OFFICE OF

PREVENTION, PESTICIDES

AND TOXIC SUBSTANCES

June 28, 2006

MEMORANDUM

SUBJECT:	ROTENONE: Final HED Chapter of the Reregistration Eligibility
Decision Document (RED).  PC Code: 071003.  DP Barcode: D328478

FROM:	Charles Smith, Risk Assessor/Environmental Scientist

Elissa Reaves, Ph.D., Risk Assessor/Toxicologist

		Reregistration Branch 2

		Health Effects Division (7509C)

			AND

		Sherrie Kinard/Toiya Goodlow

		Yvonne Barnes

		Monica Hawkins

		Health Effects Division (7509C)

			AND

		R. David Jones, Ph.D.

		Environmental Fate and Effects Division (7507C)

THRU:	Alan Nielsen, Branch Senior Scientist

		William J. Hazel, Ph.D., Branch Chief

Reregistration Branch 2

Health Effects Division (7509C)

TO:		Katie Hall, Chemical Review Manager

		Reregistration Branch 2

		Special Review and Reregistration Division (7508C)

The attached Human Health Risk Assessment for the rotenone RED document
was generated as part of Phase 4 of the public participation process.
The Health Effects Division’s (HED) Final chapter reflects the
comments received during the Phase 3 public comment period.  In separate
memos the rotenone technical registrants (Prentiss, Inc. 3/7/06; Foreign
Domestic Chemicals Corporation 3/17/06; and Tifa Limited 4/5/06)
voluntarily cancelled all residential and food crop uses of rotenone
leaving only the piscicidal use pattern.  In this document, EPA presents
the results of its review of the potential human health effects
resulting from the use of rotenone as a piscicide.  The cancelled uses
of rotenone were previously assessed in the January 24, 2006 risk
assessment (DP barcode D307385), which can be found on EPA’s website.
This chapter includes a summary of the product chemistry review from
Yvonne Barnes, plant and ruminant metabolism review from Sherrie Kinard,
dietary risk assessment from Toiya Goodlow, toxicology review from
Elissa Reaves, occupational exposure and risk assessment from Charles
Smith, incidence review from Monica Hawkins, environmental fate and
drinking water exposures from R. David Jones [Environmental Fate and
Effects Division (EFED)], as well as risk assessment and
characterization from Elissa Reaves, and Charles Smith.

This risk assessment relies in part on data from studies in which adult
human subjects were intentionally exposed to a pesticide.  These
studies, listed below, have been determined to require a review of their
ethical conduct.  The listed studies have either received the
appropriate review or are in the process of being ethically reviewed.

	Clark NWE, Scott RC, Blain PG, Williams FM (1993).  Fate of
fluazifop-butyl in rat and 	human 	skin in vitro.  Arch Toxicol.
67:44-48.

	The PHED Task Force, 1995.  The Pesticide Handler Exposure Database
(PHED), Version 1.1.  Task Force members Health Canada, U.S.
Environmental Protection Agency, and the National Agricultural Chemicals
Association, released February 1995.

cc:	Tina Levine

	Jack Housenger

	Debbie Edwards

	William Hazel

	Margaret Rice

Table of Contents  TOC \o "1-4" \h \z \u

  HYPERLINK \l "_Toc139253797"  Table of Contents	  PAGEREF
_Toc139253797 \h  3

  HYPERLINK \l "_Toc139253798"  1.0 Executive Summary	  PAGEREF
_Toc139253798 \h  5

  HYPERLINK \l "_Toc139253799"  2.0 Ingredient Profile	  PAGEREF
_Toc139253799 \h  9

  HYPERLINK \l "_Toc139253800"  2.1 Summary of Registered/Proposed Uses
 PAGEREF _Toc139253800 \h  9

  HYPERLINK \l "_Toc139253801"  2.1.1 Registered Use Categories and
Sites	  PAGEREF _Toc139253801 \h  9

  HYPERLINK \l "_Toc139253802"  2.1.2 Application Methods and Rates
PAGEREF _Toc139253802 \h  9

  HYPERLINK \l "_Toc139253803"  2.2 Structure and Nomenclature	  PAGEREF
_Toc139253803 \h  11

  HYPERLINK \l "_Toc139253804"  2.3 Physical and Chemical Properties
PAGEREF _Toc139253804 \h  12

  HYPERLINK \l "_Toc139253805"  3.0 Metabolism Assessment	  PAGEREF
_Toc139253805 \h  13

  HYPERLINK \l "_Toc139253806"  3.1 Comparative Metabolic Profile
PAGEREF _Toc139253806 \h  13

  HYPERLINK \l "_Toc139253807"  3.2 Nature of the Residue in Foods
PAGEREF _Toc139253807 \h  13

  HYPERLINK \l "_Toc139253808"  3.3 Rat Metabolism	  PAGEREF
_Toc139253808 \h  13

  HYPERLINK \l "_Toc139253809"  3.4 Environmental Degradation	  PAGEREF
_Toc139253809 \h  14

  HYPERLINK \l "_Toc139253810"  4.0 Hazard Characterization/Assessment
PAGEREF _Toc139253810 \h  15

  HYPERLINK \l "_Toc139253811"  4.1 Hazard Characterization	  PAGEREF
_Toc139253811 \h  15

  HYPERLINK \l "_Toc139253812"  4.1.1 Database Summary	  PAGEREF
_Toc139253812 \h  15

  HYPERLINK \l "_Toc139253813"  <IP_ADDRESS> Critical Studies (animal, human,
general literature)	  PAGEREF _Toc139253813 \h  15

  HYPERLINK \l "_Toc139253814"  <IP_ADDRESS> Metabolism, toxicokinetics, mode
of action data	  PAGEREF _Toc139253814 \h  15

  HYPERLINK \l "_Toc139253815"  <IP_ADDRESS> Sufficiency of studies/data
PAGEREF _Toc139253815 \h  16

  HYPERLINK \l "_Toc139253816"  4.1.2 Toxicological Effects	  PAGEREF
_Toc139253816 \h  16

  HYPERLINK \l "_Toc139253817"  4.1.3 Dose-response	  PAGEREF
_Toc139253817 \h  18

  HYPERLINK \l "_Toc139253818"  4.2 Hazard Considerations	  PAGEREF
_Toc139253818 \h  22

  HYPERLINK \l "_Toc139253819"  4.2.1 Adequacy of the Toxicity Data Base
  PAGEREF _Toc139253819 \h  22

  HYPERLINK \l "_Toc139253820"  4.2.2 Evidence of Neurotoxicity
PAGEREF _Toc139253820 \h  22

  HYPERLINK \l "_Toc139253821"  4.2.3 Developmental Toxicity Studies
PAGEREF _Toc139253821 \h  23

  HYPERLINK \l "_Toc139253822"  <IP_ADDRESS> Developmental Toxicity Study
Conclusions	  PAGEREF _Toc139253822 \h  23

  HYPERLINK \l "_Toc139253823"  <IP_ADDRESS> Rotenone - COBS® CD® Rats
PAGEREF _Toc139253823 \h  23

  HYPERLINK \l "_Toc139253824"  <IP_ADDRESS> Rotenone - CD-1 Mice	  PAGEREF
_Toc139253824 \h  24

  HYPERLINK \l "_Toc139253825"  4.2.4 Reproductive Toxicity Study
PAGEREF _Toc139253825 \h  25

  HYPERLINK \l "_Toc139253826"  4.2.5 Additional Information from
Literature Sources	  PAGEREF _Toc139253826 \h  26

  HYPERLINK \l "_Toc139253827"  4.2.6 Pre-and/or Postnatal Toxicity
PAGEREF _Toc139253827 \h  26

  HYPERLINK \l "_Toc139253828"  <IP_ADDRESS> Determination of Susceptibility
 PAGEREF _Toc139253828 \h  26

  HYPERLINK \l "_Toc139253829"  <IP_ADDRESS> Degree of Concern Analysis and
Residual Uncertainties for Pre- and/or Post-natal Susceptibility
PAGEREF _Toc139253829 \h  27

  HYPERLINK \l "_Toc139253830"  4.3 Recommendation for a Developmental
Neurotoxicity (DNT) Study	  PAGEREF _Toc139253830 \h  27

  HYPERLINK \l "_Toc139253831"  4.3.1 Evidence that supports requiring a
DNT study	  PAGEREF _Toc139253831 \h  27

  HYPERLINK \l "_Toc139253832"  4.3.2 Evidence that supports not
requiring a DNT study	  PAGEREF _Toc139253832 \h  27

  HYPERLINK \l "_Toc139253833"  4.3.3 Rationale for a Database
Uncertainty Factor (UFdb)	  PAGEREF _Toc139253833 \h  27

  HYPERLINK \l "_Toc139253834"  4.4 Hazard Identification and Toxicity
Endpoint Selection	  PAGEREF _Toc139253834 \h  28

  HYPERLINK \l "_Toc139253835"  4.4.1 Acute Reference Dose (aRfD) -
Females 13-49 years old	  PAGEREF _Toc139253835 \h  28

  HYPERLINK \l "_Toc139253836"  4.4.2 Acute Reference Dose (aRfD) -
General Population	  PAGEREF _Toc139253836 \h  29

  HYPERLINK \l "_Toc139253837"  4.4.3 Chronic Reference Dose (cRfD)
PAGEREF _Toc139253837 \h  29

  HYPERLINK \l "_Toc139253838"  4.4.4 Incidental Oral Exposure (Short-
and Intermediate-term)	  PAGEREF _Toc139253838 \h  30

  HYPERLINK \l "_Toc139253839"  4.4.5 Dermal Absorption	  PAGEREF
_Toc139253839 \h  31

  HYPERLINK \l "_Toc139253840"  4.4.6 Dermal Exposure (Short-,
Intermediate- and Long- term)	  PAGEREF _Toc139253840 \h  32

  HYPERLINK \l "_Toc139253841"  4.4.7 Inhalation Exposure (Short-,
Intermediate- and Long-term)	  PAGEREF _Toc139253841 \h  32

  HYPERLINK \l "_Toc139253842"  4.4.8 HED’s Level of Concern (LOC)
PAGEREF _Toc139253842 \h  32

  HYPERLINK \l "_Toc139253843"  4.4.9 Recommendation for Aggregate
Exposure Risk Assessments	  PAGEREF _Toc139253843 \h  33

  HYPERLINK \l "_Toc139253844"  4.4.10 Classification of Carcinogenic
Potential	  PAGEREF _Toc139253844 \h  33

  HYPERLINK \l "_Toc139253845"  <IP_ADDRESS> Carcinogenic Potential in Rats
 PAGEREF _Toc139253845 \h  34

  HYPERLINK \l "_Toc139253846"  <IP_ADDRESS> Carcinogenic Potential in Mice
 PAGEREF _Toc139253846 \h  35

  HYPERLINK \l "_Toc139253847"  <IP_ADDRESS> Classification of Carcinogenic
Potential	  PAGEREF _Toc139253847 \h  36

  HYPERLINK \l "_Toc139253848"  4.5 Endocrine Disruption	  PAGEREF
_Toc139253848 \h  38

  HYPERLINK \l "_Toc139253849"  5.0 Public Health Data	  PAGEREF
_Toc139253849 \h  38

  HYPERLINK \l "_Toc139253850"  5.1 Incident Reports	  PAGEREF
_Toc139253850 \h  38

  HYPERLINK \l "_Toc139253851"  5.2 Other	  PAGEREF _Toc139253851 \h  39

  HYPERLINK \l "_Toc139253852"  6.0 Exposure Characterization/Assessment
  PAGEREF _Toc139253852 \h  39

  HYPERLINK \l "_Toc139253853"  6.1 Dietary Exposure/Risk Pathway
PAGEREF _Toc139253853 \h  39

  HYPERLINK \l "_Toc139253854"  6.1.1 Residue Profile	  PAGEREF
_Toc139253854 \h  40

  HYPERLINK \l "_Toc139253855"  6.1.2 Acute and Chronic Dietary Exposure
and Risk	  PAGEREF _Toc139253855 \h  40

  HYPERLINK \l "_Toc139253856"  <IP_ADDRESS> Acute Dietary Exposure Results
and Characterization	  PAGEREF _Toc139253856 \h  41

  HYPERLINK \l "_Toc139253857"  <IP_ADDRESS> Chronic Dietary Exposure Results
and Characterization	  PAGEREF _Toc139253857 \h  41

  HYPERLINK \l "_Toc139253858"  <IP_ADDRESS> Cancer Dietary Exposure Results
and Characterization	  PAGEREF _Toc139253858 \h  42

  HYPERLINK \l "_Toc139253859"  6.2 Water Exposure/Risk Pathway
PAGEREF _Toc139253859 \h  42

  HYPERLINK \l "_Toc139253860"  6.2.1 Environmental Fate	  PAGEREF
_Toc139253860 \h  42

  HYPERLINK \l "_Toc139253861"  6.2.2 Drinking Water Estimates	  PAGEREF
_Toc139253861 \h  43

  HYPERLINK \l "_Toc139253862"  6.2.3 Monitoring Data and Piscicide Use
 PAGEREF _Toc139253862 \h  43

  HYPERLINK \l "_Toc139253863"  6.2.4. Drinking Water Treatment
PAGEREF _Toc139253863 \h  44

  HYPERLINK \l "_Toc139253864"  6.3 Residential (Non-Occupational)
Exposure/Risk Pathway	  PAGEREF _Toc139253864 \h  44

  HYPERLINK \l "_Toc139253865"  6.3.1 Residential Handler Exposures and
Risks	  PAGEREF _Toc139253865 \h  44

  HYPERLINK \l "_Toc139253866"  6.3.2 Residential (Recreational)
Postapplication Exposures and Risks	  PAGEREF _Toc139253866 \h  44

  HYPERLINK \l "_Toc139253867"  6.3.3 Spray Drift	  PAGEREF
_Toc139253867 \h  46

  HYPERLINK \l "_Toc139253868"  7.0 Aggregate Risk Assessments and Risk
Characterization	  PAGEREF _Toc139253868 \h  47

  HYPERLINK \l "_Toc139253869"  8.0 Cumulative Risk
Characterization/Assessment	  PAGEREF _Toc139253869 \h  47

  HYPERLINK \l "_Toc139253870"  9.0 Occupational Exposure/Risk Pathway
PAGEREF _Toc139253870 \h  47

  HYPERLINK \l "_Toc139253871"  9.1.1 Short/Intermediate-Term Handler
Risks	  PAGEREF _Toc139253871 \h  49

  HYPERLINK \l "_Toc139253872"  9.2 Short- and Intermediate-term
Noncancer Postapplication Risk	  PAGEREF _Toc139253872 \h  53

  HYPERLINK \l "_Toc139253873"  10.0 Data Needs and Label Requirements
PAGEREF _Toc139253873 \h  53

  HYPERLINK \l "_Toc139253874"  10.1 Toxicology	  PAGEREF _Toc139253874
\h  53

  HYPERLINK \l "_Toc139253875"  10.2 Residue Chemistry	  PAGEREF
_Toc139253875 \h  53

  HYPERLINK \l "_Toc139253876"  10.3 Occupational/Residential Exposure
PAGEREF _Toc139253876 \h  54

  HYPERLINK \l "_Toc139253877"  11.0 Attachments	  PAGEREF _Toc139253877
\h  55

  HYPERLINK \l "_Toc139253878"  12.0 References	  PAGEREF _Toc139253878
\h  56

  HYPERLINK \l "_Toc139253879"  Appendix A: Executive Summaries for
Studies not Highlighted in Document and Toxicological Profile.	  PAGEREF
_Toc139253879 \h  57

 1.0 Executive Summary

Rotenone labels currently contain uses on home gardens for insect
control and on pets for lice and tick control.  Rotenone is also
currently registered for use on 91 food crops and on livestock and was
exempt from the need to establish tolerances until the passage of the
Food Quality Protection Act (FQPA).  However, these uses are no longer
being supported.  The Agency received requests dated March 7, 2006;
March 17, 2006; and April 5, 2006 from the technical registrants
Prentiss Incorporated, Foreign Domestic Chemicals Corporation, and Tifa
International, LLC, respectively, to cancel registrations of the
following rotenone products: EPA Reg. Nos. 655-3, 655-69, 655-421,
655-422, 655-691, 655-795, 655-803, 655-804, 655-805, 655-806, 655-807,
655-808, 6458-1, 6458-5, 6458-6, 82397-1, 82397-2, 82397-3, 82397-4, and
82397-5.  Rotenone is a non-specific botanical
insecticide/miticide/piscicide used to control flying and crawling
insects and fish.  Specifically, the rotenone registrants request
termination of rotenone uses that include formulations for livestock
use, residential and homeowner uses, domestic pet uses, and all other
uses, except for the piscicide uses, because they choose not to support
these uses.  Foreign Domestic Chemicals Corporation conditioned their
request upon the allowance for use of existing stocks until March 11,
2008.  The cancelled uses of rotenone were previously assessed in the
January 24, 2006 risk assessment (DP barcode D307385), which can be
found on EPA’s website.  The piscicidal use of rotenone is the subject
of this risk assessment.

Rotenone is a naturally occurring compound that is present in a number
of plants.  This botanical pesticide is derived from the roots of Derris
spp., Lonchocarpus spp., and Tephrosia spp., found primarily in
Malaysia, South America, and East Africa, respectively.  Under the
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), the Federal
government has registered rotenone, a List A chemical, since 1947.
Rotenone is a General Use Pesticide (GUP), but use for fish control, is
a restricted use and applications must be made by certified applicators
only.  It can be rapidly degraded in soil, water, and by sunlight,
usually within 2-5 days.  However, limited environmental fate data show
that, under some conditions (particularly in cold water), rotenone
and/or its metabolites may persist for as long as 6 months.

Most current Chemical Statements of Formula (CSFs) either do not list,
or do not quantify, the impurities.  There are risk concerns for
impurities, in general.  Batch analysis of the various formulations is
required, with the specific impurities identified, and levels
quantified.  When new CSFs, in compliance with item 10 of Form 8570-4,
are submitted, the risk assessment will be revised to include any
impurities of concern.

The toxicology database for rotenone is not complete with data gaps
existing for chronic dog, developmental toxicity (non-rodent), dermal
penetration, and repeated-dose dermal toxicity studies.   In special
studies, on one strain of rat, by the intravenous and subcutaneous
routes, exposure to rotenone produced behavioral, biochemical, and
neuropathological effects that resemble Parkinson’s disease in humans.
 While neither route of exposure is relevant to humans, the intravenous
route may mimic inhalation exposure, which is a route of concern with
rotenone. The only available inhalation toxicity study is an acute LC50
in the rat (Category I).  The current database includes guideline
studies via the oral route of exposure that typically do not include the
Functional Observational Battery (FOB) or neurotoxicity parameters.  In
addition, inhalation exposure can be a major route of exposure for some
uses and no subchronic inhalation toxicity studies are available for
rotenone.  The agricultural and residential uses for which inhalation
exposure is greatest, and of potential concern, are no longer being
supported.  A data call-in (DCI) was issued (02/09/2004) requiring a
21-day inhalation neurotoxicity study in the Lewis rat.  That DCI
remains unfulfilled and a submitted data waiver was denied.  The
toxicity database for rotenone is marginally adequate for selecting
toxicity endpoints for the risk assessment.  However, none of the
available studies suitable for risk assessment purposes are adequate to
address the neurotoxicity concerns.  The endpoints selected are based on
decreased pup body weight and body weight gain, and increased
resorptions.  Rotenone is classified as Group E carcinogen (evidence of
non-carcinogenicity for humans).  The supported piscicide use is
expected to reduce potential exposures by all routes though additional
mitigation measures and monitoring are still needed.  Therefore, the
inhalation neurotoxicity study and all other toxicity data requirements
are held in reserve (may be called in later) pending the outcome of
monitoring and further mitigation measures.

Residue chemistry data have not been addressed because all food uses
have been cancelled.  Environmental fate data, reviewed by EFED, show
that though the parent rotenone is photolytic and not persistent,
several degradates can be formed.  The only major degradate identified
is rotenolone, or specific rotenolone isomers (> 10%).  Structure
Activity Relationship (SAR) analysis indicates that all of the
metabolites identified in the environmental fate data (see Section 3.0)
are expected to be of equal or less toxicity than the parent rotenone.

The fate and transport properties of rotenone in the environment are not
well understood.  Rotenone does degrade rapidly by aqueous photolysis
and the photolysis half-life is less than one day.  There are no
reliable data on the microbial degradation of rotenone.  There is
evidence however that the metabolite rotenolone forms on plant surfaces
by hydrolysis.  Uncharacterized residues in unacceptable soil and
aquatic metabolism studies suggest that other degradates are formed, but
the identities and amounts are unknown.  Rotenone does not appear to
bioaccumulate in animals.

EFED provided HED with an estimated drinking water concentration (EDWC)
of 200 ppb in surface water based on the solubility of rotenone in
water.  It is also worth noting that the maximum application rate for
the piscicidal use of rotenone (250 ppb) exceeds the solubility of
rotenone. The remaining rotenone above the solubility limit is likely
either suspended or in an emulsion. In either case, the
suspended/emulsified rotenone will be less available for metabolism or
hydrolysis than that in the dissolved phase.

Based on the registrants’ proposed support of the piscicide use only,
a dietary risk assessment was conducted that estimates acute dietary
risks resulting from direct applications of rotenone to, or adjacent to,
bodies of water and drinking water consumption.  An acute deterministic
assessment was conducted using the Dietary Exposure Evaluation Model
(DEEM), which uses drinking water consumption data from the United
States Department of Agriculture (USDA) surveys and incorporated
estimated drinking water concentrations (EDWC) provided by EFED.  Food
uses of rotenone are not being supported, therefore, dietary (food)
exposure is not expected; and the Food Quality Protection Act (FQPA) of
1996 does not apply.

Conservative acute dietary (drinking water alone) exposure analyses were
performed in order to determine the potential exposure and risks
resulting from the piscicide use of rotenone.  For acute exposures, HED
is concerned when estimated dietary risk exceeds 100% of the reference
dose (RfD).  An appropriate acute endpoint for the general population,
including infants and children, was not identified in the available
toxicity studies; however, an acute analysis was performed for the
population subgroup females 13-49 years of age as increased incidence of
resorptions in a mouse developmental study is applicable to women of
childbearing age.  Acute dietary (drinking water alone) risk estimates
calculated for females 13-49 years of age are 65% of the aRfD and are
below the HED’s level of concern (100% aRfD) at the 95th exposure
percentile.  It is appropriate to consider the 95th percentile because
the analysis is deterministic and unrefined.

The chronic dietary risk analysis was complicated by the variability of
the degradation of rotenone under differing environmental conditions;
consequently, chronic risk estimates were not quantified using
DEEM-FCID.  Under all conditions, it was assumed that rotenone could
reach drinking water intakes (within 1 day) and potentially pose risks
from consumption of rotenone contaminated drinking water.  Rotenone
degrades more rapidly under warm water conditions and less rapidly under
cold water (4-5o C) conditions.  Using the chronic dietary endpoint and
conservative assumptions concerning drinking water consumption (1 L/day
for infants and children; 2 L/day for adults) by all population
subgroups, HED determined that chronic drinking water exposures greater
than 40 ppb could pose a potential risk of concern (> 100% cRFD) to the
most highly exposed population subgroup, children 1-2 years of age.
Information provided by EFED shows that chronic EDWCs are expected to
exceed 40 ppb for 4 days under warm water conditions, and for 53 days
under cold water conditions.  Data collected in association with
piscicidal application to Lake Davis in California show that 40 ppb
would be exceeded for up to 27 days.

The classification of carcinogenic potential for rotenone is “not
likely to be carcinogenic in humans,” based on the lack of evidence of
carcinogenicity in rats and mice; therefore, a cancer dietary analysis
was not performed.

  SEQ CHAPTER \h \r 1 Products containing rotenone are being supported
for the piscicidal use only.  As a result of the piscicidal use of
rotenone, adults and children may be exposed to rotenone when contacting
rotenone-treated waters through swimming.  Risk assessments were
conducted to reflect potential exposures to adult occupational handlers
and potential recreational postapplication exposure to adults and
children of varying ages.

The results of the recreational postapplication assessment indicate that
some of the risks are of concern [i.e., Margins of Exposure (MOEs) are
less than 1000].  Specifically, short-term MOEs exceed HED’s level of
concern for all toddler swimming scenarios (MOEs < 1000).  The
Environmental Fate and Effects Division (EFED) calculated the number of
days it would take to reach a rotenone concentration which results in
acceptable toddler MOEs (170 ppb of rotenone results in an MOE of 1000).
 This is done by assuming that the dissipation rate for rotenone in a
warm water pond is 1.5 days, as seen in the aquatic dissipation study.
The time it takes for the rotenone to dissipate (in 25oC water) to 170
ppb from 200 ppb is 0.35 days and from 250 ppb is 0.89 days.

Food uses of rotenone are not being supported, therefore, dietary (food)
exposure is not expected; and the Food Quality Protection Act (FQPA) of
1996 does not apply.  Since FQPA does not apply,   SEQ CHAPTER \h \r 1
HED does not need to aggregate pesticide exposures and risks from other
sources of exposure (drinking water and residential exposures).

It has been determined that exposure to pesticide handlers is likely
during the occupational use of rotenone in aquatic environments.  The
anticipated use patterns and current labeling indicate several
occupational exposure scenarios based on the types of equipment and
techniques that can potentially be used for rotenone applications.  For
applications to aquatic sites (liquid applications), combined dermal and
inhalation risks to mixers/loaders and aerial applicators, generally did
not exceed HED’s level of concern at some level of risk mitigation.
For applications to aquatic sites (wettable powder applications),
combined dermal and inhalation risks to mixers/loaders, generally
exceeded HED’s level of concern even at maximum risk mitigation.  Many
of the mixer/loader/applicator scenarios for aquatic sites (liquid and
wettable powder applications) also exceeded HED’s level of concern
even at maximum risk mitigation.  In particular, HED has serious
concerns for any scenario that involves open mixing/loading of wettable
powder formulations of rotenone.  HED also has concerns for
mixing/loading/applying via backpack sprayers for both liquid and
wettable powder formulations.  Please see the January 24, 2006 risk
assessment (DP barcode D307385), to see the occupational risks to the
non-piscicidal uses of rotenone which are no longer being supported by
the registrants but, remain on current labels to permit depletion of
existing stocks.

HED expects minimal occupational postapplication exposure from the
piscicidal use of rotenone.  As a result, no quantitative assessment was
completed for occupational postapplication exposure.

In summary, the toxicity database is incomplete and a potentially
critical effect, neurotoxicity, cannot be addressed with the existing
database.  Identification and quantification of potential impurities in
rotenone formulations remains unresolved.  Though dietary (water only)
risks are not of concern, based on reasonable but conservative
assumptions, confirmatory data are and label amendments are also
recommended.  Recreational postapplication risks (i.e., swimming) are of
concern for toddlers.  There are also some occupational handler risks
that exceed HED’s level of concern.

  SEQ CHAPTER \h \r 1 2.0 Ingredient Profile

Rotenone is a non-specific botanical insecticide with some acaricidal
properties.  Rotenone is used for fish eradications as part of water
body management.  Rotenone is a rotenoid plant extract obtained from
such species as barbasco, cube, haiari, nekoe, and timbo.  These plants
are members of the pea (Leguminosae) family.  Rotenone-containing
extracts are taken from the roots, seeds, and leaves of the various
plants.  Rotenone is only slightly insoluble in water.  Rotenone is used
either as a powder from ground-up plant roots or extracted from roots
and formulated as a crystalline or liquid preparation.  Formulations
include crystalline preparations (approximately 95% pure), emulsified
solutions (approximately 50% pure), and dusts (approximately 0.75% to 5%
pure).

	2.1 Summary of Registered/Proposed Uses  tc "1.6.1	End-Use Products "
\l 3

Rotenone is a widely used as a piscicide in the United States.  Rotenone
piscicide products are formulated as liquids and as wettable powders.

2.1.1	Registered Use Categories and Sites  tc "1.6.2	Registered Use
Categories and Sites " \l 3

Rotenone is currently registered for use in a variety of occupational
and residential scenarios, however, in memos dated (March 7, 2006; March
17, 2006; and April 5, 2006) the technical registrants (Prentiss, Inc.;
Foreign Domestic Chemicals Corporation; and Tifa Limited) for rotenone
voluntarily cancelled all uses of rotenone except for the piscicidal
uses.  This assessment deals with occupational populations that could be
potentially exposed while performing rotenone applications as well as
residential populations that may be exposed to rotenone during
postapplication time periods (i.e., swimming).  The cancelled uses of
rotenone were previously assessed in the January 24, 2006 risk
assessment (DP barcode D307385), which can be found on EPA’s website.

Currently, rotenone is used as a piscicide in two main areas.  The first
use is when rotenone is used in water body (lakes, ponds, streams, etc.)
fish management strategies.  Rotenone is typically used in this manner
when a water body has an unbalanced fish population or a non-native
introduced species threatens native fish populations.  The second use is
when rotenone is used in catfish aquaculture.  The use of rotenone in
catfish aquaculture is typically limited to treatment of the aquaculture
ponds in the spring prior to stocking of a new “crop” of catfish
fry.  The purpose of this treatment is to eliminate undesirable fish
species (i.e., shad, blue gills, and mud cats) that would compete with
the catfish fry.

2.1.2	Application Methods and Rates tc "1.6.3	Application Methods " \l 3

Piscicidal applications of rotenone are applied using several types of
application equipment – including helicopters, closed system
aspirators, boats with over-surface booms, boats with underwater hoses,
drip bars (in rivers and streams) and backpack sprayers.  Table 2.1
includes a description of application methods and rates that are
currently being approved for use by the rotenone technical registrants.
These rates and methods apply to use of rotenone in fish management
strategies as well as catfish aquaculture.

The area treated per day throughout this assessment is described as
acre-foot/day (A-ft/day) for lake, pond, and reservoir applications and
as cubic feet/day (ft3/day) for stream and river applications.
Acre-foot/day numbers are calculated by taking the number of surface
acres treated per day and multiplying by the depth of the lake being
treated, which was assumed by HED to be 5 feet.  For example, with
helicopter applications, HED assumed the high end of the treatment range
would be 10 surface acres and when this number is multiplied by the
depth of 5 feet, a value of 50 A-ft/day is acquired.  Similar
calculations were performed for river and stream applications but for
these applications HED used the length of stream treated, the depth of
stream, and the width of stream.  For example, with backpack
applications, HED estimated that the length of stream that could be
treated in one day is 10,560 ft (2 miles) and when this number is
multiplied by the 2 foot depth of the stream and the 10 foot width of
the stream, a value of 211,200 ft3 is acquired.

Table 2.1. Summary of Maximum Application Rates for Registered
Rotenone Aquatic Uses

Use Site	Target of Application	Maximum Application Rate 1	Formulation
Application Equipment	Area Treated or Amount Handled Per Day 2

Lakes, ponds, reservoirs	Fish	0.68 lb ai/A-ft

&

0.54 lb ai/A-ft	Liquid	Helicopter	50 A-ft/day

&

25 A-ft/day

Boat: over-surface boom	500 A-ft/day

&

250 A-ft/day

Boat: underwater hoses	500 A-ft/day

&

250 A-ft/day

Backpack	10 A-ft/day

Closed system aspirator	500 A-ft/day

&

250 A-ft/day

0.68 lb ai/A-ft

&

0.54 lb ai/A-ft	WP	Boat: over-surface boom	500 A-ft/day

&

250 A-ft/day

Boat: underwater hoses	500 A-ft/day

&

250 A-ft/day

Backpack	10 A-ft/day

Closed system aspirator	500 A-ft/day

&

250 A-ft/day

Moving water (streams)

0.000016 lb ai/ft3

&

0.000013 lb ai/ft3	Liquid	Backpack	211,200 ft3

Drip bar

	0.000016 lb ai/ft3

&

0.000013 lb ai/ft3	WP	Backpack

	Drip bar

	Seeps or Springs

	WP	Volumetric container

(powder/sand/gelatin paste)

	1	Maximum of two applications of rotenone per year.

2	Area treated per day values for all application methods except boats
are based on personal contact with Brian Finlayson, California
Department of Fish and Game (1/9/06).  Area treated per day values for
boat application methods are based on HED professional judgment.

	2.2 Structure and Nomenclature  tc "2.2	Structure and Nomenclature " \l
2

Empirical formula	C23 H22 O6

Common name	Rotenone

Trade names	Chem-fish, Curex flea duster, Derrin, Cenol Garden Dust,
Cuberol, Sinid, Tox-R, Noxfire, Cibe Extract, Rotacide, Fish Tox,
Chem-Mite, Green Cross Warbler Powder

IUPAC name
(2R,6aS,12aS)-1,2,6,6a,12,12a-hexahydro-2-isopropenyl-8,9-dimethoxychrom
eno[3,4-b]furo[2,3-h]chromen-6-one.

CAS name
(2R,6aS,12aS)-1,2,6,6a,12,12a-hexahydro-2-isopropenyl-8,9-dimethoxychrom
eno [3,4-b]furo[2,3-h]chromen-6-one

CAS Registry Number	83-79-4

Chemical Class	Rotenoid

Known Impurities of Concern	Extraction compounds may exist as impurities
in unspecified amounts

	2.3 Physical and Chemical Properties  tc "2.3	Physical and Chemical
Properties " \l 2

Table 2.3.    SEQ CHAPTER \h \r 1 Product Chemistry Data Summary Table
for Rotenone

OPPTS Guideline Numbers	Data Requirements: Rotenone

[Technical Grade of Active Ingredient]

CAS Number: 83-79-4

PC Code: 071003

Formula:  C23H22O6

	Master Record Identification [MRID]

Status

Results or *Deficiency

830.1550 	Product Identity and Composition  	441115-01	Acceptable

	830.1600

	Description of Materials Used to Produce the Product	441115-01
Acceptable

	830.1620 	Description of Production Process	441115-01	Acceptable

	830.1650 	Description of Formulation Process	446528-01	Acceptable

	830.1670 	Discussion of Formation of Impurities	441115-01	Acceptable

	830.1700 	Preliminary Analysis	441386-01	Acceptable

	830.1750 	Certified Limits	443953-01	Acceptable

	830.1800 	Enforcement Analytical Method	447265-01,  445108-01
Acceptable

	830.1900 	Submittal of Samples

Acceptable	44.2% Technical Grade Active Ingredient  Expires: 02/22/2006,
EPA Repository, Ft. Meade, MD

830.6302 	Color	438180-02	Acceptable	 Off White to Tan

830.6303 	Physical State	438180-02	Acceptable	Powder

830.6304 	Odor	438180-02	Acceptable	Wet chalk

830.6313  	Stability to normal and elevated temperatures, metals and
metal ions	441237-05	Acceptable	Temp(s) = No appearance change; the loss
was less than 5%.

Metals = No appearance change, the loss was about 5%.

830.7000 	pH	441308-01, 446528-01	Not Applicable	 Insoluble in water

830.7050  	UV/VIS absorption

Acceptable	480 at 235nm & 550 at 292 nm;

Ref: Clarke’s Analysis of Drugs and Poisons; London Pharmaceutical
Press Electronic Version 2004

830.7200 	Melting Point/Melting Range	441237-02	Acceptable	160 oC - 163
oC

830.7220 	Boiling Point/Boiling Point Range

Not Applicable	See 830.7200

830.7300 	Density/Relative Density/Bulk Density	438180-02	Acceptable
Fluffy  --   0.2400 g/cm3; 14.70 lb/cu ft

Compacted  --  4500g/cm3; 28.10 lb/cu ft

830.7370 	Dissociation  Constant	447181-01	Acceptable	None at pH 2-12
(OECD Method No. 112)

830.7550 	Partition coefficient (n-octanol /water) shake flask method
441237-04	Acceptable	K o/w       Log P = 4.16

830.7560 	Partition coefficient (n-octanol /water) generator column
method

	See Guideline 830.7550

830.7570 	Partition coefficient (n-octanol /water) estimation by liquid
chromatography

	See Guideline 830.7550

830.7840 	Water Solubility: Column Elution Method; Shake Flask Method
441237-03	Acceptable	Solvent = Water 	Temperature  = 20 ºC

Avg. Solubility = 0.142 µg/ml

830.7860 	Water solubility, generator column method

	See Guideline 830.7840

830.7950 	Vapor pressure	446529-01	Not Applicable

3.0 Metabolism Assessment

	3.1 Comparative Metabolic Profile  tc "3.1 	Comparative Metabolic
Profile " \l 2

The qualitative nature of the residue in living organisms is not
understood.  However, the rapidity of rotenone degradation in the
environment may limit the potential for uptake by macroorganisms, and
therefore may limit the potential for metabolism except by microbes.
Enzymatic metabolism of the sort that might occur in living organisms
may result in the same biotransformation pathway as other degradative
processes.  It is not known whether metabolism of rotenone by living
organisms proceeds rapidly or whether it would give rise initially to
rotenolone, and then to polar products as it occurs in the environment.

	3.2 Nature of the Residue in Foods  tc "3.2	Nature of the Residue in
Foods " \l 2

Food uses are no longer being supported by the registrants (see section
2.1).  HED’s analysis of the available crop and livestock residue and
metabolism data may be found in ROTENONE: Phase 4 HED Chapter of the
Reregistration Eligibility Decision Document (RED).  PC Code: 071003.
DP Barcode: D307385.  January 24, 2006.

	3.3 Rat Metabolism  tc "3.3	Rat Metabolism " \l 2

There are no acceptable guideline metabolism studies available for
rotenone.  However, an Acceptable/Non-guideline metabolism and
pharmacokinetics study is available for rotenone (rat).  The primary
route of excretion was in the feces with polar metabolites being
identified in the feces.  Metabolic profiles for the seven metabolites
found in the feces were not obtained.  In conjunction with fecal
elimination, rotenone underwent extensive enterohepatic circulation.
Tissue accumulation was low, typically less than 1% of the administered
dose.

A definitive target organ has not been identified although the mechanism
of action is well known.  Rotenone uncouples oxidative phosphorylation
by blocking electron transport at complex I within the mitochondria.
Numerous published literature studies conducted over the past ten years
indicate rotenone inhibits the activity of complex I of the
mitochondrial electron transfer chain but also reproduces features of
Parkinson’s disease (PD), including selective nigrostriatal
dopaminergic degeneration and microglial activation [Sherer TB, Betarbet
R, Kim JH, Greenamyre JT (2003). Selective microglial activation in the
rat rotenone model of Parkinson’s disease. Neuroscience Letters 341
87-90].  More recently, rotenone has been associated with features of
Parkinson’s disease by the development of a-synuclein-positive
cytoplasmic inclusions [Spillantini et al., 1997.  Spillantini MG,
Schmidt ML, Lee VM, Trojanawski JQ, Jakes R, Goedert M (1997).
Alpha-synuclein in Lewy bodies.  Nature 388:839-840.; Wooten, 1997
Wooten GF (1997). Neurochemistry and neuropharmacology of Parkinsons’s
disease. In: Movement disorders:neurologic principles and practice
(Watts RL, Koller WC, eds), pp 153-160. New York: McGraw-Hill.; Sherer
et al., 2003a Sherer TB, Kim JH, Betarbet R, Greenamyre JT (2003).
Subcutaneous rotenone exposure causes highly selective dopaminergic
degeneration and alpha-synuclein aggression. Exp Neurol 17:9-16., Sherer
et al., 2003b Sherer TB, Betarbet R, Testa C, Byoung BS, Richardson JR,
Kim JH, Miller GW, Yagi T, Matsuno-Yagi A, Greenamyre JT (2003).
Mechanism of toxicity in Rotenone models of Parkinson’s disease. The
Journal of Neuroscience 23(34):10756-10764.), another feature of PD.]

	3.4 Environmental Degradation

The primary degradate identified in the environmental fate studies is
rotenolone.  Rotenolone is believed to be a complex of related
stereoisomers; at least four, and perhaps more occur.  Rotenolone, or
specific rotenolone isomers, are the only identified major (> 10%)
degradates. Rotenolone occurs at up to 80% of the applied parent in the
anaerobic aquatic metabolism study.  Limited ecological test data show
rotenolone to be one tenth as lethal to fish as rotenone (CDFG 1991).
The other identified degradates, in addition to CO2, are listed below.
Many of these were identified only in a non-guideline photodegradation
study on bean leaf.

Table 3.4  Rotenone Degradation Products

Metabolite	Amount	Study

Rotenolone	33-50% of applied	MRID# 00141409 (hydrolysis)

Rotenone

	13.5% of applied

,12a-rotenolone	4.8% of applied	MRID# 41125402 (photodegradation -
bean leaf)

6a,12a-Rotenolone	11% of applied	MRID# 41125402 (photodegradation
- bean leaf)

6a,12a-rotenolone	0.4% of applied	MRID# 41125402 (photodegradation
- bean leaf)

Rotenone	0.7% of applied	MRID# 41125402 (photodegradation - bean leaf)

Rotenolone	25% of applied	MRID# 00141274 (Aerobic aquatic metabolism)

Rotenolone	80% of applied	MRID# 00141273 (Anaerobic aquatic metabolism)

Rotenolone	Identified, not quantified	MRID# 455801073 (Bioaccumulation
in fish)

6',7'-dihydro-6',7' -dihydroxyrotenolone 	Identified, not quantified
MRID# 455801073 (Bioaccumulation in fish)

4.0 Hazard Characterization/Assessment

	4.1 Hazard Characterization  tc "4.1	Hazard Characterization " \l 2

4.1.1 Database Summary  tc "4.1.1  Database Summary " \l 3

	<IP_ADDRESS> Critical Studies (animal, human, general literature)

The acute toxicity profile for rotenone is complete.  Rotenone is
acutely toxic via the oral and inhalation routes of exposure (Toxicity
Category I), with females more sensitive than males to acute oral
toxicity.  Rotenone was neither corrosive nor irritating to the skin or
eye (Toxicity Category IV) and is not a dermal sensitizer.

The database for rotenone is not complete with data gaps existing for
chronic dog, developmental toxicity (non-rodent), dermal penetration,
and 21-day dermal toxicity studies.  Acceptable oral studies for
rotenone include an oral 90-day subchronic (dog), oral developmental
toxicity (rat and mouse), reproduction (rat), carcinogenicity (rat and
mouse), and combined chronic/cancer (rat) study.  Rotenone was negative
in several in vitro mutagenicity assays.

In a special continuous intravenous study (Betarbet et al., 2000, MRID#
45279501) with Lewis rats, exposure to rotenone (2.5-2.75 mg/kg/day)
produced behavioral, biochemical, and neuropathological effects that
resemble Parkinson’s disease in humans.  Intravenous rotenone induced
specific neurodegenerative lesions in nigrostriatal dopaminergic
neurons.  The microscopic lesions progressed over time and correlated
with complex I inhibition.  Clinical signs in affected animals included
hypoactivity, unsteady gait, and hunched posture.  Since the publication
of the Betarbet study in 2000, several laboratories have published
studies verifying the systemic complex I inhibition caused by rotenone,
including dopaminergic neurotoxicity, and currently use rotenone as a
model (in vitro and in vivo) for Parkinson’s disease.  While the
intravenous route of exposure is not relevant to humans, it may mimic
inhalation exposure, which is a route of concern with rotenone.
Inhalation is the most direct point-of-entry for absorption, similar to
the intravenous route, with distribution prior to metabolism of the
chemical and therefore most comparable to the intravenous route.
Inhaled substances may pass directly into the bloodstream and circulate
once through the body, including the brain, before they reach the liver,
where most materials are substantially metabolized.  The only available
inhalation toxicity study is an acute LC50 study in the rat.  Therefore,
a DCI (Data Call In) was issued (02/09/2004) requesting a 21-day
inhalation neurotoxicity study in the Lewis rat.

	<IP_ADDRESS> Metabolism, toxicokinetics, mode of action data

There are no guideline metabolism studies available for rotenone.
However, an Acceptable/Non-guideline metabolism and pharmacokinetics
study is available for rotenone (rat).  The primary route of excretion
was in the feces with polar metabolites being identified in the feces.
Structural characterization of the seven metabolites found in the feces
were not obtained.  In conjunction with fecal elimination, rotenone
underwent extensive enterohepatic circulation.  Tissue accumulation was
low, typically less than 1% of the administered dose.

A definitive target organ has not been identified although it is known
that rotenone uncouples oxidative phosphorylation by blocking electron
transport at complex I within the mitochondria.  Numerous published
literature studies within the past ten years indicate rotenone inhibits
the activity of complex I of the mitochondrial electron transfer chain
and also reproduces features of Parkinson’s disease (PD), including
selective nigrostriatal dopaminergic degeneration and microglial
activation.  More recently, rotenone has been associated with features
of PD by the development of α-synuclein-positive cytoplasmic inclusions
(Spillantini etal., 1997; Wooten, 1997; Sherer et al., 2003a, Sherer et
al., 2003b), another feature of PD.  It is currently not understood how
the mechanism for rotenone translates into the etiology of PD.

	<IP_ADDRESS> Sufficiency of studies/data

The toxicity database for rotenone is adequate for selecting toxicity
endpoints for the risk assessment.  However, the available oral studies
defining the hazard component of this risk assessment are not adequate
to assess neurotoxicity.  The current database includes guideline
studies via the oral route of exposure that typically do not include the
Functional Observational Battery (FOB) or neurotoxicity parameters.  In
addition, inhalation exposure can be a major route of exposure for some
uses and no subchronic inhalation toxicity studies are available for
rotenone.  As stated earlier, published literature has reported
behavioral effects and brain lesions in the Lewis rat, resembling PD in
humans, after continuous intravenous, and recently subcutaneous,
exposure to rotenone.  In the subcutaneous study, decreased survival
rate and behavioral impairment were observed in male Lewis rats
beginning with subcutaneous administration of 2 mg/kg rotenone (in DMSO)
for 21-days (lowest dose tested).

	4.1.2 Toxicological Effects

As stated above, a definitive target organ has not been identified
although rotenone uncouples oxidative phosphorylation by blocking
electron transport at complex I within the mitochondria.

The major toxicological concern that HED has with rotenone is the
potential to cause PD in humans.  PD is not normally seen in rats and
yet studies in the Lewis rat clearly show PD-like effects that cannot be
ignored.  HED is uncertain whether these findings are applicable to
humans and by what route.  Minimal systemic toxicity has been observed
in subchronic and chronic animal studies.  The most common effect in
animal studies from intermediate- or long-term oral exposure was a
decrease in body weight or body weight gain.  Rats were more sensitive
than mice and in both species, females were more sensitive than males to
effects on body weight.  In chronic studies, the basis for the lowest
observed adverse effect levels (LOAELs) was a decrease in body weight
and body weight gain by female rats (1.88 mg/kg/day) and male and female
mice (111 and 124 mg/kg/day, respectively).  The no observed adverse
effect level (NOAEL) for chronic toxicity in rats was 0.375 mg/kg/day
but a NOAEL was not identified in mice.

Decreased maternal body weight gain was also observed in developmental
toxicity studies with rats and mice (1.5 and 24 mg/kg/day,
respectively).  Additionally, rats showed clinical signs of toxicity
(salivation and rubbing the face and paws after treatment) at maternal
doses as low as 0.75 mg/kg/day.  Developmental toxicity was observed as
decreased fetal body weight (23%) in rats (maternal 6 mg/kg/day) and
increased resorptions (3.8 vs. 0.5 controls) with correspondingly fewer
live fetuses/litter in mice (8.2 vs. 10.8 controls, maternal 24
mg/kg/day).  No treatment-related structural external, visceral, or
skeletal abnormalities were found in fetuses from treated dams.

In a two-generation reproductive toxicity study (rat) with rotenone,
adult and offspring toxicity were observed at doses greater than 3.0
mg/kg/day.  The main effect in both parental animals and pups was
decreased body weight and body weight gain.  Females were more sensitive
than males and the magnitude of effects was similar between generations.
 Parental toxicity was indicated by decreased absolute body weight and
body weight gain for the high-dose males and females (4.8 and 6.2
mg/kg/day, respectively) and the mid-dose females (3.0 mg/kg/day) of
both generations.  Food consumption was only marginally affected and
mainly in the high-dose groups.  Decreased maternal weight gain by the
6.2-mg/kg/day F0 and F1 dams during gestation correlated with a decrease
in the mean number of live pups/litter in the high-dose groups of both
generations (9.7-9.9 vs. 11.4-11.8 for the controls).  F1 and F2
offspring body weight was slightly or significantly less than that of
controls for the 6.2-mg/kg/day pups beginning at birth and for the
3.0-mg/kg/day pups beginning on post natal day (PND) 4.  Body weight
gain was reduced in the mid- (20-26%) and high-dose (40-60%) pups of
both generations throughout lactation beginning with the interval PND
0-4.

None of the results from the available studies, except the acute oral
toxicity study, showed evidence of neurotoxicity.  However, as discussed
earlier, rotenone administered via the intravenous or subcutaneous route
of exposure in male Lewis rats produced behavioral, biochemical, and
neuropathological effects that resemble PD in humans.  Rotenone
administered intravenously at 2.5-2.75 mg/kg/day induced specific
neurodegenerative lesions in nigrostriatal dopaminergic neurons.  The
microscopic lesions progressed over time and correlated with complex I
inhibition.  Clinical signs in affected animals included hypoactivity,
unsteady gait, and hunched posture.  Inhalation is the most direct
point-of-entry for absorption similar to the intravenous route with
distribution prior to metabolism of the chemical and therefore, most
comparable to the intravenous route.  Inhaled substances may pass
directly into the bloodstream and circulate once through the body,
including the brain, before they reach the liver, where most materials
are substantially metabolized.

Rotenone is classified as Group E (evidence of non-carcinogenicity for
humans) (CARC 10/05/1988).  No evidence for carcinogenicity was seen in
mice or rats from available carcinogenicity studies.  Administration of
rotenone to both species for up to two years did not result in an
increase in overall tumor incidence or increase the incidence of any
specific type of tumor.  The chemical was negative for gene mutation in
two studies with Salmonella typhimurium and for mitotic gene conversion
with Saccharomyces cerevisiae.  Micronucleus formation was not induced
in the bone marrow of mice.  Rotenone also did not cause chromosomal
aberrations in CHO cells in vitro with or without activation or in bone
marrow cells from rats administered up to 7 mg/kg orally.   However,
both the rat and mouse micronucleus and bone marrow assays are
classified unacceptable/non-guideline since a maximum tolerated dose
(MTD) was not achieved in either speicies.  Positive results for gene
mutation were obtained only in mouse lymphoma cells, without metabolic
activation, at concentrations equal to and below those which also caused
significant cytotoxicity.

	4.1.3 Dose-response

Based on the registrants’ proposed support of the piscicide use only,
a dietary risk assessment was conducted that estimates acute and chronic
dietary risks resulting from direct applications of rotenone to, or
adjacent to, bodies of water and drinking water consumption.  Food uses
are not supported, therefore, the Food Quality Protection Act (FQPA) of
1996 does not apply.

A dose related decrease in weight gain was shown in the parental,
reproductive, and offspring endpoints in the two-generation reproduction
study.  Decreased fetal body weight was also evident at the highest dose
tested in the developmental toxicity study.  Both the cancer studies in
the mouse and rat showed a good dose-response in body weight decreases.
The body weight decrement of the offspring at birth from the rat
reproduction study was selected for the acute reference dose (RfD) for
females aged 13-49 years.  Parental body weight decrement from the
reproduction study was the selected adverse effect for the
intermediate-term oral and incidental oral, and short- and
intermediate-term inhalation exposure.  Decreased body weight and food
consumption from the chronic/oncogenicity study supports the chronic RfD
and long-term inhalation exposure endpoints.

Table 4.1.3a:  Acute Toxicity Data on Rotenone

Guideline No.	Study Type	MRID#(s)	Results	Toxicity Category

870.1100

81-1	Acute oral [rat]

99.23% a.i.	00145496	LD50 = 102 mg/kg (M)

LD50 = 39.5 mg/kg (F)	I

870.1200

81-2	Acute dermal [rabbit]

97.9% a.i.	43907501	LD50 = >5000 mg/kg	IV

870.1300

81-3	Acute inhalation [rat]

98% a.i.	43882601	LC50 = 0.0212 mg/L combined

LC50 = 0.0235 mg/L (M)

LC50 = 0.0194 mg/L (F)	I

870.2400

81-4	Acute eye irritation [rabbit]

97.9% a.i.	43907503	minimal, in unwashed eyes conjunctival irritation,
PIS 3.3 at 1 hr, cleared less than 24 hrs.	IV

870.2500.

81-5	Acute dermal irritation [rabbit]

97.9% a.i.	43907504	PIS 0.08 at 1 hour which decreased to 0 at 72 hours
IV

870.2600

81-6	Skin sensitization [guinea pig]

98% a.i.	43817903	Not a dermal sensitizer	NA

Table 4.1.3b:  Subchronic, Chronic, Developmental, Reproductive and
Other Toxicity Profile on Rotenone

Guideline#/ Study Type	MRID# (year)/ Classification /Doses	Results

870.3100

82-1a

90-Day oral toxicity (rat)

Satisfied by MRID 00156739, 41657101 (83-5)

870.3150

82-1b

90-Day oral toxicity (dog)	00141406 (1980)

Acceptable/guideline

M&F: 0, 0.4, 2, 10 mg/kg/day	NOAEL = 0.4 mg/kg/day

LOAEL = 2 mg/kg/day based decreased body weight in mid-dose females
(20%) and high-dose males and females (30%) and treatment-related
inanition.

(duration of treatment was 26 weeks)

870.3200

82-2

21/28-Day dermal toxicity

Not Available/Data Gap

870.3250

82-3

90-Day dermal toxicity

Not Required

870.3465

82-4

90-Day inhalation toxicity

Not Required.  21/28-Day study with neurological parameters is required.

870.3700a

83-3a

Developmental Toxicity (rat)	00144294 (1982)

Acceptable/guideline

F: 0, 0.75, 1.5, 3, 6 mg/kg/day (GD 6-19)	Maternal NOAEL = not
identified

LOAEL = 0.75 mg/kg/day, based on clinical signs of toxicity (salivation,
rubbing of face and paws on cage in all groups).

Developmental NOAEL = 3 mg/kg/day

LOAEL = 6 mg/kg/day based on decreased fetal body weight (23%).

870.3700a

83-3a

Developmental Toxicity (mouse)	00141707 (1981) (main)

00145049 (1981) (range-finding)

Acceptable/guideline

F: 0, 3, 9, 15, 24 mg/kg/day (GD 6-17)	Maternal NOAEL = 15 mg/kg/day

LOAEL = 24 mg/kg/day, based on decreased body weight (10%) and body
weight gain  (41%), from range-finding study.

Developmental NOAEL = 15 mg/kg/day

LOAEL = 24 mg/kg/day, based on increased resorptions (3.8 vs. 0.5
controls), from range-finding study.

Acceptable when main and range-finding study considered together.

870.3700b

83-3b

Developmental Toxicity (non-rodent/rabbit)

Not Available/Data Gap

870.3800

83-4

Reproduction

(rat)	00141408 (1983)

Acceptable/guideline

F0: M: 0, 0.5, 2.4, 4.8 mg/kg/d

F0: F: 0, 0.6, 3.0, 6.2 mg/kg/day

F1 (M):0, 0.6, 3.1, 7 mg/kg/day

F1 (F): 0, 0.7, 3.7, 8.1 mg/kg/day	Parental/Systemic NOAEL (M/F) =
0.5/0.6 mg/kg/day

LOAEL (M/F) = 2.4/3.0 mg/kg/day based on decreased body weight (10-13%)
and body weight gain (16-25%).

Reproductive NOAEL (M/F) = 2.4/3.0 mg/kg/day

LOAEL (M/F) = 4.8/6.2 mg/kg/day based on decreased live pups/litter in
both generations (9.7-9.9 vs. 11.4-11.8 controls).

Offspring NOAEL (M/F) = 0.5/0.6 mg/kg/day

LOAEL (M/F) = 2.4/3.0 mg/kg/day based on decreased F1 and F2 pup body
weight (8-18%) and body weight gain (mid 20-26%; high 40-60%).

870.4100a

83-1a

Chronic toxicity

(rat)

Satisfied by MRID# 00156739, 41657101 (83-5)

870.4100b

83-1b

Chronic toxicity

(dog)

Not Available/Data Gap

870.4200

83-2a

Carcinogenicity

(rat)	40179801b/46274301

 (1986) NTP

Unacceptable/guideline

0, 38, 75 ppm

M: 0, 1.7, 3.4 mg/kg/day

F: 0, 1.8, 3.6 mg/kg/day	NOAEL (M/F) = 3.4/3.8 mg/kg/day

LOAEL = not identified

Animals could have tolerated a higher dose, MTD not achieved

No evidence of carcinogenicity

870.4200

83-2a

Carcinogenicity

(rat)	00143257 (1979)

Unacceptable/non-guideline

M&F: 0, 1.7, 3.0 mg/kg/day (i.p., 42 days, observed for 17 months)

M&F: 0, 1.7, 3.0 mg/kg/d (gavage, 42 days)	NOAEL = 3.0 mg/kg/day

LOAEL = not identified

Animals could have tolerated a higher dose, MTD not achieved

No evidence of carcinogenicity

870.4200

83-2b

Carcinogenicity

(mouse)	40179801a/46274301 (1986) NTP

Acceptable/guideline

0, 600, 1200 ppm

M: 0, 111, 242 mg/kg/day

F: 0, 124, 265 mg/kg/day	NOAEL = not identified

LOAEL (M/F) = 111/124mg/kg/day based on decreased body weight (low: (M)
6-12%, (F) 12-20%, high: (M) 12-17%, (F) 17-26%.

No evidence of carcinogenicity

870.4200

83-2b

Carcinogenicity

(hamster)	00143256 (1979)

Unacceptable/non-guideline

0, 125, 250, 500, 1000 ppm

M&F: 0, 10, 21, 42, 83 mg/kg/day (food factor of 0.083)	NOAEL = 42
mg/kg/day

LOAEL = 83 mg/kg/day based on decreased weight gain.

No evidence of carcinogenicity

Excessive mortality due to secondary infection; additional groups
administered 500 and 1000 ppm for 3 or 4 months were mated resulting in
no viable offspring at 1000 ppm and maternal neglect and cannibalization
at 500 ppm

870.4300

83-5

Chronic/Oncogenicity (rat)	00156739 (1985)

41657101 (1989 amendment)

Acceptable/guideline

0, 7.5, 37.5, 75 ppm

M&F: 0, 0.375, 1.88, 3.75 mg/kg/day (food factor of 0.05)	NOAEL  = 0.375
mg/kg/day

LOAEL  = 1.88 mg/kg/day, based on decreased body weight at termination
[M:7% (mid) and 15% (high); F: 24% (mid) and 42% (high)] and cumulative
weight gain [M: 10% (mid) and 20% (high); F: 31% (mid) and 55% (high)]
and food consumption in females [9% and 21% in mid and high,
respectively]

No evidence of carcinogenicity

Gene Mutation

84-2

870.5100

(Salmonella typhimurium)	40170506 (1988)

NTP study

Acceptable/guideline	No evidence of induced mutant colonies over
background for any tester strain at any concentration up to 10,000
μg/plate with and without metabolic activation; strains TA98, TA100,
TA1535, TA1537.

Gene Mutation

84-2

870.5100

(Salmonella typhimurium)	40170502 (1978)

Acceptable/guideline	No evidence of induced mutant over background for
any test strain at any concentration up to 10,000 μg/disk with and
without metabolic activation; strains TA98, TA100, TA1535, TA1537,
TA1538.

Gene Mutation

870.5300

84-2

(mouse lymphoma cells)	40170505 (1984)

Acceptable/guideline	Evidence of a concentration-related positive
response of induced mutant colonies over background at 0.25-8.0 μg/mL
without metabolic activation; significant cytotoxicity at 4 and 8
μg/mL.

Cytogenetics

870.5375

84-2

(Chinese hamster ovary)	40179801c (1986)

Acceptable/guideline	No evidence of chromosome aberrations up to 100
μg/mL without metabolic activation and 250 μg/mL with activation.

Cytogenetics

870.5385

84-2

(rat and mouse)	00093702 (1981)

Unacceptable/non-guideline	Maximum tolerated dose (MTD) was not achieved
in either the rat or mouse assays.  No evidence of induced
chromatid/chromosome aberrations in rat bone marrow cells up to 7.0
mg/kg; no significant increase in frequency of micronuclei in
erythrocytes from bone marrow of mice up to 80 mg/kg.

Micronucleus

870.5395

84-2

(mouse)	00093702 (1981)

Acceptable/guideline	Negative at oral doses of 0, 10, or 80 mg/kg

Mitotic gene conversion

870.5575

84-2

(Saccharomyces cerevisiae)	00144292 (1981)

Acceptable/guideline	No evidence of induced mutant colonies over
background for any test concentration up to 10,000 ug/plate with and
without metabolic activation. Limit dose 5000 μg/plate.

870.6200a

81-8

Acute neurotoxicity screening battery

Pending results of the subchronic inhalation neurotoxicity study.

870.6200b

82-7

Subchronic neurotoxicity screening battery

Requested, DCI 2/9/04 (GDCI-071003-20980)

-inhalation (rat)

870.6300

83-6

Developmental neurotoxicity

Study required pending results of the subchronic inhalation
neurotoxicity study.

870.7485

85-1

Metabolism and pharmacokinetics

(rat)	00145496 (1984)

Acceptable/non-guideline

0.01, 0.1, 5 mg/kg (oral and iv)	Primary route of excretion is in feces;
extensive enterohepatic circulation; some urinary excretion with females
greater than males; polar metabolites reported in feces but metabolites
not identified

870.7600

85-2

Dermal penetration

(rat)

Not Available/Data Gap

Special studies

Subacute neurotoxicity

(rat)	45279501 (Betarbet et al., 2000)

Acceptable/nonguideline

M: 2.5-2.75 mg/kg/day by i.v. infusion for 1-5 weeks	Behavioral,
biochemical, and neuropathological effects that resemble Parkinson’s
disease in humans; induction of specific neurodegenerative lesions in
nigrostriatal dopaminergic neurons

	4.2 Hazard Considerations

	4.2.1 Adequacy of the Toxicity Data Base

Data are adequate for evaluation of effects resulting from in utero and
postnatal exposure in rodents only.  Two acceptable developmental
toxicity studies have been conducted in rodents (mice and rats) and a
reproductive toxicity study in rodents (rats) is available.  It is noted
that a developmental toxicity study in nonrodents (rabbit) has not been
submitted.  In the available studies, developmental toxicity was
observed in both rats and mice at doses greater than or equal to those
resulting in maternal toxicity.  At the same dose that resulted in adult
toxicity, offspring growth was decreased during the first four days of
lactation, prior to direct contact with rotenone by the pups.

	4.2.2 Evidence of Neurotoxicity  tc "4.2.2	Evidence of Neurotoxicity "
\l 3

Evidence of neurotoxicity was not observed in available toxicity tests.
In acute lethality studies, clinical signs included tremors,
prostration, labored breathing, and soft feces following oral dosing and
decreased activity, gasping, piloerection, ptosis, and sensitivity to
touch after inhalation exposure.  These clinical signs of toxicity are
likely the result of the known mechanism of action of rotenone, which is
uncoupling of oxidative phosphorylation via blocking electron transport
at complex I within the mitochondria.  No clinical signs of toxicity
were noted in subchronic or chronic studies in dogs, rats, mice, or
hamsters.  Histopathology of the nervous system is not typically
evaluated in these subchronic or chronic studies.

In a special study with rats, continuous intravenous exposure for up to
5 weeks produced behavioral, biochemical, and neuropathological effects
that resemble Parkinson’s disease in humans.  Rotenone administered at
2.5-2.75 mg/kg/day was shown to induce specific neurodegenerative
lesions in nigrostriatal dopaminergic neurons.  The microscopic lesions
progressed over time and correlated with complex I inhibition.  Clinical
signs in affected animals included hypoactivity, unsteady gait, and
hunched posture.  While this route of exposure is not relevant to
humans, it does somewhat mimic inhalation exposure, which is a route of
concern with rotenone.  Except for one LC50 study, no inhalation studies
have been conducted.

	4.2.3 Developmental Toxicity Studies

	<IP_ADDRESS> Developmental Toxicity Study Conclusions

Developmental toxicity studies have been conducted with rotenone in the
rat and mouse.  A study in rabbits has not been submitted.
Developmental toxicity was found in both species at a dose similar to or
greater than that resulting in maternal toxicity.  Rats were
administered 0, 0.75, 1.5, 3, or 6 mg/kg/day by gavage on gestation days
(GDs) 6-19.  Mice were administered 0, 3, 9, 15, or 24 mg/kg/day by
gavage on GDs 6-17.  Maternal toxicity was evident in both species as
decreased body weight gain during the treatment interval at doses of 1.5
mg/kg/day for rats and 24 mg/kg/day for mice.  In addition, rats in all
treated groups had clinical signs of toxicity including salivation and
rubbing of the face and paws on the cage bottom after treatment.

Developmental toxicity was observed at the highest dose tested in both
species.  Fetal body weight was decreased in rats following maternal
administration of 6 mg/kg/day.  In mice, maternal treatment with 24
mg/kg/day resulted in increased resorptions with correspondingly fewer
live fetuses/litter.  No treatment-related structural external,
visceral, or skeletal abnormalities were found in fetuses from treated
dams.

	<IP_ADDRESS> Rotenone - COBS® CD® Rats

In a developmental toxicity study (MRID# 00144294), 25 presumed pregnant
COBS® CD® rats per group were administered 0, 0.75, 1.5, 3, or 6
mg/kg/day of Rotenone (97-98% a.i.; Lot No. not given) by gavage on
gestation days (GD) 6-19, inclusive.  Corn oil was used as the vehicle
and negative control.  On GD 20, all surviving dams were sacrificed and
cesarian sectioned.  All fetuses were weighed, sexed, and examined for
external malformations/variations.  Approximately one-half of the
fetuses were examined for visceral malformation/variations by the Wilson
technique.  The remaining fetuses were processed for skeletal
examination.

Two animals in the 6 mg/kg/day group were found dead, one each on GDs 10
and 17; another dam in this group was sacrificed moribund on GD 18.  One
animal in the 1.5 mg/kg/day group died on GD 11 probably due to a dosing
error.  All remaining animals survived to scheduled termination.
Clinical signs of toxicity were observed in all treated groups and in
the premature decedents of the 6 mg/kg/day group.  The most frequent
observations were salivation and rubbing of face and paws on the bottom
of the cage after treatment which were seen in 11-14, 12-14, 15-22, and
21-24 animals of the 0.75, 1.5, 3, and 6 mg/kg/day groups, respectively.
 At necropsy, eight animals in the 6 mg/kg/day group had stomachs
distended and filled with food.

Maternal body weight gain was significantly decreased for animals
administered 1.5 mg/kg/day compared with the control group.  Weight
change for GDs 0-20 was 95, 94, and 58% of the control level for the
1.5, 3, and 6 mg/kg/day groups, respectively.  Body weight and body
weight gain corrected for gravid uterine weight was also significantly
less than that of the controls for these treated groups.  Lower weight
gain resulted in GD 20 absolute body weight 83% of control for the
high-dose group, although statistical significance was not attained.
Maternal food consumption was not measured.

Therefore, the maternal toxicity LOAEL for rotenone in rats is 0.75
mg/kg/day based on clinical signs of toxicity.  The maternal toxicity
NOAEL is not identified.

At cesarean section, the pregnancy rates, number of corpora lutea,
number of implantations per dam, live fetuses per litter, and fetal sex
ratios were similar between the treated and control groups.  Mean fetal
body weight was significantly less in the 6 mg/kg/day group than that of
the controls.  No dose- or treatment-related external, visceral, or
skeletal malformations/variations were observed in any fetus.

Therefore, the developmental toxicity LOAEL for rotenone in rats is 6
mg/kg/day based on decreased fetal body weight.  The developmental
toxicity NOAEL is 3 mg/kg/day.

This study is classified as Acceptable/Guideline and satisfies the
guideline requirement for a developmental toxicity study [OPPTS 870.3700
(83-3a)] in rats.  This study was conducted prior to implementation of
current guidelines.

	<IP_ADDRESS> Rotenone - CD-1 Mice

In a developmental toxicity study (MRID# 00141407 main, 00145049
range-finding), 30 presumed pregnant CD-1 mice per group were
administered 0, 3, 9, or 15 mg/kg/day of Rotenone (98.2% a.i.; Lot No.
100287) in corn oil by gavage on GDs 6-17, inclusive.  Doses were
selected on the basis of a range-finding study (MRID# 00145049) in which
7 pregnant mice/group were administered up to 24 mg/kg/day.  On GD 18,
all surviving dams were sacrificed and cesarian sectioned.  All fetuses
were weighed, sexed, and examined for external malformations/variations.
 Approximately one-half of the fetuses were examined for visceral
malformation/variations.  The remaining fetuses were eviscerated and
processed for skeletal examination.  In the main study, a total of 26
(278), 23 (268), 24 (271), and 25 (299) litters (fetuses) were examined
in the control, low-, mid-, and high-dose groups, respectively.

Several intercurrent deaths of control and treated animals were
considered incidental to treatment.  No treatment-related clinical signs
of toxicity were observed in any animal.  Maternal body weight and body
weight gain was similar between the treated and control groups.  Food
consumption was not measured and gross necropsy was unremarkable.  In
the range-finding study for animals administered 24 mg/kg/day, maternal
body weight on GD 18 was 90% of the control level and weight gain for GD
0-18 was 59% of the controls.

Therefore, the maternal toxicity LOAEL for rotenone in mice is 24
mg/kg/day based on decreased body weight and body weight gain during
gestation.  The maternal toxicity NOAEL is 15 mg/kg/day.

At cesarean section in the main study, the pregnancy rates, number of
implantations per dam, live fetuses per litter, mean fetal weight, and
fetal sex ratios were similar between the treated and control groups.
The 24 mg/kg/day group of the range-finding study had a greater number
of resorptions per dam as compared with the control group (3.8 vs. 0.5
for the controls) resulting in fewer numbers of live fetuses/litter (8.2
vs. 10.8 for controls).  No dose- or treatment-related external,
visceral, or skeletal malformations/variations were observed in any
fetus.

Therefore, the developmental toxicity LOAEL for rotenone in mice is 24
mg/kg/day based on increased resorptions and the developmental toxicity
NOAEL is 15 mg/kg/day.

This study is classified as Acceptable/Guideline when considered with
the range-finding study and together these satisfy the guideline
requirements for a developmental toxicity study [OPPTS 870.3700
(§83-3a)] in mice.

	4.2.4 Reproductive Toxicity Study

 0.05 or 0.01) than that of controls throughout premating for the
high-dose males and females and occasionally for the mid-dose groups.
Significantly lower body weights for the mid- and high-dose F0 and F1
females continued throughout mating, gestation, and lactation.

At necropsy, organ weight was not affected in the F0 animals.  In the F1
mid- and high-dose groups, organ weight was decreased similar to body
weight.  No treatment-related microscopic lesions were found in the
reproductive organs of parental animals of either generation.  The
parental systemic LOAEL for rotenone in male and female rats was 37.5
ppm (2.4 and 3.0 mg/kg/day for males and females, respectively) based on
decreased body weight and body weight gain.  The parental systemic NOAEL
was 7.5 ppm (0.5 and 0.6 mg/kg/day for males and females, respectively).

 0.05) in the high-dose groups of both generations (9.7-9.9 vs.
11.4-11.8 for the controls).  The reproductive toxicity LOAEL for
rotenone in male and female rats was 75 ppm (4.8 and 6.2 mg/kg/day for
males and females, respectively) based on decreased mean number of live
pups/litter in both generations.  The reproductive toxicity NOAEL was
37.5 ppm (2.4 and 3.0 mg/kg/day for males and females, respectively).

F1 and F2 offspring body weight was slightly or significantly less than
that of controls for the high-dose pups beginning at birth and for the
mid-dose pups beginning on PND 4.  Body weight gain was severely reduced
in the mid- and high-dose pups of both generations throughout lactation
beginning with the interval PND 0-4.  Weight gain at all intervals
during lactation by the mid- and high-dose groups was 72-79% and 43-52%,
respectively, of control for the F1 pups and 74-80% and 41-60%,
respectively, for the F2 pups.  Offspring viability during lactation
days 0-4 was slightly decreased for the high-dose F2 pups (86.1% vs.
98.8% for controls).  The offspring toxicity LOAEL for rotenone in male
and female rats was 37.5 ppm (2.4 and 3.0 mg/kg/day for males and
females, respectively) based on decreased body weight and body weight
gain in both generations.  The offspring toxicity NOAEL was 7.5 ppm (0.5
and 0.6 mg/kg/day for males and females, respectively).

This study is classified as Acceptable/Guideline and does satisfy the
guideline requirement for a reproductive toxicity study [OPPTS 870.3800
(83-4)] in rats.

	4.2.5 Additional Information from Literature Sources

Since the original published study that suggested rotenone as a
dopaminergic neurotoxin and a link to Parkinson’s disease (2000),
hundreds of studies have been published with rotenone as an in vitro and
in vivo model.  A recent literature search on the Entrez PubMed website
and using keywords “rotenone and Parkinson’s Disease” identified
approximately 200 studies related to rotenone as a model for
understanding Parkinson’s disease.

	4.2.6 Pre-and/or Postnatal Toxicity

A literature search identified several studies related to neurotoxicant
exposure during development which may lead to susceptibility to chemical
insult later during adulthood (Melamed et al., 1990; Eriksson et al.,
1993; Eriksson et al., 1996; Gupta et al., 1999; Thiruchelvam et al.,
2002; Barlow et al., 2004).

	<IP_ADDRESS> Determination of Susceptibility  tc "<IP_ADDRESS>	Determination of
Susceptibility " \l 4

No quantitative or qualitative evidence supports increased
susceptibility of rat or mouse fetuses or rat offspring.  Fetuses were
affected from in utero exposure to rotenone in the developmental
toxicity studies at the same dose that resulted in maternal toxicity.
Likewise, post-natal growth and survival were reduced prior to direct
exposure to the test material at the same or higher doses, respectively,
that caused adult systemic toxicity.  Similar doses also resulted in
systemic toxicity in rats following chronic exposure.  In rats, the same
endpoint of toxicity, reduced body weight, was the main effect in
adults, fetuses, and offspring.

It is currently unknown whether in utero exposure to rotenone in the
developing rabbit results in toxicity below or at the same dose
resulting in maternal toxicity.  Likewise, post-natal growth and
survival is unknown for the developing rabbit.

	<IP_ADDRESS>	Degree of Concern Analysis and Residual Uncertainties for Pre-
and/or Post-natal Susceptibility  tc "<IP_ADDRESS>	Degree of Concern Analysis
and Residual Uncertainties for Pre and/or Post-natal Susceptibility " \l
4

A moderate degree of concern exists for protection of infants and
children.  A non-rodent developmental toxicity study is currently not
available.  It is possible that toxicity not observed in the available
rodent developmental toxicity studies would be identified in the
non-rodent developmental toxicity study.  However, in available rat
studies, developmental and offspring toxicity occurred at doses that
also caused parental/adult toxicity; qualitatively the effect in all
ages was the same, i.e., reduced body weight and weight gain.  For the
relevant studies in rats, well defined NOAELs were identified as 3 and
0.6 mg/kg/day for developmental and offspring effects, respectively.  A
NOAEL of 2.0 mg/kg/day was identified in dogs following 6-month
administration.  A long-term study in adult rats has yielded a NOAEL
similar to the dose affecting pup growth, e.g., 0.375 mg/kg/day.

	4.3 Recommendation for a Developmental Neurotoxicity (DNT) Study  tc
"4.3	Recommendation for a Developmental Neurotoxicity (DNT) Study " \l 2

	4.3.1 Evidence that supports requiring a DNT study  tc "4.3.1	Evidence
that supports requiring a DNT study " \l 3

None of the results from the tests conducted to date support the
recommendation for a developmental neurotoxicity study.  However, in a
special study with rats, continuous intravenous exposure for up to 5
weeks produced behavioral, biochemical, and neuropathological effects
that resemble Parkinson’s disease in humans.  Based on these findings,
an inhalation neurotoxicity study is recommended.  The requirement for a
developmental neurotoxicity study is pending until the results from the
inhalation study in adults are available.

	4.3.2 Evidence that supports not requiring a DNT study  tc "4.3.2
Evidence that supports not requiring a DNT study " \l 3

The currently available data on the toxicity of rotenone (via oral
route) do not support the recommendation for a developmental
neurotoxicity study.  Prenatal exposure has not resulted in central
nervous system malformations.  While offspring growth was affected at a
dose which also affected parental animals, no functional or behavioral
changes were reported in adults or pre- and post-weaning pups (complete
neurotoxicity evaluation not done).  Clinical signs suggestive of
neurotoxicity were not observed in any study at doses that caused
systemic toxicity, such as decreased body weight gain.

	4.3.3 Rationale for a Database Uncertainty Factor (UFdb)

No increased offspring sensitivity over parent was observed in the
available rat or mouse pre-natal developmental studies or the post-natal
reproduction study.  However, a data gap does exist for a non-rodent
(rabbit) developmental toxicity study.  In addition, a recent review of
the published literature indicates prenatal exposure to neurotoxicants
(such as maneb and paraquat) may result in selective, permanent
alterations of the nigrostriatal dopaminergic system, which would
enhance susceptibility to chemical exposure later in life (adulthood)
(Barlow et al., 2004).  In essence, the current literature suggests that
exposure to a neurotoxicant during development may produce a biological
system that is more vulnerable to chemical insult later in life (Melamed
et al., 1990; Eriksson et al., 1993; Eriksson, 1996; Gupta et al., 1999;
Thiruchelvam et al., 2002).  A DCI for a subchronic inhalation study
with neurotoxicity parameters was issued due to available literature
indicating Parkinson’s disease in rotenone (intravenous) exposed Lewis
rats.  A DNT study, as well as a subchronic oral neurotoxicity study,
are reserved pending the results of the inhalation neurotoxicity study.
Additional toxicity data gaps remain for a chronic toxicity study in
dogs, dermal penetration study, and a 21-day dermal study.  HED
concluded that an UFdb of 10X is warranted since significant data gaps
exist.

The registrants are no longer supporting agricultural or residential
uses, where the greatest potential for inhalation, dietary, and dermal
exposure could occur.  The potential for inhalation or dermal exposure
by certified applicators using required PPE during the piscicide use is
negligible.  Therefore, the inhalation neurotoxicity study and all other
toxicity data requirements are held in reserve (may be called in later)
pending the outcome of monitoring and further mitigation measures.  The
UFdb will remain in place until data deficiencies are satisfied.

	4.4 Hazard Identification and Toxicity Endpoint Selection  tc "4.4
Hazard Identification and Toxicity Endpoint Selection " \l 2

Based on the registrants’ proposed support of the piscicide use only,
a dietary risk assessment was conducted that estimates acute and chronic
dietary risks resulting from direct applications of rotenone to, or
adjacent to, bodies of water and drinking water consumption.  Dietary
(food) exposure is not expected from the piscicidal use.  Likewise, the
10x factor provided by the Food Quality Protection Act of 1996 does not
apply.

	4.4.1 Acute Reference Dose (aRfD) - Females 13-49 years old  tc "4.4.1
 Acute Reference Dose (aRfD) - Females age 13-49 " \l 3

See section <IP_ADDRESS> for a descriptive summary of the developmental
toxicity study in mice (MRID# 00141407 and 00145049).

Dose and Endpoint for establishing aRfD: The developmental toxicity
NOAEL of 15 mg/kg/day based on increased resorptions at 24 mg/kg/day.

Uncertainty Factor (UF): 1000; includes 10X for interspecies
extrapolation, 10X for intraspecies extrapolation, and 10X for database
uncertainty.

Comments about Study/Endpoint/UF: At the LOAEL, increased resorptions
resulted in fewer numbers of live fetuses/litter.  This effect could
have resulted from one or two exposures during development.  Therefore,
this developmental effect has implications for women of childbearing
age.  Since the effect occurred during development from one or two
exposures, the duration is appropriate for this scenario.  Application
of a 10X UFdb is recommended based on the lack of several studies.

Acute RfD (Females 13-49 years) =	 15 mg/kg/day   =	0.015 mg/kg/day

                                                                   1000

	4.4.2	Acute Reference Dose (aRfD) - General Population  tc "4.4.2	Acute
Reference Dose (aRfD) - General Population " \l 3

A dose and endpoint are not proposed because, based on the available
data, a single dose endpoint was not identified for this population
subgroup.  Clinical signs were reported in rats following a single oral
dose, but a NOAEL could not be identified and a dose-response assessment
could not be made from the data provided.

	4.4.3	Chronic Reference Dose (cRfD)  tc "4.4.3	Chronic Reference Dose
(cRfD) " \l 3

In the chronic/oncogenicity study (MRID# 00156739 and 41657101),
rotenone (>95%, a.i.) was administered in feed to 40 male and 40 female
Charles River Fischer 344 rats per group at concentrations of 0, 7.5,
37.5 or 75 ppm for two years. Based on the standard food factor of 0.05
for rats, dietary concentrations of 7.5, 37.5 and 75 ppm resulted in
doses of 0.375, 1.88 and 3.75 mg/kg/day, respectively.

No significant effect on mortality was noted in the control or treated
groups. Male rats showed no statistically significant difference in body
weight or cumulative weight gain until approximately week 68 in the
mid-dose and high-dose groups, when compared to the controls.  At
termination, males showed a 7% decrease in body weight in the mid-dose
group and a 15% decrease in the high-dose group, compared to the control
group.  Males also exhibited a 10% and 20% decrease in the cumulative
weight gain at week 104 for the mid- and high-dose groups, respectively.
 Females in the mid- and high-dose groups had statistically significant
decreases in body weight throughout the study.  For terminal body
weights, females had decreases of 24% in the mid-dose and 42% in the
high-dose group, compared to control group.  Cumulative weight gain was
also significantly lower between control and treated females ranging
from a 31% decrease in the mid-dose group to a 55% decrease in the
high-dose group.  While no significant difference in food consumption
was noted in the male rats, females in the mid- and high-dose groups
exhibited statistically significant decreases compared to the control
group throughout the study.  This decrease was on average 9% and 21%
less, respectively.

No statistically significant or consistent differences were noted in the
hematological parameters in either the male or female rats in any group.
 Urinalysis results in all rats were unremarkable.  The only clinical
chemistries and organ weights affected in the rats correlated with the
low terminal body weights.  The only macroscopic finding was thinness
reported in 1/40 of the controls, 3/40 of the low-dose, 10/40 of the
mid-dose and 25/40 of the high dose females upon necropsy.

No tumors were found of any treatment-related significance.  The only
non-neoplastic microscopic finding was an increased incidence of
angiectasis and hemorrhage in the adrenals in the high-dose males and
females.  In MRID# 00156739, histopathological exam of the adrenals was
not performed on the low- and mid-dose rats; however, an amendment
providing this additional histopathological information was provided
(MRID# 41657101).  In males, angiectasis was observed in 1/40 in the
control and low-dose groups, 3/39 in the mid-dose group and 13/40 in the
high-dose.  Similar numbers were reported with adrenal hemorrhage: 3/40
controls and low-dose, 3/39 mid-dose and 14/40 in high-dose.  Females
exhibited adrenal angiectasis in 6/40 of controls, 5/40 low-dose, 4/40
mid-dose and 13/40 high-dose.  The incidence in females of adrenal
hemorrhage was 7/40 in controls and low-dose, 10/40 in mid-dose and
14/40 in high-dose.  When the reviewer ran a Fischer Exact test on the
data, results in high-dose male rats were statistically significant,
suggesting the number of adrenal changes were treatment-related;
however, based on the individual microscopic observations, the severity
and distribution of the lesions were not different among any of the
groups, control or treated.  The results were less defined in females
because of a higher number of incidences in the control group, and the
increase in high-dose females was not statistically significant.  As in
males, the severity and distribution of lesions seen in microscopic
observations in females were similar among all groups.

The LOAEL for rotenone is 37.5 ppm (1.88 mg/kg/day), based on decreased
body weight.  The corresponding NOAEL was 7.5 ppm (0.375 mg/kg/day).

At the doses tested, no treatment-related increases in tumor incidences
were observed in male or female rats receiving any dose when compared to
the controls.

Dose and Endpoint for establishing cRfD: Chronic NOAEL of 0.375
mg/kg/day based on

decreased body weight and food consumption in females at 1.88 mg/kg/day.

Uncertainty Factor (UF): 1000; includes 10X for interspecies
extrapolation, 10X for intraspecies extrapolation, and 10X for database
uncertainty.

Comments about Study/Endpoint/UF: The duration of dosing and the
endpoint are appropriate for this scenario.  Application of the UFdb is
required due to the lack of several studies.

Chronic RfD = 0.375 mg/kg/day   =0.004 mg/kg/day

                                                                   1000

	4.4.4 Incidental Oral Exposure (Short- and Intermediate-term)  tc
"4.4.4	Incidental Oral Exposure (Short and Intermediate Term) " \l 3

See Section 4.2.4 for a descriptive summary of the reproductive toxicity
study in rats (MRID# 00141408).

Dose and Endpoint: The parental toxicity NOAEL of 0.5 mg/kg/day based on
decreased body weight and body weight gain at 2.4 and 3.0 mg/kg/day for
males and females, respectively.

Uncertainty Factor (UF): 1000; includes 10x for interspecies
extrapolation, 10X for intraspecies extrapolation, and 10X for database
uncertainty.

Comments about Study/Endpoint:  Reductions in offspring body weight
began as early as PND 4 indicating that the effect began before the pups
had direct contact with the food.  Since the immediate effect on weight
gain between PNDs 0 and 4 suggests that the effect could have been due
to one or two exposures, the duration is appropriate for the short-term
scenario.  Sustained lower weight gain throughout lactation indicates
that the duration is appropriate for the intermediate-term scenario and
included direct exposure to the offspring.

	4.4.5 Dermal Absorption

Little information on the dermal absorption of rotenone is available and
a dermal penetration study has not been submitted.  Two suitable acute
dermal toxicity studies in the rabbit are available for examination.  In
a dermal study with rotenone technical (97% a.i.), rotenone was applied
as a single dose (5 g/kg) as light yellow crystals with no vehicle (not
moistened).  No mortalities or evidence of systemic toxicity were
observed in rabbits at doses up to 5 g/kg (MRID# 43908501).  Slight
erythema is seen at the application site cleared within 24 hours.  These
results suggest negligible dermal absorption of rotenone.  However, if
rotenone was applied with a vehicle there may have been more absorption.
 In the second acute dermal study (MRID# 44336402) with rotenone brittle
extract (rotenone 44.2%, other associated resins 44.2%, inerts 11.6%)
the test material was applied moistened with deionized water (0.952
mL/2020 mg of test material).  There were no deaths with the LD50 >5.0
g/kg for both sexes.  The potential toxicity from repeated dermal
exposure is unknown.

No acute oral toxicity studies exist for rotenone in the rabbit to make
a comparison of oral/dermal toxicity.  Early studies found in the
literature (Haag, 1931; Lehman, 1954; Soloway 1976) contained
oral/dermal toxicity data for the rabbit.  However, these studies had
multiple deficiencies including uncertainties as to purity and
concentration of material tested, vehicle, and duration, and thus, were
not considered.

If the acute oral toxicity study in the rat (MRID# 00145496) is
considered in which the LD50 for male and female rats is 102 mg/kg and
39.5 mg/kg, respectively, and assuming the rabbit is not unusually less
sensitive than the rat, the comparison would indicate that the dermal
absorption of rotenone (as crystals or from a water-wetted suspension)
is less than 100% in the rabbit.

It should be noted that the concentration of rotenone that may be
absorbed dermally under actual conditions will depend on the nature of
the exposure.  More absorption is likely to result from the emulsified
solid than from the dry solid.  However, if a structure activity
relationship (SAR) search is considered, fluazifop-butyl is the compound
most structurally similar to rotenone.  The log P and molecular weight
of fluazifop-butyl are 4.5 and 383.4 respectively.  The log P and
molecular weight of rotenone are 4.1 and 394.4, respectively.  A dermal
absorption study is available in humans for fluazifop-butyl, which
indicated a dermal absorption factor of 9% (HIARC report 2004
fluazifop-butyl, Clark et al., 1993).  Based on relevant physical and
chemical characteristics and dermal information in the human, the
estimated dermal absorption of rotenone in humans is likely 10%.

	4.4.6 Dermal Exposure (Short-, Intermediate- and Long- term)  tc "4.4.6
Dermal Exposure (Short, Intermediate and Long Term) " \l 3

Based on the rationale provided earlier, the dermal absorption of
rotenone is 10% for short-, intermediate-, and long-term scenarios.  See
Section 4.2.4 for a descriptive summary of the

reproductive toxicity study in rats (MRID# 00141408).  Note – no
long-term exposures are expected.

Dose and Endpoint: The parental toxicity NOAEL of 0.5 mg/kg/day based on
decreased body weight and body weight gain at 2.4 and 3.0 mg/kg/day in
males and females, respectively.

Uncertainty Factor (UF):  1000; includes 10X for interspecies
extrapolation, 10X for

intraspecies extrapolation, and 10X for database uncertainty.

Comments about Study/Endpoint/UF:  Because effects from repeated dermal
exposure are unknown, quantitative risk assessment for the short-, and
intermediate-term exposure scenarios is recommended.

	4.4.7 Inhalation Exposure (Short-, Intermediate- and Long-term)  tc
"4.4.7	Inhalation Exposure (Short, Intermediate and Long Term) " \l 3

See Section 4.2.4 and Section 4.4.3 for a descriptive summary of the
two-generation reproduction study in rats and the chronic/oncogenicity
study in rats, respectively.

Study Selected: reproduction study for short- and intermediate- term and
chronic/oncogenicity study for long-term exposure.	 MRID# 00141408 and
00156739, 41657101.  Note - currently, no long-term exposures are
expected.

		Short- and Intermediate-term:

The parental toxicity NOAEL of 0.5 mg/kg/day in rats based on decreased
body weight and body weight gain in adults at 2.4 and 3.0 mg/kg/day M/F
is recommended for short- and intermediate-term inhalation exposure
scenarios.

Long-term:

The chronic oral toxicity NOAEL of 0.375 mg/kg/day in rats based on
decreased body weight and food consumption in females at 1.88 mg/kg/day
is recommended for use in long-term inhalation exposure scenarios.

Comments about Study/Endpoint/UF: Appropriate inhalation toxicity
studies were not available for any exposure scenario.  Reductions in
offspring body weight began as early as PND 4 indicating that the effect
began before the pups had direct contact with the food.  Since the
immediate effect on weight gain between PNDs 0 and 4 suggests that the
effect could have been due to one or two exposures, the duration is
appropriate for the short-term scenario.  Sustained lower weight gain
throughout lactation indicates that the duration is appropriate for the
intermediate-term scenario and included direct exposure to the
offspring.  For long-term inhalation exposure, the chronic toxicity
NOAEL is appropriate for this duration.

	4.4.8 HED’s Level of Concern (LOC)

Summary of HED’s LOCs for risk assessment.  Margins of exposure (MOEs)
that are less than the LOCs are of concern.

TABLE 4.4.8

Route

                                    Duration	Short-term

(1-30 Days)	Intermediate-term

(1 - 6 Months)	 Long-term

(> 6 Months)

Dietary Exposure

Drinking Water	Acute 1000	NA	Chronic 1000

Occupational (Worker) Exposure

Dermal	1000	1000	1000

Inhalation	1000	1000	1000

Residential (Non-Dietary) Exposure

Oral	1000	1000	N/A

Dermal

(All Populations)	1000	1000	1000

Inhalation

(All Populations	1000	1000	1000

For occupational exposure:  This is based on the 10X for interspecies
extrapolation, 10X for intraspecies variation, and an additional 10X for
database uncertainty (1000X).

For residential exposure:  This is based on the 10X for interspecies
extrapolation, 10X for intraspecies variation, and an additional 10X for
database uncertainty (1000X).

	4.4.9 Recommendation for Aggregate Exposure Risk Assessments

In accordance with the Food Quality Protection Act (FQPA) of 1996, for
chemicals having tolerances in food, HED must consider and aggregate
pesticide exposures and risks from three major sources: food, drinking
water, and residential exposures (oral, dermal, and inhalation).   All
uses of rotenone on food crops have been proposed to be cancelled and
thus the requirements of FQPA are not applicable and aggregate risk
assessments have not been conducted.  SEQ CHAPTER \h \r 1

4.4.10 Classification of Carcinogenic Potential

The Science Advisory Panel (SAP) met on September 7, 1988 to review the
weight-of-the-evidence considerations and classification of the
oncogenic potential of rotenone.  The SAP panel endorsed the
classification of rotenone in Group E because of lack of evidence of
carcinogenicity in life-time studies in rats and mice.  The Cancer
Assessment Review Committee (CARC) then met on September 29, 1988 to
examine the review presented by the SAP for rotenone.  The CARC agreed
with the classification recommended by the SAP and classified rotenone
as Group E.

In summary, no evidence of carcinogenicity was seen in mice or rats at
doses that caused systemic toxicity.  Administration of rotenone to both
species for up to two years did not result in an increase in overall
tumor incidence or increase the incidence of any specific type of tumor.
 The chemical was negative for gene mutation in two studies with
Salmonella typhimurium and for mitotic gene conversion with
Saccharomyces cerevisiae.  Micronucleus formation was not induced in the
mouse.  Rotenone did not cause chromosomal aberrations in CHO cells in
vitro with or without activation or in bone marrow cells from rats
administered up to 7 mg/kg orally.  Positive results for gene mutation
were obtained in mouse lymphoma cells without metabolic activation at
concentrations equal to and below those which also caused significant
cytotoxicity.

	<IP_ADDRESS> Carcinogenic Potential in Rats

1.  In a combined chronic/oncogenicity study (MRID# 00156739, 41657101),
rotenone (>95%, a.i.) was administered in feed to 40 male and 40 female
Charles River Fischer 344 rats per group at concentrations of 0, 7.5,
37.5 or 75 ppm for two years.  Based on the standard food factor of 0.05
for rats, dietary concentrations of 7.5, 37.5 and 75 ppm resulted in
doses of 0.375, 1.88 and 3.75 mg/kg/day, respectively.

No significant effect on mortality was noted in the control or treated
groups. Male rats showed no statistically significant difference in body
weight or cumulative weight gain until approximately week 68 in the
mid-dose and high-dose groups when compared to the controls.  At
termination, males showed a 7% decrease in body weight in the mid-dose
group and a 15% decrease in the high-dose group compared to the control
group.  Males also exhibited a 10% and 20% decrease in the cumulative
weight gain at week 104 for the mid- and high-dose groups, respectively.
 Females in the mid- and high-dose groups had statistically significant
decreases in body weight throughout the study.  For terminal body
weights, females had decreases of 24% in the mid-dose and 42% in the
high-dose group compared to control group. Cumulative weight gain was
also significantly lower between control and treated females ranging
from a 31% decrease in the mid-dose group to a 55% decrease in the
high-dose group.  While no significant difference in food consumption
was noted in the male rats, females in the mid- and high-dose groups
exhibited statistically significant decreases compared to the control
group throughout the study. This decrease was on average 9% and 21%
less, respectively.

No statistically significant or consistent differences were noted in the
hematological parameters in either the male or female rats in any group.
Urinalysis results in all rats were unremarkable.  The only clinical
chemistries and organ weights affected in the rats correlated with the
low terminal body weights. The only macroscopic finding was thinness
reported in 1/40 of the controls, 3/40 of the low-dose, 10/40 of the
mid-dose and 25/40 of the high dose females upon necropsy.

No tumors were found of any treatment-related significance.  The only
non-neoplastic microscopic finding was an increased incidence of
angiectasis and hemorrhage in the adrenals in the high-dose males and
females.  In MRID# 00156739, histopathological exam of the adrenals was
not performed on the low- and mid-dose rats; however, an amendment
providing this additional histopathological information was provided
(MRID# 41657101).  In males, angiectasis was observed in 1/40 in the
control and low-dose groups, 3/39 in the mid-dose group and 13/40 in the
high-dose.  Similar numbers were reported with adrenal hemorrhage: 3/40
controls and low-dose, 3/39 mid-dose and 14/40 in high-dose.  Females
exhibited adrenal angiectasis in 6/40 of controls, 5/40 low-dose, 4/40
mid-dose and 13/40 high-dose.  The incidence in females of adrenal
hemorrhage was 7/40 in controls and low-dose, 10/40 in mid-dose and
14/40 in high-dose.  When the reviewer ran a Fischer Exact test on the
data, results in high-dose male rats were statistically significant
suggesting the number of adrenal changes were treatment-related;
however, based on the individual microscopic observations, the severity
and distribution of the lesions were not different among any of the
groups, control or treated.  The results were less defined in females
because of a higher number of incidences in the control group, and the
increase in high-dose females was not statistically significant.  As in
males, the severity and distribution of lesions seen in microscopic
observations in females were similar among all groups.

The LOAEL for rotenone is 37.5 ppm (1.88 mg/kg/day), based on decreased
body weight.  The corresponding NOAEL was 7.5 ppm (0.375 mg/kg/day).

At the doses tested, no treatment-related increases in tumor incidences
were observed in male or female rats receiving any dose when compared to
the controls.

This chronic toxicity/oncogenicity study in the rat is
Acceptable/Guideline with the addition of the amendment providing more
comprehensive histopathological data.

2.  In a carcinogenicity study (MRID# 46274301, 40179801) from the
National Toxicology Program (NTP) rotenone (lot no. 735-RAP-1502, purity
>98% a.i.) was administered in diets at 0, 38, or 75 ppm to 50 F344/N
rats/sex/dose for 103 weeks.  The average daily dose for males and
females in the low dose group was 1.7 and 1.8 mg/kg/day, respectively.

Survival of controls and dosed rats was similar (M: 22/50, 31/50, 30/50
and F: 27/50, 32/50, 31/50 for control, low, high dose, respectively).
Mean body weights of dosed and control male rats were comparable.  Mean
body weights of high dose female rats were 5%-9% lower than control rats
between weeks 58 and 88.

Neoplastic examination revealed parathyroid gland adenomas in 1/41
control, 0/44 low, and 4/44 high dose male rats.  The historical
incidence of this uncommon tumor in untreated control male rats in NTP
studies is 4/1,314 (0.3%).  However, since a tumor was identified in the
control group out of 41 animals, the increased incidence in the high
dose male rats cannot be specifically related to rotenone
administration.

No significant dose-related trend was observed in the incidence of
subcutaneous tissue fibromas, fibrosarcomas, sarcomas, myxosarcomas, or
neurofibrosarcomas in the low dose females.  Statistical significance
(p<0.05) was only attained by combining tumors of differing morphology.
Therefore, the subcutaneous tissue tumors in female rats were not
considered to be chemically related.  The incidences of these tumors in
dosed male rats were not significantly different from that in the
controls.

The LOAEL for rotenone in rats was not established.  The NOAEL is >75
ppm.

This study is classified as Unacceptable/Guideline and satisfies the
guideline requirement for oncogenicity studies [OPPTS 870.4200a] in
rats.

	<IP_ADDRESS> Carcinogenic Potential in Mice

In a carcinogenicity study performed by NTP (MRID# 40179801) rotenone
was administered to 50 male and 50 female B6C3F1 mice (lot no.
735-RAP-1502, purity >98% a.i.) at dietary concentrations of 0, 600 or
1200 ppm for 103 weeks.  The average daily dose for males and females in
the low dose group was 111 and 124 mg/kg/day respectively, and the
average daily dose for males and females in the high dose group was 242
and 265 mg/kg/day, respectively.

The only treatment-related effect noted on mortality was an increase in
survival of the low and high dose male mice compared to the control
group.  The animals surviving the study were 29/50 for control group,
36/50 for 600 ppm group and 47/50 for 1200 ppm group (p<0.001).  No
change in survival occurred in the treated female mice.

Mean body weight was depressed in the male and female mice fed the 600
and 1200 ppm concentrations. Weight was measured weekly through week
eight and monthly thereafter.  The low dose male and female mice did not
show significant differences in weight compared to the control group
until approximately week 37.  At that time, the mean body weight for low
dose males was 6- 12% lower and for low dose females was 12- 20% lower
than controls until the end of the study.  The high dose males and
females also did not show a significant difference in weight until week
37.  Mean weight was then 12-17% below that of the control group in the
high dose males and 17-26% lower in the high dose females.  Final mean
body weight was decreased by 6 and 13% compared to controls for the low
and high dose males and 17 and 24% in low and high dose females.  Body
weight gain was reduced by 12 and 29% compared to the control group in
low and high dose males, and 29 and 40% in low and high dose females,
respectively.  Feed consumption was not decreased in any groups compared
to controls and feed efficiency was not reported.

Histopathological findings at necropsy in the male mice revealed a
significant negative trend for combined hepatocellular adenomas and
carcinomas with dose.  Incidences were 12/47 (26%); 12/49 (24%); and
1/50 (2%) for controls, low- and high-dose groups, respectively.
Fibromas, sarcomas, fibrosarcomas, or neurofibrosarcomas counts were
combined as evidence of subcutaneous tissue tumors and were also
observed in male mice with a negative (p< 0.05) trend with dosing.
Control, low- and high-dose groups had incidences of 8/49 (16%); 4/50
(8%) and 2/50 (4%), respectively.  Historical evidence suggests that
decreased body weight is associated with decreased subcutaneous tumors
in mice.  No significant histopathological changes were observed in the
female mice.

The LOAEL for rotenone is 600 ppm for male and female mice (111 and 124
mg/kg/day, respectively) based on decreased body weight.  The NOAEL was
not determined.

Dosing appeared to be adequate based on the decreased body weight in
both male and female groups and there was not an increase in
treatment-related tumor incidence.

This study is classified as Acceptable/Guideline and satisfies the
guideline requirement for oncogenicity studies [OPPTS 870.4200b] in
mice.

	<IP_ADDRESS> Classification of Carcinogenic Potential

The classification of carcinogenic potential for rotenone is “not
likely to be carcinogenic in humans,” based on the lack of evidence of
carcinogenicity in rats and mice.

Table 4.4.	Summary of Toxicological Doses and Endpoints for Rotenone for
Use in Human Risk Assessments

Exposure

Scenario	Dose Used in Risk Assessment, UF 	Endpoint and Level of Concern
for Risk Assessment	Study and Toxicological Effects

Acute Dietary

(females 13-49)	NOAEL = 15 mg/kg/day

UF = 1000

Acute RfD = 0.015 mg/kg/day	aRFD =

= 0.015 mg/kg/day	Developmental toxicity - mouse

LOAEL = 24 mg/kg/day based on increased resorptions

Acute Dietary

(general population including infants and children)	An appropriate
endpoint attributable to a single dose was not identified in the
available studies, including the developmental toxicity studies.

Chronic Dietary

(all populations)	NOAEL = 0.375 mg/kg/day

UF = 1000

Chronic RfD = 0.0004 mg/kg/day	cRFD =

= 0.0004 mg/kg/day	Chronic/oncogenicity - rat

LOAEL = 1.88 mg/kg/day based on decreased body weight and food
consumption in both males and females

Incidental Oral Short-term

(1 - 30 days)	NOAEL = 0.5 mg/kg/day	Recreational LOC for MOE = 1000
Reproductive toxicity - rat

LOAEL = 2.4/3.0 mg/kg/day [M/F] based on decreased parental (male and
female) body weight and body weight gain

Incidental Oral Intermediate-term

(1 - 6 months)	NOAEL = 0.5 mg/kg/day

	Recreational LOC for MOE = 1000	Reproductive toxicity - rat

LOAEL = 2.4/3.0 mg/kg/day [M/F] based on decreased parental (male and
female) body weight and body weight gain

Dermal

All Durations	NOAEL = 0.5 mg/kg/day

10% dermal absorption factor	Recreational and Occupational LOC

MOE = 1000	Reproductive toxicity - rat

LOAEL = 2.4/3.0 mg/kg/day [M/F] based on decreased parental (male and
female) body weight and body weight gain

Inhalation

Short- and Intermediate-term

(1 - 30 days)	NOAEL = 0.5 mg/kg/day

100% inhalation absorption factor	Recreational and Occupational LOC

MOE = 1000	Reproductive toxicity - rat

LOAEL = 2.4/3.0 mg/kg/day [M/F] based on decreased parental (male and
female) body weight and body weight gain

Inhalation

Long-term

(> 6 months)	NOAEL = 0.375 mg/kg/day

100% inhalation absorption factor	Recreational and Occupational LOC MOE
= 1000	Chronic/oncogenicity - rat

LOAEL = 1.88 mg/kg/day based on decreased body weight and food
consumption in both males and females

Cancer (oral, dermal, inhalation)	Classification: no evidence of
carcinogenicity

UF = uncertainty factor, NOAEL = no observed adverse effect level, LOAEL
= lowest observed adverse effect level, RfD = reference dose (a = acute,
c = chronic), MOE = margin of exposure, LOC = level of concern, NA = Not
Applicable

* Refer to Section 4.1.4

	4.5 Endocrine Disruption

EPA is required under the Federal Food, Drug, and Cosmetic Act (FFDCA),
as amended by the Food Quality Protection Act (FQPA), to develop a
screening program to determine whether certain substances (including all
pesticide active and other ingredients) “may have an effect in humans
that is similar to an effect produced by a naturally occurring estrogen,
or other such endocrine effects as the Administrator may designate.”
Following recommendations of its Endocrine Disruptor and Testing
Advisory Committee (EDSTAC), EPA determined that there was scientific
basis for including, as part of the program, the androgen and thyroid
hormone systems, in addition to the estrogen hormone system.  EPA also
adopted EDSTAC’s recommendation that the Program include evaluations
of potential effects in wildlife.  For pesticide chemicals, EPA will use
FIFRA and, to the extent that effects in wildlife may help determine
whether a substance may have an effect in humans, FFDCA authority to
require the wildlife evaluations.  As the science develops and resources
allow, screening of additional hormone systems may be added to the
Endocrine Disruptor Screening Program (EDSP).

In the available toxicity studies on rotenone, there was no estrogen,
androgen, and/or thyroid mediated toxicity shown.  When additional
appropriate screening and/or testing protocols being considered under
the Agency’s EDSP have been developed, rotenone may be subjected to
further screening and/or testing to better characterize effects related
to endocrine disruption.

5.0 Public Health Data

	5.1 Incident Reports

The following databases were consulted for the poisoning incident data
on the active ingredient rotenone (071003):

1) OPP Incident Data System (IDS) - reports of incidents from various
sources, including registrants, other federal and state health and
environmental agencies and individual consumers, submitted to OPP since
1992.  Reports submitted to the Incident Data System represent anecdotal
reports or allegations only, unless otherwise stated.  Typically no
conclusions can be drawn implicating the pesticide as a cause of any of
the reported health effects.  Nevertheless, sometimes with enough cases
and/or documentation risk mitigation measures may be suggested.

2) Poison Control Centers - as the result of a data purchase by EPA, OPP
received Poison Control Center data covering the years 1993 through 1998
for all pesticides.  Most of the national Poison Control Centers (PCCs)
participate in a national data collection system, the Toxic Exposure
Surveillance System which obtains data from about 65-70 centers at
hospitals and universities.  PCCs provide telephone consultation for
individuals and health care providers on suspected poisonings, involving
drugs, household products, pesticides, etc.

3) California Department of Pesticide Regulation  - California has
collected uniform data on suspected pesticide poisonings since 1982.
Physicians are required, by statute, to report to their local health
officer all occurrences of illness suspected of being related to
exposure to pesticides.  The majority of the incidents involve workers.
Information on exposure (worker activity), type of illness (systemic,
eye, skin, eye/skin and respiratory), likelihood of a causal
relationship, and number of days off work and in the hospital are
provided.

4) National Pesticide Information Center (NPIC) - NPIC is a toll-free
information service supported by OPP.  A ranking of the top 200 active
ingredients for which telephone calls were received during calendar
years 1984-1991, inclusive has been prepared.  The total number of calls
was tabulated for the categories human incidents, animal incidents,
calls for information, and others.

5) National Institute of Occupational Safety and Health’s Sentinel
Event Notification System for Occupational Risks (NIOSH SENSOR) performs
standardized surveillance in seven states from 1998 through 2002.
States included in this reporting system are Arizona, California,
Florida, Louisiana, Michigan, New York, Oregon, Texas, and Washington.
Reporting is very uneven from state to state because of the varying
cooperation from different sources of reporting (e.g., workers
compensation, Poison Control Centers, emergency departments and
hospitals, enforcement investigations, private physicians, etc.).
Therefore, these reports should not be characterized as estimating the
total magnitude of poisoning.  The focus is on occupationlly-related
cases not residential or other non-occupational exposures.  However, the
information collected on each case is standardized and categorized
according to the certainty of the information collected and the severity
of the case.

A c  SEQ CHAPTER \h \r 1 omparison (expressed in percent of cases,)
between rotenone and all other pesticides reported to Poison Control
Centers between 1993-2003 with either symptomatic outcome (SYM),
moderate or more severe outcome (MOD), life-threatening or fatal outcome
(LIFE-TH), seen in a health care facility (HCF), hospitalized (HOSP), or
seen in an intensive care unit (ICU), showed that for occupational
exposure cases, as well as for non-occupational cases involving adults,
older children, and children under six years old, rotenone had a similar
or higher percentage of poisoning incidents reported than other
pesticides (Hawkins 2005).

  SEQ CHAPTER \h \r 1 In general, the most common symptom reported was
eye irritation, which was four times more prevalent than any other
symptom.  Other symptoms reported included dermal irritation, throat
irritation, nausea, and cough/choke.  This supports the finding that
rotenone’s main effect is due to its irritant properties.  Few
neurological symptoms, other than headache and dizziness, were reported,
though there were a few reports of peripheral neuropathy, numbness, or
tremor.

  SEQ CHAPTER \h \r 1 Neither fatalities nor systemic poisonings have
been reported in relation to "ordinary use.”  There were reports of
fatalities from intentional ingestion of rotenone.

	5.2 Other

  SEQ CHAPTER \h \r 1 No scientific literature pertinent to additional
health effects of rotenone in humans was located.

6.0 Exposure Characterization/Assessment

	6.1 Dietary Exposure/Risk Pathway

Food crop uses are no longer being supported by the registrants (see
section 1.0) and are not included in this assessment.  Details of the
dietary assessment may be found in HED’s earlier risk assessment,
ROTENONE: Phase 3 HED Chapter of the Reregistration Eligibility Decision
Document (RED). PC Code: 071003.  DP Barcode: D307385. January 24, 2006.

	6.1.1 Residue Profile  tc "6.1.1	Residue Profile " \l 3

Rotenone
((2R,6aS,12aS)-1,2,6,6a,12,12a-hexahydro-2-isopropenyl-8,9-dimethoxychro
meno [3,4-b]furo[2,3-h]chromen-6-one) is a botanical acaricide,
insecticide, and piscicide.  Rotenone, cube resins other than rotenone,
and derris resins are currently registered for foliar pre-harvest
applications to food/feed crops and are also registered for direct
treatment to livestock, use on lakes, ponds, and reservoirs, and
livestock premises.  However, in memos dated (March 7, 2006; March 17,
2006; and April 5, 2006) the technical registrants (Prentiss, Inc.;
Foreign Domestic Chemicals Corporation; and Tifa Limited) for rotenone
voluntarily cancelled all uses of rotenone except for the piscicidal
uses.

No acceptable studies were submitted by the registrant(s) to support the
nature of the residue guideline requirements; therefore, the nature of
the residue in raw agricultural commodities and animal commodities is
not adequately understood.  Residues of concern could not be adequately
assessed.  Additionally, an acceptable analytical method was not
provided.  These studies and method are no longer needed as all food
uses have been proposed to be cancelled by the rotenone technical
registrants.

An exemption from tolerances was originally granted under 40 CFR
§180.1001 (b) for residues of rotenone
((2R,6aS,12aS)-1,2,6,6a,12,12a-hexahydro-2-isopropenyl-8,9-dimethoxychro
meno [3,4-b]furo[2,3-h]chromen-6-one) in/on raw agricultural
commodities.  The exemption from tolerances is currently listed under 40
CFR §180.905.  As all food uses have been proposed to be cancelled by
the rotenone technical registrants, HED recommends that this exemption
be revoked.

	6.1.2 Acute and Chronic Dietary Exposure and Risk  tc "6.1.2	Acute and
Chronic Dietary Exposure and Risk " \l 3

ted using the Dietary Exposure Evaluation Model (DEEM-FCID™, Version
2.03) which uses food and drinking water consumption data from the
USDA’s Continuing Surveys of Food Intakes by Individuals (CSFII) from
1994-1996 and 1998.  The analysis was performed to support the
reregistration eligibility decision of rotenone.

Dietary risk analyses incorporate both the exposure and toxicity of a
given pesticide.  For acute and chronic analyses, the risk is expressed
as a percentage of a maximum acceptable dose (i.e., the dose which HED
has concluded will result in no unreasonable adverse health effects).
This dose is the Reference Dose (RfD) which is the NOAEL divided by the
sum total of all uncertainty factors.

For acute and non-cancer chronic exposures, HED is concerned when
estimated dietary risk exceeds 100% of the RfD.  References which
discuss the acute and chronic risk assessments in more detail are
available on the EPA/pesticides web site:  “Available Information on
Assessing Exposure from Pesticides, A User’s Guide,” 6/21/2000, web
link:    HYPERLINK
"http://www.epa.gov/fedrgstr/EPA-PEST/2000/July/Day-12/6061.pdf"
http://www.epa.gov/fedrgstr/EPA_PEST/2000/July/Day_12/6061.pdf  ; or see
SOP 99.6 (08/20/99).

	<IP_ADDRESS> Acute Dietary Exposure Results and Characterization

An acute dietary risk assessment (drinking water only) was conducted
using the Dietary Exposure Evaluation Model (DEEM-FCID™), Version
2.03, which uses food and drinking water consumption data from the
United States Department of Agriculture’s (USDA’s) Continuing
Surveys of Food Intakes by Individuals (CSFII) from 1994-1996 and 1998.
The analysis was performed to support the Revised HED Human Health Risk
Assessment for rotenone.

No appropriate acute dietary toxicity endpoint could be identified for
the general population based on the toxicology data currently available
for rotenone.  Therefore, the acute (drinking water only) assessment was
conducted only for the ‘females 13-49 years old’ population
subgroup.

An acute dietary exposure assessment was performed for rotenone
considering exposure from surface water only, as all food uses for this
chemical are no longer supported.  An estimated drinking water
concentration (EDWC) for rotenone surface water provided by the
Environmental Fate and Effects Division (EFED) was used in this
assessment (see section 6.2.2).  The dietary exposure analysis results
in dietary risk estimates that are below the Agency’s level of concern
for acute dietary exposure.  Generally, HED is concerned when risk
estimates exceed 100% of the aRfD.  The exposure for the ‘females
13-49 years old’ population subgroup was 0.009735 mg/kg/day, which
utilized 65% of the acute reference dose (aRfD) at the 95th percentile,
see Table <IP_ADDRESS> below.  It is appropriate to consider the 95th
percentile because the analysis is deterministic and unrefined.

Table <IP_ADDRESS>.  Acute Dietary Exposure and Risk for Rotenone at the 95th
Percentile

Population Subgroup	aRfD

(mg/kg/day)	EDWC

(ppb)	Exposure

(mg/kg/day)	%aRfD

Females 13-49 years old	0.015	200	0.009735	65

	<IP_ADDRESS> Chronic Dietary Exposure Results and Characterization

HED believes the likelihood of chronic drinking water exposure is very
low for most piscicidal applications of rotenone.  However, HED does
feel that the possibility for extended drinking water exposure (from a
few days to a few months) resulting from rotenone piscicide applications
does exist.  This fact along with the lack of any application
temperature restrictions on current rotenone labels, the fact that
rotenone degradation varies greatly depending on water temperature, and
the limited rotenone monitoring data currently available led HED to
produce a drinking water only chronic dietary exposure analysis (see
Table <IP_ADDRESS>).  Using the DWLOC approach, HED determined that chronic
drinking water exposures greater than 40 ppb could pose a potential risk
of concern (> 100% cRfD) to the most highly exposed population
subgroups, infants and children.

Information provided by EFED shows that chronic EDWCs are expected to
exceed 40 ppb for varying numbers of days, depending on the water
temperature and other environmental factors.  Rotenone degradation in 4
to 5oC water was the worst case where HED had actual monitoring data and
under these conditions, rotenone exceeded 40 ppb for 53 days.  Under all
conditions, HED assumed that rotenone could reach drinking water intakes
(within 1 day) and potentially pose risks from consumption of
rotenone-contaminated drinking water.  As a result, of this analysis,
HED believes that 40 ppb is a conservative threshold level for drinking
water exposure when rotenone is applied to bodies of water containing
drinking water intakes.

Table <IP_ADDRESS>

Results of the Drinking Water Only Chronic Dietary Exposure Analysis for
Rotenone

Population Subgroup	cRfD

(mg/kg/day)	Exposure of Concern (ppb)	Number of Days that Exceed
Exposure of Concern

General U.S. Population	0.0004	140

	All Infants (< 1 year old)	0.0004	40

	Children 1-2 years old	0.0004	40

	Children 3-6 years old	0.0004	40	4 in warm water

	53 in cold (4-5o C) water

	27 in Lake Davis, CA

Females 13-49 years old	0.0004	120

		<IP_ADDRESS> Cancer Dietary Exposure Results and Characterization

The classification of carcinogenic potential for rotenone is “not
likely to be carcinogenic in humans,” based on the lack of evidence of
carcinogenicity in rats and mice; therefore, a cancer dietary analysis
was not performed.

	6.2 Water Exposure/Risk Pathway

		6.2.1 Environmental Fate

  SEQ CHAPTER \h \r 1 The fate and transport properties of rotenone in
the environment are not well understood.  In the past, rotenone has been
characterized as immobile and non-persistent.  This characterization is
true only in some circumstances (R. David Jones, 2006).  Rotenone does
degrade rapidly by aqueous photolysis, the photolysis half-life is less
than one day.  Thus degradation would be expected to be rapid on sunny
days in clear water.  Degradation by hydrolysis is also moderately rapid
at 25°C with half-lives of 12.6 days at a pH of 5 and 2 days at a pH of
9.  However, aquatic field studies show that rotenone can persist in
cold water at sufficient concentrations to cause fish mortality for at
least 25 days, even in alkaline conditions.  Rotenone does not appear to
bioaccumulate.

Using Quantitative SAR estimation methods, rotenone does not appear to
be volatile.  Rotenone bonds sufficiently strongly to soils and
sediments that it is unlikely to leach in most circumstances as Kds
range from 4.2 to 122 L kg -1.  Binding is well correlated to specific
surfaces Kss = 0.29 with an R2 of 93%.  Rotenone binding is not well
correlated with organic carbon content alone.  There is expected to be
some propensity to leach in very sandy soils with low organic carbon,
but ground water is unlikely to be affected as hydrolysis occurs too
quickly at all pHs to allow contamination of groundwater to occur except
for the briefest periods. Rotenone should be mobile in runoff to surface
water.

As noted above, there is little information on rotenone degradates.
Rotenolone is known to form by hydrolysis and on bean leaves (available
data), probably by photolysis.  It appears to be more persistent than
the parent rotenone on bean leaves with apparent half-lives of 4 to 5
days.  A few other degradates were identified, but none formed at above
10% of the nominal concentration of rotenone.  Additional data are
needed for potential metabolites of rotenone, particularly for aquatic
sites.

It is worth noting that potassium permanganate, KMnO4, is recommended
(not required) on the labels to ‘detoxify’ rotenone in streams and
rivers downstream of the use site (piscicide use). Recommended
concentrations of KMnO4 are 2 to 4 mg L-1, depending upon stream
conditions and the rotenone concentration.  Labels also note that
rotenone toxicity may continue downstream as far as the water moves in
30 minutes.  Water temperatures less than 50° F can result in longer
times (and distances required for detoxification).  While this advice
appears to be based on a body of practical experience, there are
currently no data to identify the degradation rate of rotenone in the
presence of KMNO4, or how the rate changes with permanganate
concentration.

	6.2.2 Drinking Water Estimates

EFED provided HED with an estimated drinking water concentration (EDWC)
of 200 ppb for surface water (R. David Jones, 2006) based on the
solubility of rotenone in water.  It is also worth noting that the
maximum application rate for the piscicidal use of rotenone (250 ppb)
exceeds the solubility of rotenone. The remaining rotenone above the
solubility limit is likely either suspended or in an emulsion. In either
case, the suspended/emulsified rotenone will be less available for
metabolism or hydrolysis than that in the dissolved phase.

 6.2.3 Monitoring Data and Piscicide Use

Monitoring Data.  There are limited monitoring data for rotenone.  An
aquatic field dissipation study, and data collected in association with
a piscicidal application to Lake Davis in California  are informative
but not useful for quantitative risk assessment purposes (R. David
Jones, 2006).

μg (L-1 from the use in static water bodies, and 50 μg (L-1 in flowing
waters.  In the general directions for the piscicide use of rotenone,
labels state’ “Do not use water treated with rotenone to irrigate
crops or release within ½ mile upstream of a potable water or
irrigation water intake in a standing body of water such as a lake,
pond, or reservoir.”  In addition, in the sections labeled “For Use
in Streams and Rivers” the labels state  “Contact the local water
department to determine if any water intakes are (within one mile) down
flow of the section of stream, river or canal to be treated.  If so,
coordinate with the water department to make sure that the intakes are
closed during treatment and detoxification.”  While it is clear that
these instructions are intended to prevent the contamination of drinking
water with rotenone, it is not clear to what extent they are able to
keep rotenone from reaching the intake of drinking water facilities.  As
noted above, temperature can strongly influence the persistence of
rotenone in water - the half life of rotenone in a 25° C pond was 1.5
days, increased to 10 days at Lake Davis (9° C), and 20 days in a cold
pond (5° C).  Based on the available fate and transport data, it is not
clear that a half-mile restriction around the intake in lakes and
reservoirs would be sufficient to keep rotenone from reaching the
intake, particularly for colder bodies of water such as Lake Davis.
Justification for the efficacy of this restriction has not been
provided.  This is also true for the one-mile buffer for streams and
rivers.  Since the efficacy of permanganate detoxification is not known,
it is not clear that even the one mile restriction would be sufficient
to ensure that drinking water would not be contaminated.  Given that
rotenone can persist for days to weeks in water, rotenone would be
likely to move many miles downstream before degradation and dilution
would result significantly to reduce exposure at drinking water intakes,
particularly if the water is cold.  Also, the dissipation of rotenone in
streams will be dependent upon the flow rate of the water body. While
potassium permanganate treatment may significantly reduce
concentrations, data showing the rate at which this occurs were not
identified for use in this exposure assessment.

6.2.4. Drinking Water Treatment

OPP does not have direct information on the removal of rotenone during
drinking water treatment.  However, hydrolysis of rotenone is relatively
fast under alkaline conditions, about 2 days at pH 9.  Some processes
used to treat drinking water, such as softening may raise the pH as high
as 11 during treatment.  These processes would be expected to
substantially reduce the rotenone concentration, though it is unclear at
this time what degradates might form and what their persistence might
be.  In some cases, strong ultraviolet light is used for disinfection.
Because rotenone is so susceptible to aqueous photolysis, this treatment
may also be expected to substantially reduce rotenone parent
concentration present in the source water.  However, because neither of
these processes can currently be quantified in the context of drinking
water treatment of rotenone, nor can the locations where these processes
are used be identified, it is not possible at this time to assess how
they might reduce rotenone in drinking water quantitatively. Softening
is used only where water is high in calcium and magnesium.  UV treatment
is considered an advanced treatment technique and has yet to be widely
adopted as a practice in the United States.