # 137 suggests that additional testing, particularly
with wild species in the natural environment, should only be done when
the refined terrestrial risk assessment indicates a potential concern
which they described as an acute RQ > 0.5 or RQ >> 1.0.  They believe
that using a risk-based trigger ensures that field studies are only
conducted when all other ecotoxicological tools and processes have still
left uncertainties that need to be resolved by a field study.

RESPONSE   The Agency concurs in part.  Field studies have traditionally
been performed to address uncertainties in risk assessments, especially
those risk assessments predicting environmental effects of concern.
However, setting a conditional requirement that triggers such studies
only when risk assessment tools predict adverse effects ignores the
possibility that lines of information may conversely point out
inadequacies of the existing tool to provide adequate protection.  In
such cases a prediction of no concern for environmental effects, with
attendant uncertainties, may trigger additional data development before
a risk management decision is reached.

COMMENT   Commenter # 124 proposed the following change to proposed test
note 8:

Higher tier testing may be required for a specific use pattern when a
refined risk assessment indicates a concern based on laboratory toxicity
endpoints and refined exposure assessments.

RESPONSE   The Agency concurred and changed test note 6 in the final
rule to the language submitted by commenter #124.

COMMENT   Commenter #146 stated that field testing can provide a more
realistic assessment of potential impacts to nontarget species that may
act in consort to affect an organism’s fitness and should remain a
data requirement.

RESPONSE   The Agency agrees with this comment that field testing can be
useful, if conducted with the requisite scientific rigor.  To this end,
the Agency has retained the existing field testing data requirements in
Part 158.

9.  TEP testing

A significant number of the comments the Agency received concerned the
confusion in the data table regarding the use patterns that would need
to be supported by TEP testing, in addition to testing with the active
ingredient.

COMMENT   Two commenters (#113 and # 146) stated that the proposed rule
did not clearly state when testing with end-use products would be
required.  Commenter #146 recommended TEP testing for all products with
potential aquatic or terrestrial nontarget exposure.

RESPONSE   The Agency evaluates the need for testing of TEPs on a
case-by-case basis.  In such evaluations, the Agency relies on available
lines of evidence such as published literature, 6(a)(2) data
submissions, European regulatory testing, and confidential statements of
formula.  The potential for non-target organism exposure to TEP would
naturally be a consideration as well.

COMMENT   Another commenter (#82) stated that a different protocol or
type of study (other than gavage) may be required to assess avian oral
toxicity of an end-use product, particularly a granular.

RESPONSE   The Agency acknowledges this, and on a case-by case basis,
requests for such testing are accompanied by discussions of appropriate
protocol adjustments.

COMMENT   A fourth commenter (#120) stated that the table in the
proposed rule for avian toxicity studies with TEP indicated that the
studies are required for all uses except greenhouse and indoor which are
conditionally required.  However propose footnote 3 indicates that
testing with TEP is conditional based of results of acute and dietary
studies.  Specific triggers are not identified and should be.  TGAI and
TEP should be separated indicating conditional requirements for TEP
testing.

COMMENT   Commenters # 124 and # 137 stated that TEP testing for avian
species should only be triggered when the nontarget terrestrial organism
is expected to encounter the intact end-use formulation or is expected
to use the formulation itself as a food source, and the risk of adverse
effects in such a situation is potentially high (RQ>0.5) based on
calculations using the toxicity of the TGAI.  Commenter # 124 proposed
that proposed test note 3 state that data using the TEP should be
conditionally required based on the results of the testing with the
TGAI, the potential for oral ingestion of the end use formulation, and
an acute RQ>0.5, based on the TGAI data.

COMMENT   Two commenters (#125, #133) stated that testing of TEP for
passerine effects will become burdensome and costly.  They asked who
will decide which product to test, and who will then monitor to see if
additional formulas need to be investigated?

RESPONSE   In light of the number of comments received on this issue,
and past experience that shows TEP testing has mainly been required for
granular formulations or other special situations, the conditional
requirement for formulation testing was removed from the data
requirements in the final rule.  It remains consistent with past policy
and may be required on a case-by-case basis.

10.  Use Patterns

Several comments indicated that there was confusion as to the
relationship between specific use patterns and the data needed to
support that use pattern.

COMMENT   One commenter (#124) stated that the dietary TGAI testing for
aquatic non-food residential uses should only be triggered when the
nontarget terrestrial organism is expected to be exposed in the
environment and the terrestrial acute risk assessment triggers a
potential concern based on acute oral test with the TGAI.  They proposed
the following change to proposed test note number 6:

For aquatic nonfood residential uses, if the TGAI acute avian risk
assessment indicates a significant concern for a given use, and there is
a potential for exposure, then an additional acute dietary test with
TGAI may be conducted using either bobwhite quail or mallards.

RESPONSE   The Agency removed use patterns such as aquatic residential
and consolidated all subdivisions under aquatic to simply “aquatic use
patterns” in the final rule.  The Agency did not change the number or
types of birds that must be tested for the dietary toxicity test.  All
aquatic uses require the dietary test with both the upland game bird and
waterfowl species.

COMMENT Commenter 146 asked that the Agency clarify the use of avian
testing for the aquatic non-food residential uses

RESPONSE   The Agency’s position is that avian exposure from labeled
uses is expected to be limited for aquatic non-food residential uses.
However, when data are required, these data will be used in development
of the avian risk assessment.

COMMENT  Two commenters (#125, #133) stated that presently a subacute
avian dietary study is required for domestic (residential) outdoors and
is conditionally required (CR) for indoor or greenhouse use patterns.
However, the proposed 158 rule shows that the dietary study is being
eliminated in favor of the acute oral study.  They do not understand
which of the two avian studies better portrays field situations.

RESPONSE   The Agency made the switch to requiring the avian acute oral
study for indoor uses and greenhouse uses based on the expectation that
acute oral toxicity studies may be more representative of conditions
involving any accidental environmental release associated with these
uses.

COMMENT   Commenter # 125 questioned why the avian reproduction study
is now required for residential outdoor and terrestrial uses.

RESPONSE   Birds can be exposed to pesticides on these sites during the
times when exposure may potentially affect a bird’s ability to
reproduce successfully.  The exposure period can occur prior to
egg-laying, when the adult is physiologically preparing to reproduce, or
during the actual egg-laying or nesting stages when the adult, eggs or
juveniles can be exposed.  Therefore, the avian reproduction study
provides data essential to determining risks to birds during this stage
of their life.

11.  Guidelines Not Finished

COMMENT   The Agency received seven comments from five commenters (#112,
#120, #123, #124, #137) that the 850 series of OPPTS guidelines for
ecological data, cited in proposed subpart E, only exist in draft form
and have never been established as final guidance documents.  The
general opinion was that EPA should not propose data requirements in the
absence of formal, established guidance.  Commenters # 112 and #120 also
stated that the lack of finalized guidelines would place an unfair
burden (cost) on the regulated community due to the lack of access to
the substance of the data requirements and potential revisions to the
ongoing drafts.  Commenter #56, the EU, stated that the Agency should
place more effort towards the development of a common approach based on
use of internationally agreed and validated test guidelines.  Commenters
#124 and #137 stated that the draft 850 guidelines do not meet “the
expectations of the USEPA Environmental Fate and Effects Division (EFED)
for the terrestrial and aquatic nontarget organism data packages.”
This statement is based on their reviews of EFED risk assessments.
Commenter #124 proposed that both guidance documents (850 series and 71
series) be noted in the data requirement tables until such time “that
the 850 series guidance is revised to reflect the EFED reviewers’
requirements for these toxicity studies.”

RESPONSE   The 850 series of guidelines is scheduled to be completed and
available to the public by late 2007.  Nonetheless, guidelines are
guidance documents only, and the promulgation of data requirements does
not depend on the availability of guidance documents.

Insects

COMMENT  The Agency received four comments (# 124, #125, #133 and #137)
stating that the conditions in proposed test note 26 of the proposed
rule for the field study requirement are too broad and that the
guideline for this study is vague.

RESPONSE   The Agency agrees that the definition for the term “field
testing” and the test criteria need to be clarified.  The intent is to
allow for additional testing to address a specific concern based on
effects noted in testing with bees or other terrestrial arthropods.
Field testing, in this context, would most likely be the type of testing
identified in the comment as “semi-field”, for example a tent or a
tunnel.  We also note that under item iii for proposed test note 26, the
word “terrestrial” was inadvertently omitted before the word
“arthropod”.  This was corrected in the final rule, so the sentence
in finalized test note 25 states “...studies with terrestrial
arthropods other than bees...”.

COMMENT   One commenter (#120) stated their belief that acute contact
toxicity study should be designated as CR for the aquatic uses.
Specific application methods could be indicated for further testing in a
footnote, while others such as directed applications or incorporation
into water, or formulation types such as granulars could be specifically
cited as examples of restricted exposure scenarios.

RESPONSE   The Agency agrees with the CR designation for the acute
contact toxicity test for aquatic uses. It was changed in the final
rule.  The acute contact toxicity study is a basic test designed to
provide hazard data on the intrinsic nature of the chemical.
Application methods or type of formulation are not determining factors
for the data requirement.  Therefore, these factors are not taken into
consideration with regard to requiring this study.

COMMENT   One commenter (#125) asked what residential uses are likely to
trigger the field test.

RESPONSE   The requirement for a field study with pollinators is
determined by weight of evidence information, and not so much by the use
pattern.  The field study can be required if other insect studies,
including any incident data, show an effect that cannot be further
investigated in additional laboratory testing.  Test note 25 in the data
table in the final rule provides the conditions under which this test
may be required.  As with other ecological effects field testing, the
registrants are strongly urged to contact the Agency prior to initiating
any field testing.

Aquatic Organisms

  SEQ CHAPTER \h \r 1 1.  Sediments

	The Agency received forty-three comments about the newly codified acute
and chronic sediment toxicity data requirements.  Most of the comments
concerned the conditions for requiring these tests (primarily proposed
test notes 23 and 24).  Some of the comments discussed risk assessment
issues.  As mentioned above the majority of the comments the Agency
received about the sediment toxicity data requirement concerned the
language of the test notes for the data requirements.  The commenters
cited not only the test notes, but also the sections of the Preamble
where the sediment data requirements were discussed in detail. More than
half of the comments focused on the triggers based on the Kd value and
the half-life value.

COMMENT  Two commenters (#124, #137) asked the Agency to justify a
statement in the Preamble regarding the  ability to assess risks from
sediment bound pesticides using only the water column data [
“…effects of sediment bound pesticides … on aquatic environments
cannot be accurately assessed from bioassays on compounds suspended in
the water column alone…” (X.B.2)]. The commenters referred the
Agency to use of the Equilibrium Partitioning Theory (EqP) that was
published by EPA (DiToro, et. al. 1991, Environ. Toxicol. Chem.
10:1541-1583) to estimate risks from sediment bound contaminants on
aquatic ecosystems.  They pointed out that EqP theory links water column
concentrations to sediment concentrations to allow the assessment of the
impact of bound pesticides.  They emphasized that the agency needs to
recognize that sediments are complex environments, and that it is often
difficult to characterize exposure in terms of the bioavailable
fraction; uncertainty is not necessarily reduced by performing sediment
toxicity studies.

RESPONSE   The Agency reiterates from the Preamble that lipophilic
compounds or hydrophobic chemicals can dissipate from the water column
but may still remain in the aquatic environment adsorbed to sediments.
Effects in the water column may be of short duration constituting acute
toxicity, while effects from the sediment/ pore water may show morbidity
and growth or emergence effects (e.g., Chironomus).  Sediment bound
compounds can differ significantly from compounds in solution, showing
different physical, chemical, and biological properties, chemical
partitioning, bioavailability, etc.  While the Agency can extrapolate
sediment toxicity by using EqP and water column toxicity values, this
cannot account for the complexity of sediment and pesticide
interactions.  Actual testing of spiked sediments will present a more
accurate depiction of possible risk to benthic invertebrates.

COMMENT   The same two commenters (#124, #137) also stated that sediment
toxicity studies should only be required when the Agency’s risk
assessment based on the water column toxicity data and the environmental
fate data indicate there is substantial uncertainty regarding potential
risks of the pesticide in the sediment layer of aquatic ecosystems.

RESPONSE   The Agency does perform an aquatic risk assessment that
includes a sediment component prior to requiring sediment testing.  The
Agency applies the EqP approach by using available water column toxicity
data and model derived sediment/pore water exposure values to estimate
risk.  With this approach the Agency extrapolates potential risk to
benthic, as well as other aquatic organisms.  Although laboratory
sediment testing may not remove all of the uncertainties regarding a
pesticide and its interactions in the environment, these test can help
to reduce this uncertainty.

	It is the Agency’s position that the requirement for whole sediment
toxicity testing is not levied exclusively to remove or reduce
uncertainty of potential risk in sediment versus water column matrices.
 The conduct of sediment toxicity tests considers multiple routes of
exposure. Even assuming good correlation between water column and
sediment toxicity vis-à-vis EqP considerations, the comparison is most
likely limited to exposure pathways associated with sediment pore water.
The Agency believes that additional pathways should be considered (e.g.
ingestion, dermal, etc.), as would be the case for spiked sediment
toxicity tests, which we believe provides a better overall assessment of
potential risk in the sediment compartment than a water column study
alone. The use of sediment toxicity studies is already limited primarily
because they are generally only considered after vigorous problem
formulation.

COMMENT   Two commenters (#120, #122) questioned the data requirement
for the whole sediment chronic invertebrate study as no guideline was
listed for this requirement.  They suggested that EPA harmonize with
OECD and cite OECD Method 218 for the chronic study.

RESPONSE   The Agency is harmonized with OECD with respect to this data
requirement.  OECD Guideline 218 (Sediment-Water Chironomid Toxicity
Test Using Spiked Sediments) was drafted to take into consideration
“all potential routes of exposure” and is focused on long-term
exposure (C. tentans 28 – 65 day exposure). This coincides with the
Agency’s needs and protocol for chronic sediment testing.

COMMENT   There were three comments (#120, #124, #133) that asked for
clarification of the Agency’s definitions of acute and chronic
sediment toxicity studies as described in the preamble.  One of the
comments stated that the acute sediment testing guidelines most commonly
used in the USA are more analogous to a chronic fish early life stage
study (ELS) in which mortality and growth are measured, than to acute
fish or Daphnia studies.  Another commenter thought that the typical
duration of greater than 10 days for most sediment toxicity studies was
more representative of chronic effects, not acute effects, as this time
period represents a significant portion of the typical test organism
life span.

RESPONSE   The Agency does not consider the ELS to be a chronic test
because reproduction is not a component of the testing.  Study duration
of 10 days covers early instar growth for chironomids.  The life cycle
of a chironomid is about 28 days (egg to egg).  The 10 day study is very
appropriate for acute toxicity evaluation, but not for a chronic
assessment.  The 10 day acute sediment testing covers morbidity and
growth, whereas the 48 hr EC50 invertebrate acute study only addresses
morbidity.  Neither study evaluates reproduction.  This is measured in
the chronic 65 day sediment study, as well as the invertebrate full life
cycle study.

	The chronic sediment study continues through emergence, which is a
measure of reproductive success.  The guideline, EPA/600/R-99-064,
provides the methodology for the 50 to 65 day Chironomus tentans
life-cycle sediment toxicity study.  The endpoints include 20 day larval
survival and weight, female and male emergence, number of egg cases
oviposited, number of eggs produced, and the number of hatched eggs.
The guideline also contains the 42 day Hyalella azteca which, likewise,
measures reproduction endpoints.  Guideline EPA 600/R-01-020 provides
the methodology for the 28 day marine/estuarine sediment toxicity test
with Leptocheirus plumulosus, another chronic test which contains
reproduction endpoints.  The OECD 218 guideline, mentioned above, is 20
to 28 days in duration for C. riparius and C. yoshimatsui and 28 to 65
days for C. tentans. The endpoints in this guideline include development
time, total number of fully emerged male and female midges, with
optional 10-day larval survival and growth.

COMMENT   Six commenters (# 113, #120, #122, #124, #125, #133) expressed
concern about the numerical values for the Kd and the half-life factors
for the acute and chronic sediment tests.  One comment asked for
justification to support the selection of the Kd value of 50 as the
criterion.  They also asked the Agency to clarify if the Kd value is the
mean, the maximum or 90%tile upper confidence limit of the mean value
observed in the soil adsorption studies.  This commenter proposed
alternative criteria for the acute study:  the study is required if the
soil Kd (specify mean, maximum or 90% tile) > 50, and; if the half-life
in soil or sediment is > 1 day (as indicated by aerobic soil, anaerobic
soil or aquatic metabolism sediment-phase degradation studies). These
criteria would lead to the following conclusions: the study is not
triggered if the material degrades rapidly in soil and sediment
(half-life < 1 day), or if the material is sorbed weakly to soil or
sediment (Kd < 50).

RESPONSE   The Kd criterion represents the mean value observed in the
soil adsorption studies.  The Agency’s justification in the proposed
rule for selecting Kd > 50 L/kg as a criterion for requiring the study
was that this value would capture those chemicals with about 80%
adsorption to sediments (relative to organic carbon).  In the 1980s the
Agency considered selecting a Kd value lower than 50 L/kg, in the range
of 3 to 10 L\/kg; however, at the time the proposed rule was drafted,
EPA believed a Kd > 50 was sufficiently conservative.

COMMENT   The Agency received a comment from Canada’s PMRA (#82) that
questioned the appropriateness of using the Kd value as a trigger for
sediment testing.  They stated that their experience indicated that
pesticides with relatively low Kd values (less than 50) may readily
partition to the sediment.  They suggested that the trigger should be
based on the results of the aquatic transformation studies, particularly
the mass balance results and the half lives in sediments.  They
discussed data that showed significant binding of the chemical, as
determined by unextractable residues, when the Kd value ranged from ∼2
to 14, much less than the value of 50 L/kg used by EPA.

RESPONSE   Based on the comment from PMRA, Agency scientists re-analyzed
the  value for the Kd criterion with data from the US Geological Survey
(USGS).  [U.S. Geological Survey.  2000.  Pesticides in Stream Sediment
and Aquatic Biota.  Current understanding of distribution and major
influences.  FS 092-00 (8-24-00).  4 pages.] [ url =

     HYPERLINK "http://ca.water.usgs.gov/pnsp/rep/fs09200/fs09200.pdf"
http://ca.water.usgs.gov/pnsp/rep/fs09200/fs09200.pdf  ).]  The Kd
values for pesticides commonly detected in sediment ranged from 1.6 to
2,095 with a mean value of 86 and a median value of 59.  This analysis
provided EPA with an important new perspective on Kd values, and the
Agency considered lowering the value of the criterion. However, EPA
decided not to change

the Kd value from that in the proposed rule based on science and policy
considerations. First, the Kd value, which indicates binding potential
of the pesticide (unadjusted for dependency upon organic carbon) is not
the primary factor in determining the need for sediment testing (i.e.

persistence, toxicity and exposure are the main factors). More
importantly, the Agency believes that such a change warrants input from
the scientific community along with broader public input on the Kd
trigger. The Agency may consider changing the Kd value in future updates
to part 158 requirements.

COMMENT   One commenter (#122) appeared to question which environmental
fate metabolism studies are used to determine the persistence criteria
that may trigger the acute sediment study.  They stated that the study
is required if the Kd > 50L/kg in either aerobic soil or aerobic aquatic
metabolism studies.  They wondered if the anaerobic soil half-life value
could also be used as an additional predictor of sediment persistence.

COMMENT   One commenter (#122) stated that it does not make much sense
to require the acute study if the half-life is moderately short (i.e.
<10 days), because acute toxicity would still be a concern if the
half-life were longer.  They wondered if this was a typo.  They
proposed, instead, that a very short soil or sediment half-life could be
a criterion for not requiring the study; e.g. if the half-life is <1
day, the study should not be required because residues would likely not
reach a water body in significant concentrations regardless of the
adsorption potential of the material.  Another commenter stated that
short half-life has less potential for invertebrate effects than a
chemical with a half-life greater than 10 days.

COMMENT   Five commenters (#120, #122, #124, #125, #137) stated that it
is difficult to assess EPA’s triggers for sediment toxicity testing
due to inconsistencies in the document.  The triggers to which they are
referring are reported in Unit X.B.2.i and ii (p. 12289d) and
§158.400(e), test notes 23 and 24 (p. 12345c) in the proposed rule.
The trigger for acute testing is reported to be a Kd  > 50 mg/L and a
half life of < 10 days. The commenters believe that using the symbol for
“less than” in reference to the half life value in the acute test is
a typographical error and should have read > 10 days.  For chronic
testing the trigger is a half-life > 10 days, along with Kd > 50 mg/L,
and a reference to the acute sediment studies (EEC > “acute”
sediment EC50/LC50 ), implying, in their view, that an acute study must
be done prior to conducting the chronic.  They requested that the Agency
clearly specify the conditions for both acute and chronic testing. They
stated that three factors, adsorption, persistence, and toxicity, are
important in determining whether a compound is of potential concern in
the sediment.  In their opinion, all three factors should be considered
when setting triggers for sediment toxicity testing.

RESPONSE   It appears from the above comments that the commenters
misunderstand the purpose of the triggers cited above.  The Agency
affirms that the intent of the triggers for the acute and chronic
sediment tests is not to determine length of test.  They were designed
to determine if the sediment compartment should be considered for
testing.  Once that determination is made, then problem formulation will
determine the specifics of the data required.  The Agency strongly
advises that the registrant consult with the biologists concerning type
of study and test organism selection.  The Kd trigger, which is the
partition coefficient used as an expression of binding capability of the
chemical, will be the same for either the acute or chronic sediment
test.  It is the persistence (i.e. half-life) that drives the decision
of which length of study to require.  For example, if the soil or
aquatic aerobic/anaerobic half-lives are less than 10 days (Agency
policy is to use the most conservative value, unless evidence is
provided to support the use of an alternative value), then the Agency
would accept the10 day sediment study, unless there are clear
reproductive issues a priori.  For half lives greater than 10 days, a 28
to 65 day study would be more appropriate.

	The Agency must determine if the proposed use pattern will result in
the compound reaching an aquatic system via drift and/or runoff at
levels that could result in risk to aquatic organisms. This potential
for exposure to an aquatic system is determined through appropriate
modeling or monitoring data. Once the Agency determines or extrapolates
that the use pattern has the likelihood for chemical exposure to an
aquatic system the triggers for persistence and adsorption are reviewed
(previously discussed). Toxicity will be taken into consideration
relative to potential exposure.  Consultation with the Agency is needed
if the registrant is uncertain as to which length of study is
appropriate.

COMMENT   Two commenters (#124, #137) proposed that a value of log Kow >
3 is a more commonly used value with which to judge whether a compound
might have adsorptive potential.

RESPONSE   The agency agrees that the Kow (octanol-water partition
coefficient), along with the Koc (soil organic carbon-water partition
coefficient), are valid environmental fate values to use as criteria for
these studies.  Both values are frequently more available than either
the Kd or half-life values.  The log Kow > 3, which is equivalent to Koc
> 1000) is a more conservative value.  Subsequently, a pesticide’s
requirement for submission of sediment studies can also be determined by
either of these two values.  The test notes in the final rule were
revised to include the Kow and Koc.

COMMENT   The Agency received five comments (#120, #122, #124, #125,
#137) regarding the statement in the Preamble which states that the
sediment testing requirement “would not be commonly required.”  They
contended that this statement is misleading because they view the
proposed trigger levels as quite liberal, such that a large number of
compounds, including those where no sediment concern has been
identified, would trigger testing.  According to them, the trigger Kd >
50 L/kg is quite low, and inconsistent with current scientific
knowledge.

RESPONSE   The Agency acknowledges that the statement would not be
commonly required” was misleading.  The Kd criterion represents the
mean value observed in the soil adsorption studies.  The Agency’s
justification in the proposed rule for selecting Kd > 50 L/kg as a
criterion for requiring the study was that this value would capture
those chemicals with about 80% adsorption to sediments (relative to
organic carbon).  In the 1980s the Agency considered selecting a Kd
value lower than 50 L/kg, in the range of 3 to 10 L\/kg; however, at the
time the proposed rule was drafted, EPA believed a Kd > 50 was
sufficiently conservative.  Based upon the analysis of the USGS data and
USGS report, the Agency is confident in the selection of a Kd value > 50
L/kg as one of the triggers for requiring sediment toxicity testing.

COMMENT   Commenter #122 questioned the use of an EEC (estimated
environmental concentration) to trigger the chronic toxicity study as
this value is prone to considerable variation and non-uniformity.  Each
EEC calculation is a function of a large number of assumptions in the
modeling including the very wide range of environmental characteristics
of the potential target sites.  For purposes of simplification and
uniformity, they proposed alternate criteria, based on persistence and
toxicity, without calculation of an EEC.   Their proposal is:  1) the
chronic study is required if the acute toxicity is <100 mg/kg sediment
(or some other suitable limit indicating a ‘practically non-toxic’
classification) or the soil Kd (specify mean, maximum or 90% tile) > 50,
and; 2) the sediment half-life is >X days in aerobic soil or aquatic
metabolism studies; otherwise, the chronic study is not required.  These
criteria trigger a chronic study if the material is persistent and sorbs
to soil/sediment, or is acutely toxic to sediment organisms and is
persistent.

RESPONSE   It appears that the question is really the appropriateness of
EEC versus toxicity for requiring a chronic sediment toxicity test.
 One advantage of using the EEC is the fact that its determination is
based on the modeling of variables unique to the respective chemical,
therefore any uncertainty would be due to the limitations of the model,
and certain spatially explicit deviations. The major weakness of using a
toxicity threshold as a trigger for this test is the fact that the data
base of laboratory sediment toxicity studies is not yet robust enough to
exact any meaningful correlations of intrinsic toxicity in the sediment
to a specific threshold of water column toxicity.  A level of 100 mg/kg
may be adequate for water column, but whether it is an appropriate
threshold for sediment still needs to be determined. Furthermore, in
these early stages of sediment toxicity testing and sediment risk
assessment, perhaps adsorption and persistence should be the key
criteria for triggering a sediment toxicity test.

COMMENT   One comment (#122) stated that the criterion for persistence
in soil/sediment should probably be less than 10 days. They continued
that a material with a 10 day half-life will degrade by a little less
than 75% in a 28-day midge life-cycle study, indicating that a
significant fraction of material could be present over the life-span of
a sediment-dwelling organism.  They proposed that a more suitable cutoff
would ensure degradation of material to an insignificant level well
before the life-span of an indicator organism elapsed.  For example, a 2
day half-life criterion would allow 14 half-lives to elapse in 28 days,
and would ensure the degradation of material to insignificant levels
(>99.9% degradation).

RESPONSE   The Agency reiterates that the use of a half-life value of
less than 10 days for the persistence trigger can be evaluated for a
future update of this rule, based on the sediment toxicity studies
submitted following publication of this rule.

COMMENT   This commenter (#122) stated that the half-life criterion
should be based on the degradation of the analytically-identifiable
parent material, and not on the dissipation of the non-extractable
residue which cannot be analytically identified as the parent material.
They continued in their statement that the non-extractable residue is,
by definition, not extractable, and therefore, also not biologically
available to sediment dwelling organisms.

RESPONSE   The Agency has not yet determined specifically which
half-life correlates best with greatest sediment adsorption and
exposure.  Therefore, we generally use the “worst-case” half-life of
the soil or aquatic aerobic or anaerobic half-life.  However, through
problem formulation and conceptual modeling, it would be determined a
priori whether residual pesticide concentrations are likely to occur in
water and sediment, and only in cases where exposure is likely would
testing be required.

COMMENT   The Agency received one comment (#56) that questioned why the
LC50/EC50 values are triggers for the chronic whole sediment toxicity
test.  They stated that chronic toxicity is often exhibited at
concentrations lower than the LC50/EC50 values.  They suggested that a
more appropriate trigger would be that sediment concentrations exceed
the NOAEC (no adverse effect concentration) or 0.1 * LC50/EC50 values.

RESPONSE   The Agency reiterates that the triggers are principally for
determining which chemicals warrant a sediment toxicity study at all.
However, the Agency agrees that the condition in test note 22 regarding
the LC50/EC50 values is unclear and revised the statement to read

	“The estimated environmental concentration in sediment is greater
than 0.1 of the acute LC50/EC50 values.”

	COMMENT   One commenter (#120) expressed concern that testing would be
required, regardless of the low risk for aquatic contamination, if the
triggers listed in these two test notes applied to the chemical under
review.  They asked the Agency to identify specific use patterns (seed
treatments and soil-incorporated pesticides, for example) that would not
require sediment testing based on low leaching potential and strong
adsorption properties.

	RESPONSE   The response to this comment lies in the Agency’s decision
that problem formulation will determine the specifics of the data
required.  The Agency assesses these chemical properties in conjunction
with available toxicity data in order to assess risk and whether
sediment testing is warranted.  With regard to the Agency predefining
use patterns that will not require sediment testing, this is not an easy
effort.  The argument that compounds with strong adsorption properties
and low leaching potential should not reach streams and lakes especially
if they are soil incorporated is a position that the Agency has usually
followed.  However, the Agency has recently been presented with
monitoring data showing that synthetic pyrethroids (family of compounds
that are highly adsorptive to organic matter) used in residential
settings (lawn care, building perimeter use, crack and crevice use,
etc.) can result in runoff to storm drains that empty into nearby
streams (Weston, D.P., J.C. You, M.J. Lydy.  2004.  Distribution and
toxicity of sediment -associated pesticides in agricultural-dominated
water bodies of California’s Central Valley.  Environmental Science
and Technology.  38:10:2752 - 2759).  For this reason, we cannot define
specific use patterns or applications that will not automatically
require sediment testing.

COMMENT   One commenter (#120) wanted EPA to specify in the test notes
when freshwater or marine organisms must be tested for sediment
toxicity.

RESPONSE   Nearly all chemical contaminants entering coastal waters are
likely to accumulate in estuarine or marine sediments.  Therefore,
sediment toxicity data are required for marine/estuarine test species if
the product is intended for direct application to the estuarine or
marine environments, or the product is expected to enter this
environment in concentrations which the Agency believes to be
significant, either by runoff or erosion, because of its expected use or
mobility pattern.  Refer to test note 23 in the final rule for the
specific wording.

COMMENT   The Agency received three comments (#113, #124, #137)
regarding the Agency’s requirement for using spiked sediment in the
studies as opposed to the EU’s requirement for using spiked water.
They believe that this difference results in less harmonization and
additional studies to address the same basic risk question.  They
proposed that the Agency should adopt the spiked water procedure
currently in use instead of imposing a new study design.

RESPONSE   The Agency requires spiked sediment testing to better
understand the potential effect of sediment bound pesticide to benthic
organisms. Test methods to address this information need are also
covered in the OECD Guidelines 218. The OECD Guideline 219 study relies
on spiked water as opposed to spiked sediment.  Although the Agency
usually accepts the 219 study as supplemental information, the study
does not address the Agency’s concerns regarding the prolonged
exposure of sediment bound pesticides to sediment-dwelling organisms.
The OECD Guideline 219 spiked water study does not include equilibration
of pesticide bound sediment with pore water, which can affect the
bioavailability of the compound in this compartment.

COMMENT    The Agency received one comment (#82) regarding an acute pore
water test as part of the sediment testing scheme.  The commenter
questioned the utility of an acute pore water test for regulatory
purposes because many benthic species aerate their immediate environment
by actively circulating overlying water through their burrows and thus
the toxic effect may be more closely associated with water column
concentrations than with pore water concentrations.  They recommended
that a whole sediment toxicity test is more appropriate because toxicity
will be captured from all routes of exposure.

RESPONSE   Whole sediment toxicity testing captures all routes of
exposure and consists of the sediment and associated pore water. The
Agency does not require separate pore water testing.  Pore water
toxicity is an important part of these tests as these data provide
additional information on toxic exposure to benthic organisms other than
through direct contact or ingestion of sediment particles.
Concentrations of chemicals in pore water can be calculated from the
corresponding sediment concentration if they are not measured directly.
The registrant must address pore water issues when they design the
study. [Guide for planning and conducting sediment pore water toxicity
identification evaluations (TIE) to determine causes of acute toxicity
at Navy aquatic sites.  Naval Facilities Engineering Service Center.
User’s Guide UG-2052-ENV.  Prepared by Science Applications
International Corporation.  Newport, Rhode Island 02840.  March 2003.
http://web.ead.anl.gov/ecorisk/methtool/pdf/ug-2052-tie.pdf]

2.  Fish Acute

COMMENT   The Agency received three comments, from #124, #125 and #133,
regarding the fish acute data requirement.  The comment asked for
clarification regarding the number of freshwater fish studies that are
now required.  According to their interpretation, the new rule seems to
suggest that a second fish species would be required to support
greenhouse and indoor uses. This is clearly supported in Table 3 of the
proposed rule, however EPA should review the text description for
clarity.  Currently, Part 158 requires two freshwater fish studies with
the TGAI to support terrestrial and aquatic (food crop and nonfood),
forestry, and domestic outdoor uses and conditionally requires one of
these studies for greenhouse (food crop and nonfood) and indoor uses.

RESPONSE   With regard to greenhouse use, the Agency requires the
testing of one fish species for labeling purposes.  If the LC50 < 1 ppm
no other fish species testing is required. However, if the LC50 is
between 1 and 100 ppm a second species will be required.  Although this
appears counterintuitive, the rationale reflects the need for labeling
for greenhouse use since the Agency does not conduct quantitative risk
assessments on this use.  If the LC50 is < 1 ppm, the label statement
(toxic to aquatic organisms, etc) is used.  If the LC50 is between 1 and
100 ppm a second fish acute test would be required to substantiate the
potential for hazard to aquatic organisms and to ensure the appropriate
labeling (e.g., if the second fish study produces an LC50 < 1 ppm).
SEQ CHAPTER \h \r 1 [Note– EPA guidance documents for the fish acute
toxicity study indicate that testing above 100 ppm would not be needed
as the toxicity category for test concentrations > 100 ppm is
“practically nontoxic”.   This ecotoxicological category of toxicity
is adapted from Insecticides, Brooks, H.L. et al. (1973) Cooperative
Extension, Kansas State University, Manhattan, Kansas.  Refer to
Pesticide Reregistration Rejection Rate Analysis: Ecological Effects.
EPA 738-R-94-035.  December 1994; and the Agency’s Technical Overview
of Ecological Risk Assessment

Analysis Phase: Ecological Effects Characterization.  (  HYPERLINK
"http://www.epa.gov/oppefed1/ecorisk_ders/toera_analysis_eco.htm"
http://www.epa.gov/oppefed1/ecorisk_ders/toera_analysis_eco.htm )  which
lists the Program’s ecotoxicity categories for terrestrial and aquatic
organisms.]

3.  Fish Chronic

COMMENT   The Agency received one comment (#124) regarding the
description of chronic testing with saltwater organisms.  In Section
X.3.vii of the draft preamble, the Agency discussed the needs for the
fish early life stage test and the invertebrate life cycle test for
freshwater species, but did not discuss these studies for saltwater
species.

RESPONSE   Although discussion of chronic tests with saltwater species
was missing from the preamble, the draft test notes in the proposed
regulatory text adequately indicated the conditions and use categories
for requiring these tests with saltwater species.

COMMENT   One commenter (#122) suggested that the Agency take into
consideration the difficulties of using EEC - based triggers for the
chronic studies.  They also stated that there is no justification to
limit chronic studies to those products with high acute toxicity.

RESPONSE   The Agency affirms that chronic studies are required to
support registration of an end-use pesticide product that is applied
directly to water or is expected to be transported to water from the
intended use site. These study requirements reflect the uncertainty that
surrounds pesticide exposure and their potential for impact to aquatic
organisms. Since exposure is a major driving parameter is assessing
acute and/or chronic risk, this factor must be defined and addressed.
However, when this information is lacking, the Agency generally
evaluates the need for chronic testing by assessing the likelihood of
risk occurring and if any of the following conditions apply: 1)
pesticide is persistent in the aquatic environment and is expected to be
present in water in a continuous or recurrent manner; 2) the chemical
accumulates; 3) EEC or actual water concentrations are < 0.01 of the
acute toxicity values; 4) pesticide mode of action or other studies show
that reproductive physiology may be affected from exposure.

COMMENT   The Agency received one comment (#122) that questioned why the
fish life cycle study can be required based on the relationship between
the EEC and the no-observed-effect level in the invertebrate life cycle
study.

RESPONSE   The Agency uses the data from the fish life-cycle study to
evaluate risk from chronic pesticide exposure to fish reproduction and
other life stages.  The Agency can use the results of reproduction
studies from any other organism, including invertebrates, if the data
suggest that the reproductive physiology of fish can also be impacted.

4.  Testing of Degradates

COMMENT   The Agency received a comment (#114) that the data
requirements should include toxicity testing with degradates of
pesticides as they can present significant environmental risks.

RESPONSE   The Agency evaluates degradates in relation to their
potential toxicity and does require appropriate testing on a
case-by-case basis if the degradate appears toxic.  If the environmental
fate data show the degradates can potentially persist, and Subpart F
toxicology data show they are toxic, then aquatic toxicity testing is
required.

5.  Sublethal Endpoints

COMMENT   One commenter (#127) stated that toxicity test results for
sub-lethal endpoints other than growth and reproduction are also
necessary.  For example, effects on behavior, swimming performance, and
reproduction can be critical to the survival of a species

RESPONSE   The Agency does summarize sublethal endpoints in the risk
assessment process when this information is available. Acute and chronic
study guidelines require that the study authors report sub-lethal
effects if there is an occurrence (swimming performance, lethargy, etc);
the extent to which behavioral or swimming performance data is used in a
quantitative fashion is limited by uncertainty in relating these
responses to quantitative responses in demographic rates (e.g.,
mortality, reproductive fitness) that underlie population responses.

6.  Bioaccumulation Testing

COMMENT   Three commenters (#120, #124, #137) stated that the test notes
for the bioaccumulation and bioavailability studies were unclear and did
not adequately describe the conditions under which the studies would be
required.

RESPONSE   The Agency also received several comments about these studies
under the environmental fate data requirements.  This suite of studies
was included in not only the aquatic organisms data requirements, but
also in the environmental fate data requirements.  Those who commented
about the studies in both tables stated that test note 10 in the draft
fate table was well-written and descriptive of the conditions for
requiring these studies.  They recommended that test note 10 should
replace the test note for these studies in the aquatic organisms table.
For the sake of clarity, the bioaccumulation/bioavailability data
requirement was deleted from the environmental fate data requirements
table in the final rule, Subpart N, and test note 10 from the draft fate
table (Not required when the octanol/water partition coefficients of the
pesticide and its major degradates are less than 1,000; or there are no
potential exposures to fish and other nontarget aquatic organisms; or
the hydrolytic half-life is less than 5days at pH 5, 7, and 9) is now
test note number 19 for these studies in the Subpart G in the final
rule.

7.  TEP testing

COMMENT   EPA proposed to require acute testing with the TEP for
freshwater and estuarine organisms based on either the introduction of
the TEP directly into an aquatic environment or the estimated
environmental concentration of pesticide equaled or exceeded one-half
the LC50 of the TGAI when the end product was used as directed or an
ingredient in the formulation was expected to enhance the toxicity of
the active ingredient or to directly cause toxicity to aquatic
organisms. One comment (#137) recommended that TEP testing with
estuarine organisms should be conditional based on the results of TEP
testing with freshwater organisms, or if estuarine organisms were more
sensitive to the TGAI than were freshwater organisms.

RESPONSE   The Agency requires TEP testing of freshwater and estuarine
organisms for all outdoor uses. As the environments of the estuarine and
freshwater organisms are different, how the chemical ingredients that
comprise a formulated product will react in the different aquatic
systems cannot be readily predicted. Therefore, the responses of each
group of organisms are independent of each other, necessitating testing
of both freshwater and estuarine organisms with the EP in addition to
the TGAI, if the triggers in the test note (9) are met.

Plants

1.  Nontarget Plant Guidelines and Harmonization

COMMENT  The Agency received six comments (#112, #122, #123, #124, #137,
#139) stating that the data requirements for nontarget plant testing
should not be promulgated if the test guidelines upon which the data
requirements rely are not finalized.

RESPONSE   While the final rule deals solely with data requirements for
conventional pesticides, the Agency recognizes the importance of the
connection between these final data requirements and the guidance
documents that provide information on how the data requirements may be
satisfied.  The Agency is in the process of updating its nontarget plant
test guidelines with the OPPTS and the OECD.  Guidelines are scheduled
to be completed and available to the public by late 2007.  Nonetheless,
guidelines are guidance documents only, and the promulgation of data
requirements does not depend on the availability of guidance documents.

COMMENT   Two additional comments (#122, #124) also encouraged the
Agency to harmonize the respective guidelines for these studies. Two
comments mentioned that OECD is currently considering draft guidelines
for seedling emergence and vegetative vigor studies.  They encouraged
the Agency to harmonize the respective guidelines for these studies.

RESPONSE   The comment in this section speaks more towards guidance that
is being proposed by OECD regarding individual non-target plant data
requirements and the specifics on how to conduct the individual studies.
 The Agency is a participating member of OECD and will harmonize with
these plant guidelines when they are completed.

2.  TGAI vs. TEP as the Test Material

COMMENT   Six commenters (#113, #122, #124, #125, #133, #137) expressed
concerns about the requirement that the TEP is the test material for the
terrestrial plant studies.  The stated preference was that use of the
TEP as the test material be changed from a requirement to a
recommendation, with the TEP considered the preferred or standard test
substance.  An alternative to the Agency’s proposal was that the test
substance may alternatively be applied as either a formulation other
than the TEP or as the Technical Grade Active Ingredient (TGAI) if there
are issues or difficulties related to the use of the TEP for these
studies.

COMMENT   The most common concern expressed by the commenters was the
issue that during the development of a new product containing a new
active ingredient (AI), the final formula for the end use product may
differ from what was used in the testing.  Furthermore, the company that
develops the active ingredient and conducts the Tier I seedling
emergence and vegetative vigor studies and the Tier I aquatic plant
growth studies does not necessarily formulate the end products for that
active.  The developer of the AI may not necessarily know what use
patterns and TEP(s) the formulators may produce.  One of the commenters
raised the issue that this will create data compensation issues if a
formulator develops uses unknown at the time the AI is being developed.
The formulator appears to be required to generate data with TEP.  They
also stated that it is unclear whether the Agency expects new data each
time the composition of an existing TEP is changed.  In many cases,
these changes would not be expected to significantly change the results
of the test.  The Agency should be cognizant of this and require testing
of a formulation representative of the TEP.

RESPONSE   The Agency recognizes that new AIs in the early stage of
development may not have the final formula(s) for end-use products with
the new AI. The Agency expects that the adjuvants that enable the new AI
to penetrate the plant cuticle or be translocated to a plant’s site of
action effectively, to be used at the maximum percentage as it is
anticipated when the AI is marketed.  The Agency may require additional
testing if the final formulation appreciably differs from that tested.
Data generated with TEP is usually done by the registrant, that is, the
company submitting the application for the registration of the proposed
use.  As new uses are proposed, the Agency makes a brief determination
if additional data are needed based on the use pattern, toxicity of the
chemical to the organisms and the persistence of the chemical to the
environment.  The Agency also wishes to point out that the regulations
specify that the aquatic plant (Tier I and II) be tested with either the
TGAI or the TEP.  The terrestrial plants (Tier I and II) must be tested
with the TEP.

COMMENT   Other comments (#113, #122, #124, #137) concerned the
possibility that the TEP may be composed of a mixture of two or more
active ingredients.  They expressed the concern that as adverse effects
on plants are based on exposure to a single AI, it would be necessary to
modify the TEP to include only a single AI, or use the TGAI rather than
the TEP in order to obtain data on a single AI.  In this case, for
products that are in development at the time plant testing is conducted,
it is possible that some minor refinement to the formulation may be made
between the time testing is initiated and the product formulation is
finalized.  In this case, the plant tests may have been conducted on a
formulation that is similar to the TEP, but is not an exact match to the
TEP that is commercialized. Under these circumstances, testing of a
formulation that is representative of the TEP rather than testing
required to be of the TEP may be more appropriate.

RESPONSE   The Agency’s response is that mixtures of active
ingredients, if required to be tested, will be with TEP.  As to whether
mixtures are tested, this will be determined on a case by case basis.
Rarely does the Agency require testing of mixtures.

3.  Expansion of Data Requirements

COMMENT  The Agency received one comment (#133) regarding the statement
in the draft Preamble that  "EPA is not proposing any major changes to
the plant protection data requirements from those currently listed in
Part 158."  The commenter believes that this statement appears to
overlook the fact that EPA has in fact expanded the data requirements to
include outdoor residential uses, which were never subject to these
requirements, and expands the product testing to include not only TGAIs
but TEPs as well.  According to the commenter, EPA does not provide any
explanation as to why this increase in the scope of the requirements to
include end-use products as well as TGAIs is necessary.  They suggest
that these requirements be removed.

RESPONSE   The Agency has been requesting non-target terrestrial plant
tests with TEP for a number of years.  Commenter # 124 understands that
the change is bringing 158 into agreement with current policies and
guidelines, and they acknowledge this in their statement “This
revision is in line with current OPPTS guidelines and current Agency
practices.”  Many of the herbicide active ingredients cannot
significantly harm plants unless there are adjuvants available to help
the chemical penetrate the plant defenses (i.e. surfactants, etc.).
Outdoor residential uses are now included among the sites requiring
plant testing because data indicate that herbicide uses on these sites
such as turf can harm nontarget plants through runoff.  Turf is
classified an outdoor residential terrestrial use, and therefore
requires nontarget plant testing.

4.  Nontarget Plant Testing for Indoor Uses

COMMENT   One commenter (#120) asked for an explanation as to why the
Agency included indoor uses among those requiring nontarget plant
testing.

RESPONSE   The Agency acknowledges that including indoor uses among
those requiring plant testing was an error.  The table in the final rule
is corrected.  Non-target plant testing is not required for indoor use.
Additionally, in response to this comment, testing for aquatic non-food
residential use is also eliminated.

5.  Species Testing

COMMENT   The Agency received three comments with differing opinions
regarding the numbers and types of plant species that Agency requires to
be tested.  One commenter (#124) recommended that testing of five
aquatic species should not be required for pesticides that are not
herbicides.  The need for testing of other species should be based on
the EC50 values of the two species tested and the EEC.

RESPONSE   The Agency found that a survey of the herbicides and
insecticides for which aquatic plant data were submitted under FIFRA
showed that the most sensitive aquatic species can be any one of the
five species tested for herbicides and insecticides.  The Agency,
therefore, requires five aquatic plant species for non-herbicidal
pesticides.

COMMENT   Two commenters (#82, #128) stated that EPA should increase
the range of species tested in nontarget plant protection studies.  The
proposed data requirements leave unchanged EPA’s current practice of
requiring terrestrial plant testing on only ten species.  All of these
species are annual agricultural or vegetable plant species.  These ten
species are considered by the Agency to be surrogates for the 16,000
native plant species in the U.S.  One of the commenters would like to
see a movement away from the typical 10 crop species and a movement
towards inclusion of non-crops to represent more ‘ecologically
relevant’ species.  For example, hardwood trees, native shrubs,
conifers, native grasses, and ferns are all completely ignored.  One
commenter indicated that there is a list of suitable non-crop species
for testing in Annex 3 of the newly revised OECD Guidelines 208
(Seedling Emergence and Seedling Growth) and 227 (Vegetative Vigour,
March 21, 2006).  They recommended that this list should be included in
the EPA Guidelines since the EPA supported the OECD recommendation for
inclusion of non-crop species.

RESPONSE   The Agency agrees that some of the uncertainty inherent in
the use of crop species would be alleviated by the use of non-crop
species in toxicity testing.  To that end, the OECD Annex 3 table of
acceptable non-crop species will be incorporated into the 850.4100 and
850.4150 testing guidelines for Seedling Emergence and Vegetative Vigor
studies, respectively, to be harmonized with NAFTA and OECD.

6.  Additional Endpoints

COMMENT   One commenter (#128) stated that EPA should increase the
duration of nontarget plant protection tests and include reproductive
endpoints (endpoints that measure yield of fruit and seed).  Low dose,
high potency herbicides such as acetolactate synthase inhibitors have
been the subject of research over the last two decades because they move
away from target sites in water, on soil particles, and as spray drift,
and have caused reproductive injury to plants at herbicide
concentrations so low that did not produce visible leaf injury.  This
kind of effect can have ecosystem-level effects, but is currently
ignored by plant protection data requirements, in which the maximum test
length is 28 days, too short to capture the reproductive phase of most
species.

RESPONSE   The Agency acknowledges that having these additional
endpoints would significantly enhance the risk assessment analysis for
nontarget plants.  However, methodologies to measure these endpoints are
still under development.   Laboratory protocols are currently under
development for plant reproductive testing using various species.
Following the development of plant reproductive effects testing
protocols, we will submit these protocols, and how they would be used in
risk characterization, to appropriate Agency, stakeholder and public
peer review. Then we will make efforts to incorporate these studies into
our risk assessment paradigm via appropriate processes.

7.  TIER III Guidelines

COMMENT   The Agency received three comments (#122, #124, #137)
regarding the Tier III (field testing) study guidelines and the process
of problem formulation and refinement of the ecological risk
assessments.  They recommended that the field studies be conducted
within the context of problem formulation to characterize risks to
plants under actual use conditions.  Therefore, they believe that the
Tier III study guidelines should be revised as needed, to ensure the
studies provide useful information to refine the risk assessment and to
provide guidance on practical, manageable approaches to conducting these
studies.

RESPONSE   The Agency states that the comments in this section speak
more towards guidance for how to address individual non-target plant
data requirements and provide information that meets the needs of the
regulatory bodies. The problem formulation, relevant endpoints, and
approaches to conducting these studies are covered in the 850.4300
testing guidance as well as specifics on how to conduct the individual
studies.   Tier III non-target plant toxicity studies are conditionally
required.  These studies are required on case-by-case basis following
discussions with the registrant of the chemical(s) of concern.

8.  Proposed Test Note 3

COMMENT   The Agency received one comment (#122) regarding the placement
of proposed test note 3 for the Tier I and Tier II seedling emergence
studies.  The data table indicates that seedling emergence studies are
generally not required for granular formulations.  They indicated that
this is an error since the exemption for testing granular formulations
was previously directed at vegetative vigor studies rather than seedling
emergence studies. Additionally, the preamble indicated that vegetative
vigor studies are not required for baits as well as granular
formulations.  The test note should be corrected.

RESPONSE   The Agency acknowledges that proposed test note 3 was
inaccurately placed next to the seedling emergence studies.  This has
been corrected, and this test note now refers to the Tier I and Tier II
vegetative vigor studies in the final rule.

9.  Test Notes 5 and 6: The Conditions for Moving from Tier I to Tier II
Studies

COMMENT   The Agency received one comment (122) asking for clarification
of test notes 5 and 6 which state that “if a terrestrial species
exhibits a 25 percent or greater detrimental effect” and “if an
aquatic species exhibits a 50 percent or greater detrimental effect”,
respectively.

RESPONSE   The Agency agrees that the wording of both test notes is
ambiguous.

The new wording for test note 5 is, “Required if a tested terrestrial
species exhibits a 25 percent or greater detrimental effect in the Tier
1 study.  When Tier II testing is required, the test species must be the
species that showed detrimental effects in the Tier I testing.”

The new wording for test note 6 is, “Required if a tested aquatic
species exhibits a 50 percent or greater detrimental effect in the Tier
1 study.  When Tier II testing is required, the test species must be the
species that showed detrimental effects in the Tier I testing.”

COMMENT   Another commenter (#82) referred to the findings of the FIFRA
Scientific Advisory Panel (SAP) in 2001 when it convened to discuss the
proposed NAFTA Non-Target Plant Toxicity Tests.  The SAP indicated that,
progression from Tier I to Tier II should be based on a statistically
significant effect >10% relative to the control for aquatic plants and
between 50% to 25% for terrestrial plants.  This commenter recommended
that, as a conservative approach, however, to use the 25% for
progression from Tier I to Tier II for terrestrial plant studies.

RESPONSE   For terrestrial plants, the Agency agrees in that the
progression from Tier I to Tier II testing will remain 25% inhibition or
greater.  However, effects seen at less than 25% may raise concerns for
federally listed endangered and threatened species, and additional
testing at Tier II may be needed to mitigate the presumption of risk to
listed species.

10.  Requirement for ILV Testing in the Field Studies

COMMENT Five commenters (# 113, #122, #124, #125, #133) stated that the
proposed rule would "require independent laboratory validation [ILV] of
the environmental chemistry methods used to generate data associated
with [Tier III] studies".  According to them, the ILV requirement is
currently limited to methods for quantifying residues in food, soil,
water and air.  The proposed revision does not state which additional
matrices are to be addressed nor how the ILV would be used. The
requirement for ILVs would add an additional burden to the registrants
if ILVs are required for the spray mixture or other matrices for which
there are no current ILV requirements. They recommend that the proposed
requirement be clarified to accept ILV conducted to meet similar
requirements under Subparts N or O for residue chemistry and
environmental fate.  In their opinion, the need for additional ILV of
methods for these Tier III studies should be rare.

RESPONSE   An independent laboratory validation verifies that the
analytical method, as written by the study director, can be performed by
a second laboratory and that laboratory can achieve similar performance
results.  This ensures that other stakeholders interested in monitoring
for the pesticide will have an acceptable method to do so.  Tier III
plant studies are usually very rare and are requested only when
significant concerns for non-target plant risk are expressed.

	GLP standards in 40 CFR part 160 do not require ILV.  Use of ILV is
specified in the Ecological Effects Test Guidelines, OPPTS 850.7100 Data
Reporting for Environmental Chemistry Methods (ECMs).  This is a
harmonized guideline which has been in effect since the mid-1990s, and,
as such, is a codification of current practice.  Guideline 850.7100
states that all methods, including ILV, should be conducted under GLP.

Discussion of Comments on Human Exposure Data Requirements (Subpart K)

	The current data requirements in part 158 do not contain studies to
determine applicator exposure from pesticide use.  Since EPA believes
these data are essential for fulfilling its mandate to protect human
health from pesticide risk, including aggregated and cumulative risks,
it proposed to make to make applicator exposure studies a standard part
of its regulatory requirements.  EPA proposed to codify applicator
exposure data requirements in a new subpart to cover agricultural
applicators, occupational applicators, and residential applicators.

Data Requirements for Applicator Exposure

COMMENT:	Commenter 82 compared the U.S. data requirements with those of
Canada and concluded that in general, the U.S. data requirements
outlined in the proposed rule are now more harmonized with the Canadian
data requirements.

RESPONSE:  The U.S. has added data requirements for applicator exposure
and more specific data requirements for post-application exposure,
particularly for residential sites and some occupational sites such as
greenhouses.  The conditions under which data are required are very
similar to Canadian conditions.  Comparisons of proposed U.S. and
Canadian data requirements are somewhat complicated; data requirements
are based on use site categories that are classified slightly
differently between the two countries and the types of studies required,
while being essentially the same, are named differently.  However, in
the final analysis the data requirements are now very similar.

COMMENT:  Commenter 120 believed the exposure criteria that would
trigger applicator exposure studies were “so broad as to be
meaningless.”  This commenter believed that it would be preferable
“to state that these data requirements always apply except where
pesticides are applied via a completely closed system with no potential
for exposure during mixing, loading, or application, if that is the
Agency’s intent.  Otherwise, the Agency should clearly define the
conditions under which these data requirements are applicable.”

RESPONSE:  The Agency considers various factors such as:  hazard
(toxicity) of the active ingredient; incident report; information on
types of exposure; levels of exposure, duration of exposure; and methods
of application in considering whether to require chemical-specific
exposure data.  In making a judgment, the Agency also considers the
availability of surrogate data.  The Agency data based on exposure
assessment of individuals performing mixing/loading activities using
closed systems indicate that the individuals are indeed exposed,
although at rates lower than rates using open systems.  For very toxic
chemicals, estimates of exposure using closed systems can still result
in exposures of concern.  Furthermore, there are many types of closed
systems for which the Agency does not have data.  Therefore, the Agency
will retain the approach discussed above and believes it is more
flexible than “broad.”

COMMENT:	Commenter 120 strongly recommended that EPA rely on
determinations and/or surrogate data estimates for exposure from other
agencies such as the Occupational Safety and Health Administration
(OSHA) and recommended “that the Agency accept OSHA workplace exposure
limits in lieu of a requirement to conduct a specific study” and
“strongly recommends the Agency use surrogate data where
appropriate.”

RESPONSE:   The Agency does consider OSHA standards.  It must be noted
though that OSHA standards are developed for industrial workplace
exposures, which are likely to be enclosed workplaces.  Conventional
agricultural pesticide chemicals that are applied outdoors can present a
very different use scenario.  OSHA standards may not be based on a
toxicity database as robust as that generated by registrants to support
their products.   The Agency will rely on the most dependable database.

	The Agency has a long history of relying on surrogate exposure data and
databases.  To estimate occupational and residential exposures, the
Agency uses databases containing large numbers of measured values of
dermal and inhalation exposure for pesticide workers.  Using these
measured data from one study/scenario as surrogate or generic data for
another study/scenario is appropriate since it is generally believed
that the physical parameters of the handling and application process
(e.g. the type of formulations, the method of application, and the type
of clothing), not the chemical properties of the pesticide, control the
amount of dermal and inhalation exposure.

	However, for certain types of pesticide formulations or use scenarios,
there is no exposure data, and therefore, it is not possible to perform
an occupational/residential risk assessment.  This is particularly one
of the types of situations in which the Agency would require
chemical-specific exposure data.

COMMENT:	Commenters 125 and 133 asked “What will the criteria actually
be for each of the noted categories? Will the Agency publish the
threshold adverse effect levels for each category? Would generic data be
acceptable to fill the data requirements?”

RESPONSE: The proposed criteria in the rule were the toxicity data
requirements to be considered rather than specific values.  EPA can be
more transparent about the basic risk assessment process but further
transparency is difficult when the detailed process for an individual
pesticide is contingent on the data from multiple studies in the
database.  When assessing exposure and risk, EPA considers the toxicity
data in its database together with the exposure data for the pesticide.
Depending on the nature of the pesticide being evaluated, any number of
toxic effects may be selected for the risk assessment.  These toxic
effects may be found from any of the following studies in the toxicity
database.

870.3100    90-day Oral -- rodent

870.3150    90-day Oral – non-rodent

870.3200    21/28-day dermal

870.3250    90-day dermal

870.3465    90-day inhalation -- rat

870.3700  Prenatal developmental toxicity – rat and rabbit preferred

870.3800    Reproduction and fertility effects

870.4100  Chronic oral toxicity -- rodent

870.4200  Carcinogenicity – rat and mouse preferred

870.6100  28-day delayed neurotoxicity -- hen

870.6200  90-day neurotoxicity -- rat

870.6300    Developmental neurotoxicity

870.7485    Metabolism and pharmacokinetics

870.7600    Dermal penetration

	EPA then identifies any adverse effects in the toxicity database that
are relevant to the type of exposure for the pesticide.  It is not
possible to predict beforehand which adverse effects will be relevant to
a type of exposure.  The exposure data may be surrogate data from an
exposure database or chemical-specific exposure data.  The relevant
adverse toxicity data and the exposure data are then considered together
in the risk assessment.

	The Agency has a long history of relying on surrogate exposure data and
databases. However, for certain types of pesticide formulations or use
scenarios, there is no exposure data, and therefore, it is not possible
to perform a risk assessment.  This is the type of situation when the
Agency would require chemical-specific exposure data.

Dermal exposure studies

COMMENT:	Commenters 108, 110, 124 and 134 said that the Agency proposes
to add data requirements for both outdoor and indoor dermal exposure
studies (Guidelines 875.1100 and 875.1200). Guidelines 875.1100 and
875.1200 were developed utilizing OPP guidelines 230 and 231 as source
material. However, few changes were made in updating from 230, 231 to
875.1100 and 875.1200. Because of this the methodology described in the
guidelines is not current and inconsistent with the methodology being
used in studies.

RESPONSE:  See response under Inhalation exposure studies.

Inhalation exposure studies

COMMENT:	Commenters 108, 110, 124, and 134 pointed out that Guidelines
875.1300 and 875.1400 were developed using OPP guidelines 230 and 232 as
source material but few changes were made in updating from 230 and 232.
Because of this the methodology described in the guidelines is not
current with the methodology used in studies.

RESPONSE:   EPA acknowledges that these four guidelines were finalized
in 1996 and that scientific knowledge has progressed in the
approximately 10 years.  The Agency has reviewed and accepted for use in
various risk assessments many studies that are categorized as
non-guideline.  As the commenters have stated above, other methodologies
are being used in studies that are being reviewed by the Agency.  The
Agency will consider these comments as its scientists work to
revise/update the guidelines.

Biological monitoring

COMMENT:	While Commenters 110 and 124 supported including biological
monitoring as a conditional data requirement, they wondered if the
Agency would be permitted to evaluate such studies because of the Boxer
amendment imposing a one-year moratorium on such evaluations.  They were
joined by Commenters 113, 133, and 134 in recommending revision of the
requirement to permit the use of rodent or primate pharmacokinetic data
with supporting rationale regarding the applicability of the use of data
from a non-human species.

RESPONSE:  EPA will comply with any statutory or regulatory requirements
concerning human research and will modify its data requirements if
necessary.  EPA promulgated a final human studies rule on April 7, 2006
(71 FR 6137, February 6, 2006) covering types of human research.  In
many, if not most or all cases, biomonitoring studies conducted on
pesticides will be subject to the new requirements of the final rule.
The Agency believes that the use of rodent or primate pharmacokinetic
data in conjunction with human biomonitoring studies would significantly
increase the uncertainties of the exposure data, and the resulting risk
assessment.

Data reporting and calculation information

COMMENT:	Commenters 108, 110, 124, and 134 addressed Guideline 875.1600
by indicating that there is no mention of Good Laboratory Practices
(GLP) report requirements or PR 86-5 report-writing guidelines.  They
wondered if the Pesticide Handlers Exposure Database (PHED) remain a
viable option for new surrogate data since the proposed rule mentions
submitting data in a format for submission into PHED.

RESPONSE:  Guideline 875.1600:  Application Exposure Monitoring Data
Reporting specifies the data needed by Agency scientists for an
appropriate level of review and evaluation, and offers a format that the
Agency has found useful.  The guideline was written by science reviewers
for the scientists actually generating the data in a performing
laboratory.  The studies are eventually sent to the Agency, not by the
performing laboratory, but by the “person” who paid for the study.
The GLP statement and the other PRN 86-5 specifications are
administrative elements for inputting the study into the Agency’s
Master Record Identification (MRID) system.  Such formatting is
considered to be the responsibility of the submitter, not the performing
laboratory.

	The guideline currently contains a statement about submitting a
diskette for entry into PHED and reflects the electronic format
available when the guideline was finalized in 1966.  The next revision
of PR 86-5 will reflect the preferred format(s).  The Agency does not
plan to add new surrogate data into PHED but will continue to consider
the data already in PHED.  The fate of PHED and the generation of new
data are dependent on Agency efforts to take AHETF study designs to the
Human Subjects Review Board (HSRB).  The Agency approach for evaluating
data in PHED was the subject of a recent FIFRA Scientific Advisory Panel
(SAP) in January 9-12, 2007.   The Agency’s analysis will continue
throughout this year.

Product use information

COMMENT:	Commenters 108, 110, 124, and 134 were concerned that Guideline
875.1700 does not appear in the official final form of the OPPTS
Harmonized Test Guidelines for Occupational and Residential exposure.
They questioned the imposition or codification of a “data requirement
that relies upon or references a guideline that does not officially
exist” and recommends the Agency finalize and issue revisions to the
875 series of guidelines before imposing data requirements.

RESPONSE:  The Agency agrees that not all of the 875 Guideline Series
for Occupational and Residential Exposure have been finalized.  However,
the language for 875.1700 will be similar to 875.2700. The latter
guideline is one of the draft Guidelines that were presented to the
FIFRA Science Advisory Panel (SAP) in March 1998 appear on the
Agency’s website at   HYPERLINK
"http://www.epa.gov/scipoly/sap/meetings/1998/march/contents.htm"
http://www.epa.gov/scipoly/sap/meetings/1998/march/contents.htm .  The
Agency will be able to devote resources to finalization of the test
guidelines after meeting some more pressing deadlines and believes the
test guidelines will be finalized at the end of 2008.  In addition, the
Agency’s scientists can provide guidance to registrants or task forces
on aspects of study design and are always willing to work with
individual registrants to develop study designs for fulfilling data
requirements.

COMMENT:	Commenter 133 asked if product use information is simply the
label.  This commenter also wondered if recently submitted general task
force data provide such information.

RESPONSE:  Often the label is not descriptive enough of the exposure
scenarios, in particular, timing of applications and frequency of use.
Data such as those data that are available in the Residential Exposure
Joint Venture (REJV) survey can be acceptable.  The Agency will consider
these comments as its scientists work to finalize the guidelines at the
end of 2008.

Use of surrogate data

COMMENT:	Commenters 125 and 133 noted the discussion of the PHED
database, the mention of the Outdoor Residential Exposure Task Force
(ORETF) but no mention of Residential Exposure Joint Venture (REJV).
They said the Agency should not be singling one particular task force
for mention but should discuss all of the task forces that have
developed data.

RESPONSE:	 The commenters are correct in that the proposed rule on page
12309 state “[s]urrogate data may be obtained from several reliable
sources,” and then only discussed the use of PHED and ORETF surrogate
data.  Some of the other task forces that have generated exposure data
are the Indoor Residential Exposure Joint Task Force, the Agricultural
Handlers Exposure Task Force, and the Agricultural Reentry Task Force.

Data Requirements for Post-Application Exposure

	The re-entry protection data requirements in the current CFR are being
revised because they no longer meet the needs of the Agency in all
post-application settings.  The 1984 data requirements were developed to
assess the risks to agricultural workers and others who must enter a
treated field.  EPA has been concerned about exposure to pesticides in
occupational and residential settings and the proposed codification of
data requirements reflects this concern.  The proposed data requirements
would allow EPA to assess aggregated and cumulative risks with special
emphasis on children.

COMMENT:  Commenter 128 believes that for some pesticides, inhalation
exposures may comprise a substantial fraction of the total exposure that
EPA currently does not evaluate for non-fumigant pesticides.  This
commenter urged EPA to use the existing information collected by the
California Air Resources Board (CARB) and referenced several articles in
open literature.  Commenter 128 also supported changing the data
requirement for inhalation exposure (875.2500) from conditionally
required to required and recommended that vapor pressure and half-life
be used as a guide to potentially problematic chemicals early in the
risk assessment process.

RESPONSE:  The commenter supports the Agency’s proposal to require
post-application exposure data, in particular, for the inhalation route.
 As part of their comment, they cited data available from CARB
indicating off-site migration of volatile pesticides from agricultural
sprays having vapor pressures of greater than 1 x 10-6.   The Agency
acknowledges that there is a potential for exposure from this pathway
and will consider such factors such as vapor pressure and the half-life
of semi-volatile compounds when identifying chemical-specific data
requirements.

COMMENT:	Commenter 133 was concerned that the preamble indicated that
post-application exposures have been associated with a significant
proportion of reported incidents in the record and felt such conclusions
were inappropriate in the absence of any substantiation.  This commenter
stated that in many cases incidents reported to PCCs (poison control
centers) cannot be conclusively linked to pesticide use.

RESPONSE:  The Agency relies on a number of sources for incident data,
including poison control centers.  The reliability of the information is
evaluated on a chemical-by-chemical basis.

COMMENT:	Commenter 133 requested a better definition as to when soil
dissipation would be required for residential settings.

 RESPONSE:   Soil residue dissipation (Guideline No. 875.2200) is CR for
residential use patterns.  Test Note 7 for this data requirement states
that data are required for residential sites if the pesticide is applied
to or around soil or other planting media both outdoors and indoors,
e.g., residential greenhouse or houseplant uses.

COMMENT:	Commenter 133 believed that requiring Dermal exposure and
Inhalation exposure studies (guidelines 133-3 and 133-4) for residential
use will create problems for formulators and wondered whether modeling
or other generic task force data would be acceptable.

RESPONSE:  The commenter had not indicated the types of problems that
could be created as a result of requiring these data in residential use
patterns.  In the absence of the specific problems, the Agency can only
state that modeling or other generic data may be acceptable.  Applicants
are encouraged to discuss their considerations in those areas with the
Agency.

COMMENT:	Commenter 133 believed that the post-application exposure
requirements were newly imposed, contrary to the discussion in the
preamble, and that a great deal more data is actually being proposed for
collection than is necessary or reasonable.

RESPONSE:  Post-application exposure data have been required for
agricultural uses since a DCI was issued in 1995.  Since FQPA in 1996,
the Agency has routinely conducted residential exposure assessments for
all active ingredients that have use patterns indicating the potential
for residential exposures if the screening-level risk assessments
identify risks of concern.   For residential exposure assessments, the
Agency’s Standard Operating Procedures (SOPs) for Residential
Exposures can be used by Agency assessors.

Criteria for testing

COMMENT:	Commenter 133 pointed out that the two criteria for requiring
post-application exposure data were retrospective, not prospective.  The
commenter wondered how an applicant would know how to apply the criteria
if the active ingredient is new and no incident data or use history was
available.

RESPONSE:  	The Agency does not expect incident data for new products
with new active ingredients.

Biological monitoring

COMMENT:	Commenters 125 and 133 wondered what alternative studies were
possible if Congress banned human testing.

RESPONSE:    EPA will comply with any statutory or regulatory
requirements concerning human research and will modify its data
requirements if necessary.  EPA promulgated a final human studies rule
on April 7, 2006 (71 FR 6137, February 6, 2006) covering types of human
research.  In many, if not most or all cases, biomonitoring studies
conducted on pesticides will be subject to the new requirements of the
final rule.

COMMENT:	Commenter 133 asked for options when the Agency requires a
biological monitoring study where swimmers are exposed and passive
dosimetry methods are not feasible.

 RESPONSE:  When swimmers are exposed and passive dosimetry methods are
not feasible, the Agency relies on a swim model that that can also be
used in place of biological monitoring.

COMMENT:	Commenters 125 and 133 indicated that the biological monitoring
data requirement (875.2600) will place additional testing requirements
on formulators unless other generic task force data are acceptable.

RESPONSE:  The Agency believes that the development of generic task
force data could be possible for almost all active ingredients.
However, for certain pesticide formulations or use scenarios, there is
no exposure data.  In this type of situation, the Agency would require
chemical-specific exposure data.

COMMENT:	Commenters 109, 110, 122, 124 and 134 supported using human
studies conducted under proper ethical guidelines, but were concerned
whether the Agency would be permitted to evaluate such studies because
of the Boxer amendment to the FY2006 appropriations.  These commenters
recommended that the Agency provide flexibility in the development of
the supporting pharmacokinetic data; the commenters also recommended
revising the data requirement to permit use of rodent or primate
pharmacokinetic data with supporting rationale for using data from a
non-human species.

RESPONSE:   EPA will comply with any statutory or regulatory
requirements concerning human research and will modify its data
requirements if necessary.  EPA promulgated a final human studies rule
on April 7, 2006 (71 FR 6137, February 6, 2006) covering types of human
research.  In many, if not most or all cases, biomonitoring studies
conducted on pesticides will be subject to the new requirements of the
final rule.  The Agency believes that the use of rodent or primate
pharmacokinetic data in conjunction with human biomonitoring studies
would significantly increase the uncertainties of the exposure data, and
the resulting risk assessment.

Product use information

COMMENT:	Commenter 133 suggested that product use information should be
covered by recently submitted generic task force data while Commenter
125 suggested that such information should be covered by the Non-Dietary
Exposure Task Force (NDETF) and Residential Exposure Joint Venture
(REJV) data.

RESPONSE:   The Agency agrees that recently submitted generic task force
data should cover most currently registered products.  However,
additional chemical-specific data for other products (different active
ingredients) not covered by NDETF may be required in the future.

Description of human activity

 COMMENT:	Commenters 109, 110, 122, 124 and 134 agreed with the Agency
that information describing the possible activities in which people may
be engaged after a site has been treated (Guideline 875.2800) is
essential for accurate assessment of post-application exposure. The same
commenters believe that there are several aspects of the proposed
requirement that are problematic. They believe that these needs may be
adequately fulfilled through the Agricultural Reentry Task Force (ARTF)
Survey.  The commenters go on to state that ARTF has generated and
submitted by far the most extensive and comprehensive survey of North
American agricultural post-application  exposure activities that has
been performed to date, or is likely to be performed for some time to
come, and should be cited as a comprehensive source of information
available to satisfy this data requirement.

	Commenters 125 and 133 were pleased that human activity information
will become required information, including differences between adults
and children since these data have been generated by Outdoor Residential
Exposure Task Force (ORETF) and other task forces.

RESPONSE:   The Agency agrees that recently submitted generic task force
data should cover most currently registered pesticides.  However,
additional chemical-specific data for other products (different active
ingredients) not covered by task force data may be required, such as the
timing and frequency of use.

Data reporting and calculation information

	There were no comments regarding data reporting and calculation
information.

Nondietary ingestion exposure

COMMENT:	Commenter 133 believed the conditionally-required study to
evaluate potential oral exposure and the mention of “residue in the
rinsate from hand-washing” appears to imply intentional human dosing
and asked for an alternative if Congress bans human dosing.

RESPONSE:  First, Congress has not banned human dosing.  Consistent with
the Congressional direction to EPA in its 2006 Appropriations Act, on
February 6, 2006 EPA issued a final rule extending Common Rule
protections to non-pregnant, non-nursing adult human subjects of third
party research involving intentional exposure to pesticides (71 FR
6137).  The rule also forbids any new EPA or third-party research
involving intentional exposure of children or pregnant or nursing women,
and forbids EPA to consider in actions it takes under the pesticide laws
any research involving intentional exposure of children or pregnant or
nursing women, except under very narrowly defined circumstances when to
consider it would be more protective of public health than not to
consider it.

	The Agency's concern for potential non-dietary oral exposure of
children can be addressed in a way that is entirely consistent with
these new rules.  Several types of studies have been conducted in the
past and could be conducted in future under the new rules to explore
surface-to-hand transfers of residues from, e.g., lawns, other
plantings, decks, play structures, fabrics, indoor hard surfaces, etc.
These studies use adult volunteers to determine how much residue per
unit area transfers to a hand in contact with a pesticide-treated
surface.  One method for measuring this transferred residue is by
washing and rinsing the hand and capturing the rinsate for analysis.

	Results from this kind of study about how much residue transfers to an
intentionally exposed adult's hand can then be combined with data about
hand-to-mouth behavior of young children (from strictly observational
research) to estimate non-dietary oral exposures of children.  With
these estimates and other knowledge about the hazard of a pesticide the
Agency can assess the safety of the likely exposures of young children
without exposing them directly to the pesticide in question.

COMMENT:	Commenter 133 believes the Nondietary ingestion exposure data
requirement (Guideline 875.3000) should be addressed by generic task
force data bases.

RESPONSE:   The Agency believes that the development of generic task
force data could be possible for almost all active ingredients.
However, for certain pesticide formulations or use scenarios, there is
no exposure data.  In this type of situation, the Agency would require
chemical-specific exposure data.

Dislodgeable foliar residue dissipation and turf transferable residues

 COMMENT:	Commenters 109, 110, 122, 124 and 134 thought the application
of default factors for estimating these residues in current assessment
was sensible and encouraged the Agency to maintain the current default
policy to encourage sensible allocation of resources and include the
policy in the data requirement.  If the policy is maintained, the
commenters wondered whether is should be R as proposed.  As a member of
ORETF, Commenter 125 was pleased to see this data requirement proposed
as R.

RESPONSE:  The Agency encourages registrants to conduct
chemical-specific turf residue studies and concurrent dermal exposure
measurements.   The use of screening-level exposure assessments that
include the use of default factors remains an option for fulfilling this
data requirement provided that the screening-level risk is less than the
Agency’s level of concern.

The Agency believes that the requirement should remain required rather
than conditionally required because it believes the data collected is
important in assessing this important exposure pathway.

COMMENT:	Commenters 125 and 133 wondered what alternatives are proposed
if Congress bans human dosing experiments since these residues are
typically measured by hand presses and do involve human exposures.

RESPONSE:  EPA will comply with any statutory or regulatory requirements
concerning human research and will modify its data requirements if
necessary.  EPA promulgated a final human studies rule on April 7, 2006
(71 FR 6137, February 6, 2006) covering types of human research.  In
many, if not most or all cases, biomonitoring studies conducted on
pesticides will be subject to the new requirements of the final rule.

Soil residue dissipation

COMMENT:	For this requirement, occupational is R, but residential is CR.
 Commenter 133 wondered what residential scenarios would trigger this
requirement.

RESPONSE:  The commenter should refer to Test Note 7, which is linked to
that data requirement, which states:  “Data are required for
residential sites if the pesticide is applied to or around soil or other
planting media both outdoors and indoors, e.g., residential greenhouse
or houseplant uses.”

COMMENT:	Commenters 109, 122, 124, and 134 requested clarification of a
trigger for this data requirement since there is available data on
chemical release from soil in other parts of the data package (i.e.,
potential exposure to treated soil does not directly relate to exposure
to the pesticide).  This commenter points out that uses exist in which
most of the material applied ends up in the soil, but for the vast
majority of agricultural and residential use scenarios, there is
currently no reason to believe that post-application contact with
treated soil is more than a negligible contributor to exposure.

RESPONSE:  The Agency proposed to expand the Soil Residue Dissipation
study to include broader agricultural, greenhouse, nursery, forest, and
residential settings.  This study will be required for occupational use
sites involving substantial exposure to treated soil and conditionally
required for residential use sites when there is information suggesting
that the pesticide is persistent.

Dermal and inhalation exposure

COMMENT:	Commenters 109, 110, 122,  124 and 134 indicated that both ARTF
and ORETF have supplied comprehensive post-application exposure
databases to the Agency; ARTF and ORETF were primary suppliers of dermal
and inhalation exposure data for agricultural chemicals and lawns in