[Federal Register Volume 84, Number 142 (Wednesday, July 24, 2019)]
[Rules and Regulations]
[Pages 35555-35568]
[FR Doc No: 2019-15649]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[EPA-HQ-OPP-2007-1005; FRL-9997-06]

Chlorpyrifos; Final Order Denying Objections to March 2017
Petition Denial Order

AGENCY: Environmental Protection Agency (EPA).

ACTION: Order.

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SUMMARY: In this Order, EPA denies the objections to EPA's March 29,
2017 order denying a 2007 petition from the Pesticide Action Network
North America (PANNA) and the Natural Resources Defense Council (NRDC)
to revoke all tolerances and cancel all registrations for the
insecticide chlorpyrifos. This order is issued under section
408(g)(2)(C) of the Federal Food, Drug, and Cosmetic Act (FFDCA) and
constitutes final agency action on the 2007 petition. The objections
were filed by Earthjustice on behalf of 12 public interest groups, the
North Coast Rivers Alliance, and the States of New York, Washington,
California, Massachusetts, Maine, Maryland, and Vermont.

DATES: This Order is effective July 24, 2019.

ADDRESSES: The docket for this action, identified by docket
identification (ID) number EPA-HQ-OPP-2007-1005, is available at http://www.regulations.gov or at the Office of Pesticide Programs Regulatory
Public Docket (OPP Docket) in the Environmental Protection Agency
Docket Center (EPA/DC), West William Jefferson Clinton Bldg., Rm. 3334,
1301 Constitution Ave. NW, Washington, DC 20460-0001. The Public
Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through
Friday, excluding legal holidays. The telephone number for the Public
Reading Room is<PHONE_NUMBER>, and the telephone number for the OPP
Docket is<PHONE_NUMBER>. Please review the visitor instructions and
additional information about the docket available at http://www.epa.gov/dockets.

FOR FURTHER INFORMATION CONTACT: Pesticide Re-Evaluation Division
(7508P), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Ave. NW, Washington, DC 20460-0001; telephone number:
(703) 347-0206; email address<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this action apply to me?

    In this document, EPA denies all objections in response to a March
29, 2017 order denying the 2007 PANNA and NRDC petition requesting that
EPA revoke all tolerances and cancel all pesticide product
registrations for chlorpyrifos. In addition to the Petitioners, this
action may be of interest to agricultural producers, food manufacturers
or pesticide manufacturers, and others interested in food safety issues
generally. The following list of North American Industrial
Classification System (NAICS) codes is not intended to be exhaustive,
but rather provides a guide to help readers determine whether this
document applies to them. Potentially affected entities may include:
     Crop production (NAICS code 111), e.g., agricultural
workers; greenhouse, nursery, and floriculture workers; farmers.
     Animal production (NAICS code 112), e.g., cattle ranchers
and farmers, dairy cattle farmers, livestock farmers.
     Food manufacturing (NAICS code 311), e.g., agricultural
workers; farmers;

greenhouse, nursery, and floriculture workers; ranchers; pesticide
applicators.
     Pesticide manufacturing (NAICS code 32532), e.g.,
agricultural workers; commercial applicators; farmers, greenhouse,
nursery, and floriculture workers; residential users.

B. What action is the agency taking?

    In this order, EPA denies objections to EPA's order of March 29,
2017 (the Denial Order), in which EPA denied a 2007 petition (the
Petition) from PANNA and NRDC (the Petitioners) that requested that EPA
revoke all tolerances for the pesticide chlorpyrifos established under
FFDCA section 408. (Ref. 1) The Petition also sought the cancellation
of all chlorpyrifos pesticide product registrations under section 6 the
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), 7 U.S.C.
136d.
    The Petition raised the following claims regarding both EPA's 2006
FIFRA reregistration decision and active registrations of chlorpyrifos
in support of the request for tolerance revocations and product
cancellations:
    1. EPA has ignored genetic evidence of vulnerable populations.
    2. EPA has needlessly delayed a decision regarding endocrine
disrupting effects.
    3. EPA has ignored data regarding cancer risks.
    4. EPA's 2006 cumulative risk assessment (CRA) for the
organophosphates misrepresented risks and failed to apply FQPA 10X
safety factor. (Note: For convenience's sake, the legal requirements
regarding the additional safety margin for infants and children in
FFDCA section 408(b)(2)(C) are referred to throughout this response as
the ``FQPA 10X safety factor'' or simply the ``FQPA safety factor.''
Due to Congress' focus on both pre- and post-natal toxicity, EPA has
interpreted this additional safety factor as pertaining to risks to
infants and children that arise due to pre-natal exposure as well as to
exposure during childhood years.)
    5. EPA has over-relied on registrant data.
    6. EPA has failed to properly address the exporting hazard in
foreign countries from chlorpyrifos.
    7. EPA has failed to quantitatively incorporate data demonstrating
long-lasting effects from early life exposure to chlorpyrifos in
children.
    8. EPA has disregarded data demonstrating that there is no evidence
of a safe level of exposure during pre-birth and early life stages.
    9. EPA has failed to cite or quantitatively incorporate studies and
clinical reports suggesting potential adverse effects below 10%
cholinesterase inhibition.
    10. EPA has failed to incorporate inhalation routes of exposure.
    EPA's Denial Order denied the Petition in full (82 FR 16581). Prior
to issuing that order, EPA provided the Petitioners with two interim
responses on July 16, 2012 and July 15, 2014. The July 16, 2012
response denied claim 6 (export hazard) completely, and that portion of
the response was a final agency action. The remainder of the July 16,
2012 response and the July 15, 2014 response expressed EPA's intention
to deny six other petition claims (1-5 and 10). (Note: In the 2012
response, EPA did, however, inform Petitioners of its approval of label
mitigation (in the form of rate reductions and spray drift buffers) to
reduce bystander risks, including risks from inhalation exposure, which
in effect partially granted Petition claim 10.) EPA made clear in both
the 2012 and 2014 responses that, absent a request from Petitioners,
EPA's denial of those six claims would not be made final until EPA
finalized its response to the entire Petition. Petitioners made no such
request, and EPA therefore finalized its response to those claims in
the Denial Order.
    The remaining Petition claims (7-9) all related to same issue:
Whether the potential exists for chlorpyrifos to cause
neurodevelopmental effects in children at exposure levels below EPA's
existing regulatory standard (10% cholinesterase inhibition). Because
these claims raised novel, highly complex scientific issues, EPA
originally decided it would be appropriate to address these issues in
connection with the registration review of chlorpyrifos under FIFRA
section 3(g) and decided to expedite that review, intending to finalize
it several years in advance of the October 1, 2022 registration review
deadline. EPA decided as a policy matter that it would address the
Petition claims raising these matters on a similar timeframe. Although
EPA had expedited its registration review to address these issues, the
Petitioners were not satisfied with EPA's progress in responding to the
Petition, and they brought legal action in the Ninth Circuit Court of
Appeals to compel EPA to either issue an order denying the Petition or
to grant the Petition by initiating the tolerance revocation process.
Following several rounds of litigation (see discussion of the
litigation in Unit III. of this Order), EPA was ordered by the Ninth
Circuit to issue either a tolerance revocation rule or an order denying
the Petition by March 31, 2017. In re Pesticide Action Network of North
America v. EPA, 840 F.3d (9th Cir. 2016). Accordingly, in compliance
with the court's order, the Denial Order also finalized EPA's response
on claims 7-9. As to those claims, EPA concluded that, despite several
years of study, the science addressing neurodevelopmental effects
remains unresolved and that further evaluation of the science during
the remaining time for completion of registration review was warranted
regarding whether the potential exists for adverse neurodevelopmental
effects to occur from current human exposures to chlorpyrifos. EPA
therefore denied the remaining Petition claims, concluding that it was
not required to complete--and would not complete--the human health
portion of the registration review or any associated tolerance
revocation of chlorpyrifos without resolution of those issues during
the ongoing FIFRA registration review of chlorpyrifos.
    In June 2017, several public interest groups and states filed
objections to the Denial Order pursuant to the procedures in FFDCA
section 408(g)(2). Specifically, Earthjustice submitted objections on
behalf of the following 12 public interest groups: Petitioners PANNA
and NRDC, United Farm Workers, California Rural Legal Assistance
Foundation, Farmworker Association of Florida, Farmworker Justice,
GreenLatinos, Labor Council for Latin American Advancement, League of
United Latin American Citizens, Learning Disabilities Association of
America, National Hispanic Medical Association and Pineros y Campesinos
Unidos del Noroeste. Another public interest group, the North Coast
River Alliance, submitted separate objections. With respect to the
states, New York, Washington, California, Massachusetts, Maine,
Maryland, and Vermont submitted a joint set of objections (Ref. 2).
    The objections focus on three main topics: (1) The Objectors assert
that the FFDCA requires EPA apply to the FFDCA safety standard in
reviewing any petition to revoke tolerances and that EPA's decision to
deny the Petition failed to apply that standard; (2) The Objectors
contend that the record before EPA demonstrates that chlorpyrifos
results in unsafe drinking water exposures and adverse
neurodevelopmental effects and that EPA must therefore issue a final
rule revoking all chlorpyrifos tolerances; and (3) The Objectors claim
that EPA committed procedural error in failing to respond to comments,
and they specifically point to comments related to neurodevelopmental
effects, inhalation risk, and Dow AgroSciences'

physiologically based pharmacokinetic model (PBPK model) used in EPA's
risk assessment. Dow AgroSciences, which is now Corteva AgriScience,
will be referred to as Corteva throughout the remainder of this Order.
    On June 5, 2017, the same the day the Objectors were required to
submit their objections to EPA, the League of United Latin American
Citizens (LULAC) and the other 11 public interest Objectors represented
by Earthjustice filed suit in the U.S. Court of Appeals for the 9th
Circuit directly challenging the Denial Order, asserting that the court
could review the order directly, even in the absence of EPA's final
order under FFDCA section 408(g)(2)(C) responding to the objections
they had just submitted. LULAC, et al. v. Wheeler, et al., No. 17-
71636. In their pleadings, Petitioners alternatively asked the court to
issue a mandamus order compelling EPA to respond to the June 2017
objections within 60 days. On August 9, 2018, a three-judge panel of
the 9th Circuit vacated the Denial Order and ordered EPA to revoke all
chlorpyrifos tolerances and cancel all chlorpyrifos registrations
within 60 days. Id., 899 F.3d 814. EPA sought rehearing of that
decision before an en banc panel of the 9th Circuit, a request that was
granted on February 6, 2019, effectively vacating the August 9, 2018
panel decision. On April 19, 2019, the en banc panel granted the
request for mandamus and directed EPA to respond to the objections not
later than 90 days from that date. The court did not otherwise address
the claims in the case.
    After reviewing the objections, EPA has determined that the
objections related to Petition claims regarding neurodevelopmental
toxicity must be denied because the objections and the underlying
Petition are not supported by valid, complete, and reliable evidence
sufficient to meet the Petitioners' burden under the FFDCA, as set
forth in EPA's implementing regulations. Further, for reasons stated in
the Denial Order, EPA has concluded that it is also appropriate to deny
the objections related to new issues raised after EPA's 2006 tolerance
reassessment and reregistration of chlorpyrifos. These issues are being
addressed according to the schedule for EPA's ongoing registration
review of chlorpyrifos. EPA is also denying all claims related to
drinking water risk and the use of the Corteva PBPK model in EPA's 2014
risk assessment and 2015 proposed rule because these claims were not
made in the Petition and the objections process cannot be used to raise
new issues and restart the petition process. Finally, EPA is denying
the objections claiming procedural error, as EPA is not required to
respond to comments made during the rulemaking process in this
adjudication denying petition objections. Any response to comments will
be completed in connection with EPA's final action in registration
review.

C. What is the Agency's authority for taking this action?

    The procedure for filing objections to EPA's final rule or order
issued under FFDCA section 408(d) and EPA's authority for acting on
such objections is contained in FFDCA section 408(g) (21 U.S.C.
346a(g)) and EPA's regulations at 40 CFR part 178.

II. Statutory and Regulatory Background

    In this unit, EPA provides background on the relevant statutes and
regulations governing the objections as well as on pertinent Agency
policies and practices.

A. FFDCA and FIFRA Standards

    EPA establishes maximum residue limits, or ``tolerances,'' for
pesticide residues in food and feed commodities under FFDCA section
408. Without a tolerance or an exemption from the requirement of a
tolerance, food containing a pesticide residue is ``adulterated'' under
FFDCA section 402 and may not be legally moved in interstate commerce.
FFDCA section 408 was substantially rewritten by the Food Quality
Protection Act of 1996 (FQPA) (Pub. L. 104- 170, 110 Stat. 1489
(1996)), which established a detailed safety standard for pesticides
and integrated EPA's regulation of pesticide food residues under the
FFDCA with EPA's registration and re-evaluation of pesticides under
FIFRA. The standard to establish, leave in effect, modify, or revoke a
tolerance is stated in FFDCA section 408(b)(2)(A)(i). ``The
Administrator may establish or leave in effect a tolerance for a
pesticide chemical residue in or on a food only if the Administrator
determines that the tolerance is safe.'' Id. ``The Administrator shall
modify or revoke a tolerance if the Administrator determines it is not
safe.'' Id. ``Safe'' is defined by FFDCA section 408(b)(2)(A)(ii) to
mean that ``there is a reasonable certainty that no harm will result
from aggregate exposure to the pesticide chemical residue, including
all anticipated dietary exposures and all other exposures for which
there is reliable information.'' Among the factors that must be
addressed in making a safety determination, FFDCA section 408(b)(2)(D)
directs EPA to consider ``validity, completeness, and reliability of
the available data from studies of the pesticide chemical and pesticide
chemical residue.''
    Risks to infants and children are given special consideration.
Specifically, FFDCA section 408(b)(2)(C)(i)(II) requires that EPA
assess the risk of pesticides based on ``available information
concerning the special susceptibility of infants and children to the
pesticide chemical residues, including neurological differences between
infants and children and adults, and effects of in utero exposure to
pesticide chemicals . . . .'' (21 U.S.C. 346a(b)(2)(C)(i)(II)). This
provision also creates a presumption that EPA will use an additional
safety factor for the protection of infants and children. Specifically,
it directs that ``[i]n the case of threshold effects, . . . an
additional tenfold margin of safety for the pesticide chemical residue
and other sources of exposure shall be applied for infants and children
to take into account potential pre- and post-natal toxicity and
completeness of the data with respect to exposure and toxicity to
infants and children.'' (21 U.S.C. 346a(b)(2)(C)). EPA is permitted to
``use a different margin of safety for the pesticide chemical residue
only if, on the basis of reliable data, such margin will be safe for
infants and children.'' Id.
    While the FFDCA authorizes the establishment of legal limits for
pesticide residues in food, FIFRA section 3(a) requires the approval of
pesticides prior to their sale and distribution and establishes a
registration regime for regulating the use of pesticides. FIFRA
regulates pesticide use in conjunction with its registration scheme by
requiring EPA review and approval of pesticide labels and specifying
that use of a pesticide inconsistent with its label is a violation of
federal law. In the FQPA, Congress integrated action under the two
statutes by requiring that the safety standard under the FFDCA be used
as a criterion in FIFRA registration actions for pesticide uses that
result in residues in or on food, (see FIFRA section 2(bb)), and
directing that EPA coordinate, to the extent practicable, revocations
of tolerances with pesticide cancellations under FIFRA. (see FFDCA
section 408(l)(1)). FIFRA section 4 directed EPA to determine whether
pesticides first registered prior to 1984 should be reregistered,
including whether any associated FFDCA tolerances are safe and should
be left in effect (see FIFRA section 4(g)(2)(E)). FFDCA section 408(q)
directed EPA to complete that tolerance reassessment (which included
the reassessment of all chlorpyrifos tolerances) by 2006. Following the

completion of FIFRA reregistration and tolerance reassessment, FIFRA
section 3(g) requires EPA to re-evaluate pesticides under the FIFRA
standard--which includes a determination whether to leave in effect
existing FFDCA tolerances--every 15 years under a program known as
``registration review.'' The deadline for completing the current
registration review for chlorpyrifos is October 1, 2022.

B. Procedures for Establishing, Modifying, or Revoking Tolerances

    Tolerances are established, modified, or revoked by rulemaking
under the unique procedural framework set forth in the FFDCA.
Generally, a tolerance rulemaking is initiated by the party seeking to
establish, modify, or revoke a tolerance by means of filing a petition
with EPA. (See FFDCA section 408(d)(1)). EPA publishes in the Federal
Register a notice of the petition filing and requests public comment.
After reviewing the petition and submitted comments, FFDCA section
408(d)(4) provides that EPA may issue a final rule establishing,
modifying, or revoking the tolerance; issue a proposed rule to do the
same; or issue an order denying the petition.
    Once EPA takes action granting or denying the petition, FFDCA
section 408(g)(2) allows any party to file objections with EPA and seek
an evidentiary hearing on those objections. Objections and hearing
requests must be filed within 60 days after the date on which EPA
issues its rule or order under FFDCA section 408(d). A party may not
raise issues in objections unless they were part of the petition and an
objecting party must state objections to the EPA decision and not just
repeat the allegations in its petition. Corn Growers v. EPA, 613 F.3d
266 (D.C. Cir. 2010), cert. denied, 131 S. Ct. 2931 (2011). EPA's final
order on the objections, issued under FFDCA section 408(g)(2)(C), is
subject to judicial review. (21 U.S.C. 346a(h)(1)).

III. Chlorpyrifos Regulatory Background

    Chlorpyrifos (0,0-diethyl-0-3,5,6-trichloro-2-pyridyl
phosphorothioate) is a broad-spectrum, chlorinated organophosphate (OP)
insecticide that has been registered for use in the United States since
1965. By pounds of active ingredient, it is the most widely used
conventional insecticide in the country. Currently registered use sites
include a large variety of food crops (e.g., tree fruits and nuts; many
types of small fruits and vegetables, including vegetable seed
treatments; grain/oilseed crops; cotton), and non-food use settings
(e.g., ornamental and agricultural seed production; non-residential
turf; industrial sites/rights of way; greenhouse and nursery
production; sod farms; pulpwood production; public health; and wood
protection). For some of these crops, chlorpyrifos is currently the
only cost-effective choice for control of certain insect pests. In
2000, the chlorpyrifos registrants reached an agreement with EPA to
voluntarily cancel all residential use products except those registered
for ant and roach baits in child-resistant packaging and fire ant mound
treatments (e.g., 65 FR 76233 (Dec. 6, 2000); 66 FR 47481 (Sept. 12,
2001).
    The OPs are a group of closely related pesticides that affect
functioning of the nervous system. The OPs were included in the
Agency's first priority group of pesticides to be reviewed under FQPA.
In 2006, EPA completed FIFRA section 4 reregistration and FFDCA
tolerance reassessment for chlorpyrifos and the OP class of pesticides
and determined those tolerances were safe and should be left in effect
(Ref. 3). Having completed reregistration and tolerance reassessment,
EPA is required to complete the next re-evaluation of chlorpyrifos
under the FIFRA section 3(g) registration review program by October 1,
2022. Given ongoing scientific developments in the study of the OPs
generally, in March 2009 EPA announced its decision to prioritize the
FIFRA section 3(g) registration review of chlorpyrifos by opening a
public docket and releasing a preliminary work plan to complete the
chlorpyrifos registration review by 2015--7 years in advance of the
date required by law.
    The registration review of chlorpyrifos has proven to be far more
complex than originally anticipated. The OPs presented EPA with
numerous novel scientific issues that the agency has taken to multiple
FIFRA Scientific Advisory Panel (SAP) meetings since the completion of
reregistration in 2006. (Note: The SAP is a federal advisory committee
created by FIFRA section 25(d) and serves as EPA's primary source of
peer review for significant regulatory and policy matters involving
pesticides.) Many of these complex scientific issues formed the basis
of the 2007 petition filed by PANNA and NRDC, specifically issues
related to potential human health risks associated with volatilization
and neurodevelopmental effects. During the registration review process,
EPA reviews the currently available body of scientific data, including
animal and epidemiology data, and the assessment of potential risks
from various routes of exposure. Therefore, when EPA began the
registration review for chlorpyrifos in March 2009, the Agency
indicated that the Agency had decided to address the Petition on a
similar timeframe to EPA's expedited registration review schedule.
    Although EPA has expedited the chlorpyrifos registration review to
address the novel scientific issues raised by the Petition in advance
of the statutory deadline, the complexity of the issues has precluded
EPA from finishing this review according to the Agency's original
timeframe. The Petitioners were dissatisfied with the pace of EPA's
response efforts and sued EPA in federal court on three separate
occasions to compel a faster response to the Petition. As explained in
Unit I. of this Order, EPA addressed 7 of the 10 claims asserted in the
Petition by either denying the claim, issuing a preliminary denial or
approving label mitigation to address the claims, but notwithstanding
these efforts, on August 10, 2015, the court issued a mandamus order
directing EPA to ``issue either a proposed or final revocation rule or
a full and final response to the administrative Petition by October 31,
2015.'' In re Pesticide Action Network of North America v. EPA, 798
F.3d (9th Cir. 2015).
    In response to that order, EPA issued a proposed rule to revoke all
chlorpyrifos tolerances on October 30, 2015 (published in the Federal
Register on November 6, 2015 (80 FR 69080)), based on its unfinished
registration review risk assessment. EPA acknowledged it had
insufficient time to complete its drinking water assessment and its
review of data addressing the potential for neurodevelopmental effects.
    On December 10, 2015, the Ninth Circuit issued a further order
requiring EPA to complete any final rule (or petition denial) and fully
respond to the Petition by December 30, 2016. On June 30, 2016, EPA
sought a six-month extension to that deadline in order to allow EPA to
fully consider the most recent views of the FIFRA SAP with respect to
chlorpyrifos toxicology. The FIFRA SAP report was finalized and made
available for EPA consideration on July 20, 2016 (Ref. 4). On August
12, 2016, the court rejected EPA's request for an extension and ordered
EPA to complete its final action by March 31, 2017 (effectively
granting EPA a three-month extension). On November 17, 2016, EPA
published a notice of data availability (NODA) seeking public comment
on both EPA's revised risk and water assessments and reopening the
comment period on the proposal to revoke all chlorpyrifos tolerances
(81 FR

81049). The comment period for the NODA closed on January 17, 2017.
    Following the close of the comment period on the NODA, EPA issued
the Denial Order on March 29, 2017, as described in Unit I. of this
Order. As noted, in June 2017, EPA received objections to the Denial
Order from both public interest groups and states, and some of those
same organizations simultaneously filed suit in the Ninth Circuit
seeking to challenge the Denial Order in advance of EPA's response to
the submitted objections. That litigation is summarized in Unit I. of
this Order.

IV. The Petition and EPA's Petition Response

    As explained in Unit I. of this Order, PANNA and NRDC submitted the
Petition in 2007, raising 10 claims in support of their request that
EPA revoke all chlorpyrifos tolerances under the FFDCA and cancel all
chlorpyrifos registrations under FIFRA. EPA's Denial Order denied the
Petition in full. The following is a summary of EPA's response in the
Denial Order to the 10 Petition claims.

A. Claim 1: Genetic Evidence of Vulnerable Populations

    The Petitioners claimed that as part of EPA's 2006 reregistration
and tolerance reassessment decision the Agency failed to calculate an
appropriate intra-species uncertainty factor (i.e., within human
variability) for chlorpyrifos in both its aggregate and cumulative risk
assessments (CRA). They asserted that certain data (the ``Furlong
study'') addressing intra-species variability in the behavior of the
detoxifying enzyme paraoxonase (PON1), indicates that the Agency should
have applied an intra-species safety factor ``of at least 150X in the
aggregate and cumulative assessments'' rather than the 10X factor EPA
applied.
    In the Denial Order, EPA explained that it carefully considered the
issue of PON1 variability and determined that data addressing PON1 in
isolation are not appropriate for use alone in deriving an intra-
species uncertainty factor and that the issue is more appropriately
handled using a PBPK model. Further, the derivation of an intra-species
factor of over 150X advocated by the Petitioners is based on combining
values from humanized mice with human measured values with a range from
highest to lowest; the Furlong study derivation is inappropriate and
inconsistent with international risk assessment practice. In addition,
the 2008 FIFRA SAP did not support the PON1 data used in isolation.
Finally, Petitioners' statement that the Furlong study supports an
intra-species uncertainty factor of at least 150X likely overstates
potential variability. EPA therefore denied this aspect of the
Petition.

B. Claim 2: Endocrine Disrupting Effects

    Petitioners summarized a number of studies evaluating the effects
of chlorpyrifos on the endocrine system, asserting that, taken
together, the studies ``suggest that chlorpyrifos may be an endocrine
disrupting chemical, capable of interfering with multiple hormones
controlling reproduction and neurodevelopment.''
    EPA denied this claim because the Petition did not explain whether
and how endocrine effects should form the basis of a decision to revoke
tolerances. The basis for seeking revocation of a tolerance is a
showing that the pesticide is not ``safe.'' Petitioners neither
asserted that EPA should revoke tolerances because effects on the
endocrine system render the tolerances unsafe, nor did Petitioners
submit a factual analysis demonstrating that aggregate exposure to
chlorpyrifos presents an unsafe risk to humans based on effects on the
endocrine system.
    EPA noted that while the cited studies provide qualitative
information that exposure to chlorpyrifos may be associated with
effects on the androgen and thyroid hormonal pathways, these data alone
do not demonstrate that current human exposures from existing
tolerances are unsafe. Further, EPA explained that in June 2015, it
completed an Endocrine Disruption Screening Program weight-of-evidence
conclusion for chlorpyrifos. That analysis evaluated all observed
effects induced, the magnitude and pattern of responses observed across
studies, taxa, and sexes, and the Agency also considered the conditions
under which effects occurred, in particular whether or not endocrine-
related responses occurred at dose(s) that also resulted in general
systemic or overt toxicity. The Agency concluded that, based on weight-
of-evidence considerations, further testing was not recommended for
chlorpyrifos since there was no evidence of potential interaction with
the estrogen, androgen, and thyroid pathways.

C. Claim 3: Cancer Risks

    Petitioners claim that the Agency ``ignored'' a December 2004
National Institutes of Health Agricultural Health Study showing that
the incidence of lung cancer has a statistically significant
association with chlorpyrifos exposure. Petitioners did not otherwise
explain whether and how these data support the revocation of tolerances
or the cancellation of pesticide registrations. Specifically,
Petitioners did not present any fact-based argument demonstrating that
aggregate exposure to chlorpyrifos poses an unsafe carcinogenic risk.
Accordingly, EPA denied the Petition to revoke chlorpyrifos tolerances
or cancel chlorpyrifos registrations to the extent the Petition relies
on claims pertaining to carcinogenicity. EPA went on to note, however,
that while there is initial suggestive epidemiological evidence of an
association between chlorpyrifos and lung cancer, it is reasonable to
conclude chlorpyrifos is not a carcinogen in view of the lack of
carcinogenicity in the rodent bioassays and the lack of a genotoxic or
mutagenic potential.

D. Claim 4: CRA Misrepresents Risks, Failed To Apply FQPA 10X Safety
Factor

    Petitioners asserted that EPA relied on limited data and inaccurate
interpretations of a specific study (the ``Zheng study'') to support
its decision to remove the FQPA safety factor in the 2006 OP cumulative
risk assessment (CRA). Petitioners claimed the Zheng study showed an
obvious difference between juvenile and adult responses to chlorpyrifos
that supported retention of the 10X safety factor for chlorpyrifos in
the CRA. EPA concluded that Petitioners' assertions did not provide a
sufficient basis for revoking chlorpyrifos tolerances. The Petitioners'
claim that the data EPA relied upon support a different FQPA safety
factor for chlorpyrifos in the CRA did not amount to a showing that
chlorpyrifos tolerances are unsafe as Petitioners did not present a
factual analysis demonstrating that the lack of a 10X safety factor in
the CRA for chlorpyrifos poses unsafe cumulative exposures to the OPs.
For this reason, EPA denied the Petitioners' request to revoke
chlorpyrifos tolerances or cancel chlorpyrifos registrations on the
basis of the FQPA safety factor in the CRA.
    Despite the inadequacy of Petitioners' FQPA CRA safety factor
claims, EPA nonetheless examined the evidence Petitioners cited
regarding the Zheng study. EPA acknowledged that in that study, pups
appeared to be more sensitive than adults at the tested high dose.
However, at the low-dose end of the response curve, relevant for human
exposures, little to no difference was observed. This result is
consistent with a comparative cholinesterase study submitted by Corteva
that specifically compared the dose-response relationship in juvenile
and adult rats and found no basis for concluding that juveniles are
more sensitive, further

supporting EPA's use of an FQPA safety factor of 1X for the AChE
inhibition endpoint used in the 2006 OP CRA.

E. Claim 5: Over-Reliance on Registrant Data

    Petitioners asserted that in reregistering chlorpyrifos EPA
``cherry picked'' data, ``ignoring robust, peer-reviewed data in favor
of weak, industry-sponsored data to determine that chlorpyrifos could
be re-registered and food tolerances be retained.'' As such,
Petitioners argued that the Agency's reassessment decision is not
scientifically defensible. EPA concluded that this Petition claim was
not purported to be an independent basis for revoking chlorpyrifos
tolerances or cancelling chlorpyrifos registrations but simply support
for Petitioners' arguments in other parts of the Petition. While
Petitioners claim that EPA ignored robust, peer-reviewed data in favor
of weak, industry-sponsored data for the reregistration of
chlorpyrifos, Petitioners did not cite to any studies other than those
used to support their other claims. In general, Petitioners did not
provide any studies in the Petition that EPA failed to evaluate. Since
the specific studies cited by Petitioners were not associated with this
claim, but rather their other claims, EPA's response to the specific
studies were, therefore, addressed in its responses to Petitioners'
other claims. EPA went on to explain, however, that the Agency does not
ignore robust, peer-reviewed data in favor of industry-sponsored data
and that EPA has a public and well-documented set of procedures that it
applies to the use and significance of all data utilized to inform risk
management decisions. EPA does rely on registrant-generated data
submitted in response to FIFRA and FFDCA requirements, as these data
are conducted and evaluated in accordance with a series of
internationally harmonized and scientifically peer-reviewed study
protocols designed to maintain a high standard of scientific quality
and reproducibility. But EPA does not end its review there. To further
inform the Agency's risk assessment, EPA is committed to the
consideration of other sources of information such as data identified
in the open, peer-reviewed literature and information submitted by the
public as part of the regulatory evaluation of a pesticide.

F. Claim 6: EPA Failed to Properly Address the Exporting Hazard in
Foreign Countries From Chlorpyrifos

    In the July 16, 2012 interim Petition response, EPA issued a final
denial of this claim, as it was not a claim subject to the FFDCA, which
provides for an administrative objections process following the denial
of a petition. EPA explained in the interim response that it lacked
authority to address the risks chlorpyrifos may pose to workers in
foreign countries who may not utilize worker protection equipment that
the United States requires. Further, EPA noted that it has no authority
to ban the export of pesticides to foreign countries regardless of
whether those pesticides may be lawfully used in the United States.
Accordingly, EPA denied this claim, and that denial constituted final
agency action.

G. Claims 7-9: EPA Failed to Quantitatively Incorporate Data
Demonstrating Long-Lasting Effects From Early Life Exposure to
Chlorpyrifos in Children; EPA Disregarded Data Demonstrating That There
Is no Evidence of a Safe Level of Exposure During Pre-Birth and Early
Life Stages; and EPA Failed To Cite or Quantitatively Incorporate
Studies and Clinical Reports Suggesting Potential Adverse Effects Below
10% Cholinesterase Inhibition.

    The Petitioners asserted that human epidemiology and rodent
developmental neurotoxicity data suggest that pre-natal and early life
exposure to chlorpyrifos can result in long-lasting, possibly permanent
damage to the nervous system and that these effects are likely
occurring at exposure levels below 10% cholinesterase inhibition, EPA's
existing regulatory standard for chlorpyrifos and other OPs. They
assert that EPA has therefore used the wrong endpoint as a basis for
regulation and that, taking into account the full spectrum of toxicity,
chlorpyrifos does not meet the FFDCA safety standard or the FIFRA
standard for registration.
    EPA grouped these claims together because they fundamentally all
raised the same issue: Whether the potential exists for chlorpyrifos to
cause neurodevelopmental effects in infants and children from exposures
(either to mothers during pregnancy or directly to infants and
children) that are lower than those resulting in 10% cholinesterase
inhibition--the basis for EPA's long-standing point of departure (POD)
in regulating chlorpyrifos and other OPs. EPA noted that these claims
were not challenges to EPA's 2006 reregistration decision for
chlorpyrifos, but rather, new challenges to EPA's ongoing approval of
chlorpyrifos under FIFRA and the FFDCA because they rely in large
measure on data published after EPA completed both its 2001
chlorpyrifos Interim Reregistration Decision and the 2006 OP CRA that
concluded the reregistration process for chlorpyrifos and all other
OPs. As matters that largely came to light after the completion of
reregistration, EPA made clear that these Petition issues are being
addressed as part of the registration review of chlorpyrifos--the next
round of re-evaluation under FIFRA section 3(g). The Denial Order noted
that the question of OP neurodevelopmental toxicity was, and remains,
an issue at the cutting edge of science, involving significant
uncertainties.
    During registration review, EPA conducted an in-depth analysis of
the available OP and chlorpyrifos biomonitoring data and of the
available epidemiologic studies from three major children's health
cohort studies in the U.S., specifically from the Columbia Center for
Children's Environmental Health (CCCEH), Center for the Health
Assessment of Mothers and Children of Salinas (CHAMACOS), and Mt.
Sinai. EPA three times, in 2008, 2012, and 2016 has presented
approaches and proposals to the FIFRA SAP for evaluating this
epidemiologic data exploring the possible connection between in utero
and early childhood exposure to chlorpyrifos and adverse
neurodevelopmental effects. The SAP's reports have rendered numerous
recommendations for additional study and sometimes conflicting advice
for how EPA should consider (or not consider) the epidemiology data in
conducting EPA's registration review human health risk assessment for
chlorpyrifos and served to underscore that the science on this question
is not resolved and would benefit from additional inquiry. Indeed, EPA
explained in the Denial Order that the comments received by EPA
indicate that there are considerable areas of uncertainty with regard
to what the epidemiology data show and deep disagreement over how those
data should be considered in EPA's risk assessment. In August 2016, the
Ninth Circuit made clear, however, that EPA was to provide a final
response to the Petition by March 31, 2017, and that no more extensions
would be granted--regardless of whether the science remains unsettled
and irrespective of whatever options may exist for resolution of these
issues during the registration review process.
    While EPA acknowledged its obligation to respond to the Petition as
required by the court, EPA noted that the court's order did not and
could not compel EPA to complete the registration review of
chlorpyrifos and the issues required for that determination in advance
of the October 1, 2022 deadline

provided in FIFRA section 3(g), 7 U.S.C. 136a(g). Although past EPA
Administrators had proposed to attempt to complete that review several
years in advance of the statutory deadline (and respond to the Petition
on the same time frame), it was not possible to fully address these
registration issues earlier than the registration review period. As a
result, EPA concluded that it needed to adjust the schedule for
chlorpyrifos so that it could complete its review of the science
addressing neurodevelopmental effects prior to making a final
registration review decision whether to retain, limit, or remove
chlorpyrifos from the market. Accordingly, EPA denied the Petition
claims and stated its intention to complete a full and appropriate
review of the neurodevelopmental data before either finalizing the
proposed rule of October 30, 2015, or taking an alternative regulatory
path.
    EPA explained that that denial of the Petition on these grounds
provided was consistent with governing law because the petition
provision in FFDCA section 408(d) does not address the timing for
responding to a petition, nor does it limit the extent to which EPA may
coordinate or stage its petition responses with the registration review
provisions of FIFRA section 3(g). Provided EPA completes registration
review by October 1, 2022, Congress otherwise gave the EPA
Administrator the discretion under FIFRA to determine the schedule and
timing for completing the review of the over 1000 pesticide active
ingredients currently subject to evaluation under FIFRA section 3(g).
EPA may lawfully re-prioritize the registration review schedule
developed by earlier administrations provided that decision is
consistent with law and an appropriate exercise of discretion. See
Federal Communications Commission v. Fox Television Stations, 129 S.Ct.
1800 (2009) (Administrative Procedure Act does not require that a
policy change be justified by reasons more substantial than those
required to adopt a policy in the first instance). Nothing in FIFRA
section 3(g) precludes EPA from altering a previously established
registration review schedule. Given the absence of a clear statutory
directive, FIFRA and the FFDCA provide EPA with discretion to take into
account EPA's registration review of a pesticide in determining how and
when the Agency responds to FFDCA petitions to revoke tolerances. As
outlined previously, given the importance of this matter and the fact
that critical questions remained regarding the significance of the data
addressing neurodevelopmental effects, EPA asserted that there is good
reason to extend the registration review of chlorpyrifos and therefore
to deny the Petition. To find otherwise would effectively give
petitioners under the FFDCA the authority to re-order scheduling
decisions regarding the FIFRA registration review process that Congress
has vested in the Administrator.

H. Claim 10: Inhalation Exposure From Volatilization

    Petitioners assert that when EPA completed its 2006 OP CRA, EPA
failed to consider and incorporate significant exposures to
chlorpyrifos-contaminated air that exist for some populations in
communities where chlorpyrifos is applied. Petitioners assert that
these exposures exceeded safe levels when considering cholinesterase
inhibition as a POD and that developmental neurotoxicity may occur at
even lower exposure levels than those resulting in cholinesterase
inhibition.
    To the extent Petitioners are asserting that human exposure to
chlorpyrifos spray drift and volatilized chlorpyrifos present
neurodevelopmental risks for infants and children, EPA denied this
claim for the reasons stated in EPA's response to claims 7-9.
    With respect to Petitioners' claim that exposures to spray drift
and volatilized chlorpyrifos present a risk from cholinesterase
inhibition, EPA denied the Petition for the reasons identified in EPA's
Spray Drift Mitigation Decision of July 16, 2012, and EPA's interim
response of July 15, 2014, addressing chlorpyrifos volatilization.
Specifically, in the Spray Drift Mitigation Decision, EPA determined
that the chlorpyrifos registrants' adoption of label mitigation (in the
form of label use rate reductions and no-spray buffer zones) eliminated
risk from cholinesterase inhibition as a result of spray drift. As for
risks presented by volatilized chlorpyrifos that may occur following
application, EPA's July 15, 2014 interim response to the Petition
explained that vapor-phase inhalation studies for both chlorpyrifos and
chlorpyrifos-oxon made clear that neither vapor-phase chlorpyrifos nor
chlorpyrifos oxon presents a risk of cholinesterase inhibition.

V. Objections

    The three separate sets of objections to the Denial Order filed
with EPA in June 2017 raise similar concerns and can be reduced to the
following three primary arguments:
     The Objectors argue that EPA's Denial Order applied the
wrong legal standard. (Note: All persons filing objections will be
referred to as ``Objectors.'') They assert that neither ``scientific
uncertainty'' nor the October 2022 deadline for registration review
under FIFRA section 3(g), nor the widespread agricultural use of
chlorpyrifos, provide a basis for denying petitions to revoke. They
claim that EPA has unlawfully left chlorpyrifos tolerances in place
without making the safety finding required by the FFDCA.
     The Objectors assert that EPA has previously found that
chlorpyrifos tolerances are unsafe and has not disavowed those
findings. Specifically, they claim that EPA has found that chlorpyrifos
results in unsafe drinking water exposures and results in adverse
neurodevelopmental effects to children and that EPA must therefore
revoke the tolerances.
     The Objectors argue that EPA's Denial Order committed a
procedural error by failing to address significant concerns raised in
the comments on EPA's 2014 risk assessment and 2015 proposed revocation
that EPA's assessment fails to protect children. In particular, the
Objectors focus on concerns raised in comments asserting that (1) EPA's
use of 10% cholinesterase as a regulatory standard is not protective
for effects to children's developing brains; (2) EPA has not properly
accounted for effects from inhalation of chlorpyrifos from spray drift
and volatilization; and (3) EPA inappropriately used the Corteva PBPK
model to reduce inter- and intra-species safety factors because the
model is ethically and scientifically deficient.

VI. Corteva's Comments on the Objections

    Corteva, the primary registrant of chlorpyrifos products registered
for use in agriculture, submitted a response to the objections on
August 27, 2018, raising specific detailed scientific concerns with the
objections (Ref. 4). In addition, Corteva states that there is nothing
in the FFDCA suggesting that statute requires EPA to make a safety
finding in order to deny a response to a petition and that the FFDCA's
implementing regulations place the burden on a petitioner to prove that
a pesticide is unsafe. Corteva argues that to find otherwise would lead
to the result that EPA is required to renew its safety finding every
time a petition is filed, irrespective of the strength and quality of
the evidence cited and regardless of whether EPA is engaged in an
ongoing scientific review of issues addressed in the petition through
FIFRA registration review.

VII. EPA's Response to Objections

    EPA's responses to the specific objections summarized in Unit V.
are provided in this unit.

A. Claims Regarding the Legal Standard for Reviewing Petitions To
Revoke

    Before addressing the specific legal objections, EPA notes that the
Objectors' concerns focus primarily on EPA's denial of Petition claims
7-10 as they relate to the potential for adverse neurodevelopmental
effects to children from exposure to chlorpyrifos in food, drinking
water, and from spray drift. These concerns fundamentally relate to
issues EPA is evaluating in its current registration review of
chlorpyrifos. EPA is in the process of completing revised risk
assessments to address new data and advancements in risk assessment
methodology since EPA's 2006 safety finding for chlorpyrifos as part of
FIFRA section 4 reregistration and FFDCA section 408(q) tolerance
reassessment to review tolerances for pesticide residues in effect
(Ref. 3). The Objectors have not materially challenged EPA's denial of
Petition claims that related to matters before EPA at the time of EPA's
2006 safety finding. Specifically, they have not raised objections to
the denial of claims relating to the genetic evidence for human
vulnerability with respect to the detoxifying enzyme paraoxonase,
endocrine-related effects, or carcinogenicity (claims 1-3). Nor have
Objectors challenged most aspects of EPA's conclusions in the Denial
Order respecting the potential for current chlorpyrifos exposures to
result in acetyl cholinesterase inhibition--the regulatory POD used in
EPA's 2006 reregistration and tolerance reassessment decisions.
    In sum, the objections are focused on EPA's ongoing work in FIFRA
registration review to evaluate more recent information addressing the
risk of adverse neurodevelopmental effects. With respect to these
claims, EPA has concluded, after many years of attempting to obtain
information necessary to validate this information, that the objections
and the underlying petition fail to provide evidence of
neurodevelopmental effects that is sufficiently valid, complete, and
reliable at this time to meet the burden petitioners for revocation
bear in presenting a case that tolerances are unsafe, pursuant to the
standard under FFDCA section 408(b)(2). In addition, as provided in the
Denial Order, EPA has concluded that it is also appropriate to deny the
petition to allow EPA to complete its assessment of the potential for
adverse neurodevelopmental outcomes in connection with the ongoing
chlorpyrifos FIFRA registration review.
    1. Burden of coming forward with valid, complete, and reliable
evidence. In response to the Objectors' claims that EPA applied an
incorrect legal standard in denying the Petition, EPA disagrees that
the FFDCA requires EPA to make a new safety determination in response
to every petition to revoke under FFDCA section 408(d) or that it must
revoke tolerances in the absence of making a renewed safety
determination in response to a petition. Petitioners cite the FFDCA
safety definition and the findings EPA must make to establish a
tolerance or leave a tolerance in effect when reassessing the safety of
tolerance under FFDCA section 408(q) and FIFRA section 3(g). None of
their arguments, however, specifically focus on the FFDCA section
408(d) petition process to modify or revoke a tolerance and EPA's
implementing procedural regulations that require persons seeking
tolerance revocation to come forward with evidence sufficient to
support a finding that the applicable safety standard has not been met.
In other words, even if one were to assume, arguendo, that the same
safety standard applies to EPA action on a petition to revoke a
tolerance as applies to the Agency's initial establishment of a
tolerance, that is a separate issue from the evidentiary burden a
petitioner must meet to support its position. As explained in this
unit, in this case, EPA reasonably construes the FFDCA and the Agency's
implementing regulations to require petitioners seeking withdrawal of a
tolerance to support this request with valid, complete and reliable
data that set forth why the tolerances are unsafe, a burden Petitioners
here have failed to meet.
    By way of background, it is important to note that while Congress
addressed the requirements for petitions to establish a tolerance with
considerable specificity, see FFDCA section 408(d)(2)(A), it by
contrast expressly left the specific requirements for petitions to
modify or revoke a tolerance to EPA's rulemaking discretion. Id., FFDCA
section 408(d)(2)(B). In turn, EPA's long-standing regulations require
petitions seeking modification or revocation of a tolerance based on
``new data'' to furnish that data in the same form required for
petitions seeking to establish tolerances, to the extent applicable. 40
CFR 180.32(b) (``New data should be furnished in the form specified in
180.7(b) [pertaining to ``[p]etitions proposing tolerances''] for
submitting petitions, as applicable.''). Thus, Congress expressly
conferred discretion on EPA to specify the requirements for withdrawal
of an existing tolerance, and EPA's long-standing regulations require a
petitioner seeking revocation to meet the same standard of data
reliability as a petitioner seeking to establish a tolerance.
    FFDCA section 408(b)(2)(D)(i) requires that all actions of the
Administrator to establish, modify, leave in effect, or revoke
tolerances must consider, among other factors, ``the validity,
completeness, and reliability of the available data from studies of the
pesticide chemical and pesticide chemical residue.'' Consistent with
this obligation, EPA regulations provide that a petitioner has a burden
to provide ``reasonable grounds'' for revocation, including an
assertion of facts to justify the modification or revocation of the
tolerance (40 CFR 180.32(b)). Further, the regulations also make clear
that persons seeking revocation have an initial evidentiary burden that
must be met before the question of whether the applicable safety
standard under FFDCA section 408(b)(2) is met is properly placed before
EPA. See 40 CFR 179.91 (Party requesting revocation hearing has initial
burden of going forward with evidence). This longstanding
interpretation of the statute and the procedures Congress established
is permissible and entitled to substantial deference. Sebelius v.
Auburn Reg'l Med. Ctr., 133 S. Ct. 817, 826-827 (2013) (citing National
Cable & Telecomm. Ass'n v. Brand X internet Servs., 545 U.S. 967, 980
(2005)). Notably, this regulation mirrors EPA's implementing FIFRA
hearing regulations at 40 CFR 164.80(a), which likewise make clear that
a person seeking cancellation or suspension must present the case that
the standards for those actions have been met.
    Recently, in Ellis v. Housenger, 252 F. Supp. 3d 800, 809 (N.D.
Cal. 2017), the U.S. District for the Northern District of California
interpreted those regulations, explaining that the FIFRA hearing
regulations place the burden on the proponent of a regulatory action to
present an affirmative case for action, and that initial burden is
properly applied to petitions seeking immediate action. Similarly,
before the question whether the applicable safety standard under FFDCA
section 408(b)(2) is met is properly placed before the EPA, petitioners
must first meet their burden of coming forward with sufficient evidence
to show that pesticide tolerances to be modified or revoked are not
safe.
    EPA concludes that Petitioners have not met that burden.
Petitioners have

not presented evidence to establish that chlorpyrifos tolerances must
be revoked because of the risk of neurodevelopmental effects at levels
lower than EPA's currently regulatory standard. After several years and
numerous, significant efforts to evaluate the petition claims related
to neurodevelopmental toxicity, including communications with study
authors and researchers in an effort to obtain underlying data and
validate and replicate reported results, EPA concludes that the
information yet presented by Petitioners is not sufficiently valid,
complete, and reliable to support abandoning the use of AChE inhibition
as the critical effect for regulatory purposes under the FFDCA section
408.
    Cholinesterase inhibition and the cholinergic effects (i.e., the
physiological or behavioral changes) caused by organophosphorous
pesticides, including chlorpyrifos, have long been the endpoints that
EPA and nearly every other pesticide regulatory body in the world have
used in assessing potential human health hazards. EPA has regarded data
showing cholinesterase inhibition in brain, red blood cell (RBC), or
plasma, and data on physiological or behavioral changes as critical
effects for regulatory purposes. Guideline animal toxicity studies have
historically been used in support of the 10% RBC acetylcholinesterase
(AChE) inhibition point of departure (POD) for chlorpyrifos in EPA risk
assessments.
    EPA's 2006 Registration Eligibility Decision (RED) for chlorpyrifos
relied on AChE inhibition results from laboratory animals for deriving
the POD. Although not acknowledged by the Petitioners and Objectors, in
conducting risk assessments in support of the chlorpyrifos RED, EPA
also considered the emerging new information from laboratory studies
that identified potential concern for increased sensitivity and
susceptibility for the young from neurodevelopmental effects unrelated
to AChE inhibition. At that time, EPA did not believe those studies
support a neurodevelopmental POD for quantitative risk assessment, but
it did provide the support for EPA's retention of the FQPA 10X factor
in the 2001 chlorpyrifos IRED (Ref. 5).
    While Petitioners and Objectors are correct that EPA did not retain
the FQPA 10X for chlorpyrifos in the OPs 2006 cumulative risk
assessment, that assessment dealt only with the established common
mechanism of toxicity for the OPs--AChE inhibition--not with potential
hazards that relate to the OPs individually. Accordingly, EPA did not
reduce the 10X safety factor as it relates to chlorpyrifos specifically
in its 2006 tolerance reassessment and reregistration determination
that chlorpyrifos tolerances are safe. To the extent the Objectors are
therefore arguing that EPA must, at a minimum, retain the FQPA 10X
factor for chlorpyrifos because of the potential for neurodevelopmental
effects, those objections are denied as moot. EPA's most recent
assessment of the chlorpyrifos tolerances that was challenged in the
Petition did retain the FQPA 10X, in part because of neurodevelopmental
studies.
    The Petition and the objections also argue, however, that EPA
should not simply retain the FQPA 10X safety factor but should revoke
chlorpyrifos tolerances because of evidence showing the potential for
neurodevelopmental effects to occur well below EPA's existing
regulatory standard. In sum, they believe EPA should be using the
results of existing epidemiologic data to set a regulatory POD for
chlorpyrifos at levels that would require EPA to revoke all
chlorpyrifos tolerances.
    EPA has, since the issuance of the 2006 RED, consistently concluded
that the available data support a conclusion of increased sensitivity
of the young to the neurotoxic effects of chlorpyrifos and for the
susceptibility of the developing brain to chlorpyrifos. This conclusion
comes from an evaluation across multiples lines of evidence including
mechanistic studies and newer in vivo laboratory animal studies, but
particularly with the available epidemiology reports along with
feedback from the 2012 and 2016 FIFRA SAP meetings. As noted, EPA has
retained the FQPA 10X safety factor on these grounds. However, EPA and
the FIFRA SAP have also consistently cited the lack of robustness of
these data for deriving a POD for neurodevelopmental effects given (1)
the absence of a clear mechanism of action for chlorpyrifos in the
developing brain; (2) the dosing regimen in in vivo studies that
differs from internationally accepted protocols; and (3) the lack of
any meaningful raw data from the epidemiologic data that are the
centerpiece of this area of inquiry.
    The lack of a mechanistic understanding for effects on the
developing brain precludes EPA from validly or reliably assessing
potential differences (and similarities) between laboratory animals and
humans with respect to dose-response and temporal windows of
susceptibility. In the absence of this information, EPA has no valid or
reliable ways to bridge the scientific interpretation of the laboratory
studies and epidemiology studies with chlorpyrifos. In addition, the
dosing regimen used in the in vivo studies means the data are not
sufficiently valid, complete and reliable for regulatory purposes given
the problems they present for the quantitative interpretation and
extrapolation of the results. Specifically, the in vivo laboratory
animal studies generally use fewer days of dosing that are aimed at
specific periods of rodent fetal or early post-natal development
compared to internationally adopted guideline studies which are
intended to cover both pre- and post-gestational periods. The degree to
which these shorter dosing periods coincide with comparable windows of
susceptibility in human brain development is unclear. In addition,
except for some studies conducted recently, most of the in vivo
laboratory studies use doses that are higher than doses that cause 10%
RBC AChE inhibition. These studies are therefore are not useful
quantitatively to evaluate whether EPA's current regulatory standard is
or is not sufficient to preclude the potential for neurodevelopmental
effects.
    Finally, and most significantly, despite numerous requests over the
last decade, the authors of the epidemiologic studies that provide
potentially the most relevant information regarding effects to humans
have never provided the underlying data from their studies to EPA to
allow EPA and others to independently verify the validity and
reliability of the results reported in their published articles. EPA
believes it is necessary to first replicate the statistical analyses
used in the studies to ensure their accuracy. In addition, EPA wants to
examine the raw data used in the analysis to ensure appropriate
handling of data points and in potentially conducting alternative
statistical analyses. For example, EPA would want to evaluate the
elimination of certain study participants from the CCCEH study that
were deemed to be outliers in order to determine whether their
exclusion was proper and how it may have affected the results. The lack
of publicly available raw data does not necessarily preclude EPA from
reliance on such information for the purpose of risk assessment. Given
the long history and internationally harmonized use of
acetylcholinesterase inhibition as the point of departure for
chlorpyrifos, however, EPA reasonably requires more complete
information regarding the studies in the published articles to
establish a POD and that threshold has not been met in this instance.
Due to these limitations, EPA does not believe the Petition, or the
objections make the

case for EPA to establish a POD based on neurodevelopmental effects,
which remains central to the Petitioners' claims 7-9.
    EPA understands that this conclusion is at odds with its revised
risk assessment that it published for comment with the NODA in November
2016. By way of explanation, EPA notes that it has undertaken
considerable efforts to assess the available chlorpyrifos data,
including the references cited by the Petitioners in support for their
claims related to neurodevelopmental effects. Specifically, in Chapter
4 and Appendices 2-4 of the 2014 human health risk assessment, EPA
provides a detailed discussion of the strengths and uncertainties
associated with the epidemiology studies. For example, although the
studies used US-based exposure profiles in real world situations, EPA
noted that the lack of data on the timing of chlorpyrifos applications
was a key concern in the exposure assessment. EPA conducted a
preliminary review of available literature and research on epidemiology
in mothers and children following exposures chlorpyrifos and other OPs,
laboratory studies on animal behavior and cognition, AChE inhibition,
and mechanisms of action, and took it to the SAP in 2008.
    The CCCEH study used concentrations of pesticides (including
chlorpyrifos) in umbilical cord blood as a measure of exposure, while
two other birth cohorts used urinary biomarkers in the mothers to
estimate pesticide exposure. In 2012, the EPA convened another meeting
of the FIFRA SAP to review the latest experimental data related to AChE
inhibition, cholinergic and non-cholinergic adverse outcomes, including
neurodevelopmental studies on behavior and cognition effects. The EPA
also performed an in-depth analysis of the available chlorpyrifos
biomonitoring data and of the available epidemiologic studies from
three major children's health cohort studies in the U.S., including
those from the CCCEH, Mt. Sinai, and CHAMACOS. The EPA explored
plausible hypotheses on mode of actions/adverse outcome pathways (MOAs/
AOPs) leading to neurodevelopmental outcomes seen in the biomonitoring
and epidemiology studies.
    EPA convened another meeting of the FIFRA SAP in April 2016, which
was unique in focus compared to the previous meetings in that EPA
explicitly proposed using information directly from the CCCEH published
articles for deriving the POD. The 2016 SAP did not support the
``direct use'' of the cord blood and working memory data for deriving
the regulatory endpoint for several reasons, among them, the lack of
raw data from the epidemiology study (Ref. 4).
    This feedback is consistent with concerns raised in public comments
EPA received on the use of the epidemiology data throughout the course
of registration review from the grower community, pesticide
registrants, and the U.S. Department of Agriculture. The final FIFRA
SAP report provides a detailed account of the concerns associated with
the Agency's April 2016 proposed approach to selecting the point of
departure (POD) and its use in quantitative risk assessment.
Specifically, the SAP report noted that ``[t] he majority of the panel
stated that using cord concentrations for derivation of the POD could
not be justified by any sound scientific evaluation. The Panel was
conflicted with respect to the importance of a 2% change in working
memory.'' Id. at 19. The Panel went on to note that ``the Agency's
inability to confidently estimate previous exposure patterns and/or
intensity hinders the use of cord blood at delivery as an anchor from
which to extrapolate back to a more toxicologically meaningful internal
exposure metric.'' Id. at 42. The SAP also noted the insufficient
information about timing of chlorpyrifos applications in relation to
cord blood concentrations at the time of birth, as well as
uncertainties about the prenatal window(s) of exposure linked to
reported effects.
    EPA acknowledges that the 2012 and 2016 SAPs note effects in the
epidemiology and experimental studies below 10% AChE inhibition. In
addition, both the 2008 and 2012 SAP commented on the strengths of the
CCCEH epidemiologic studies and the value of the information they
provide. However, despite these strengths, both the 2008 and 2012
Panels recommended that AChE inhibition remain as the source of data
for the PODs. The 2016 SAP expressed significant reservations about the
proposed approach to use the cord blood as the source of data for the
POD. It noted the incompleteness of the information, including the lack
of raw data, reproducibility of analytical blood data, and knowledge
about chlorpyrifos application timing relative to pregnancy. EPA has
evaluated the SAP's concerns, as well as public comments received on
the 2016 updated human health risk assessment echoed a number of the
SAP's concern regarding use of the CCCEH study. Based on the
uncertainties identified by the 2016 SAP, the published articles from
CCCEH are not complete for deriving a POD. EPA acknowledges this
conclusion differs from the position supported in the 2016 revised
human health risk assessment, but EPA believes the shortcomings of the
data identified raise issues of validity, completeness and reliability
under the FFDCA that direct against using the data for risk assessment
at this time. As stated in the Denial Order, EPA intends to continue
its exploration of the uncertainty around using neurodevelopmental
effects to establish a POD as it works to complete registration review,
including renewed efforts to obtain the raw data from the epidemiologic
studies that are the central to consideration of potential
neurodevelopmental effects.
    Notably, EPA has made requests to CCCEH, CHAMACOS, and Mt. Sinai to
obtain the raw data, and visited Columbia University in an attempt to
better understand their study results and what raw data exist. EPA also
requested the original CCCEH study protocol to determine whether its
specific questions regarding exposure timing could be addressed with
the raw data. EPA was informed the CCCEH protocol was not available,
and EPA did not receive the raw data from any of those research
institutions. Columbia made a public commitment to ``share all data
gathered,'' however, to date, CCCEH has not provided EPA with the data,
citing subject privacy concerns. In 2018, EPA explored options for
blinding the data to eliminate this concern. However, through these
conversations, CCCEH indicated there is no effective way to remedy this
issue, citing that since the cohort is from a very small geographic
area, subject identification would still be possible, and therefore,
was still of concern.
    In addition, EPA actively sought clarification on the kinds of
residential application methods of chlorpyrifos used in New York City
(NYC) during the time the CCCEH study was conducted (1998-2000) in
order to provide additional context to the results of the CCCEH study
conclusions. Through a series of email and telephone conversations with
NYC pest control officials in 2016, EPA consistently heard that
chlorpyrifos was typically applied as a crack and crevice application
between 1998 and 2000. Unfortunately, EPA has no way to verify that
this use pattern aligns with the exposures of participants in the CCCEH
study and would not be able to corroborate the correlation between
crack and crevice application and the observed neurodevelopmental
effects.
    As indicated, EPA has undertaken considerable efforts to assess the
CCCEH

study, including submitting EPA's evaluation of the CCCEH study to
multiple SAPs. Given that CCCEH has not shared the raw data or the
results of their exploratory analyses, EPA cannot validate or confirm
the data analysis performed, the degree to which the statistical
methods employed were appropriate, or the extent to which (reasonable
or minor) changes in assumptions may have changed any final results or
conclusions. EPA has been unable to conduct its own evaluation of the
study conclusions utilizing the raw data nor has EPA has been able to
address the issues identified by the 2016 SAP. While EPA has retained
the FQPA 10x safety factor in order to address this potential
uncertainty, given the shortcomings to date of the published
epidemiology data, EPA does not have sufficiently complete information
to currently support using the epidemiology studies as the POD in place
of AChE inhibition as the POD.
    In conclusion, the epidemiologic studies are central to the
Petitioner's claims regarding neurodevelopmental effects, yet the
Petitioners and Objectors rely only on summaries in publications to
present their case. Petitioners have not presented the raw data from
the epidemiology studies for consideration of their claims. EPA has
likewise been unable to obtain this critical information, though the
FIFRA SAP and commenters have raised many questions about it. So, EPA
has not been able to verify the conclusions of the epidemiology studies
due to this lack of raw data. Further, the lack of a clear mechanism of
action and the lack of an internationally accepted dosing regimen in
the in vivo data also preclude EPA from determining the relevance of
the limited animal data addressing the potential for neurodevelopmental
effects. The Petitioners have therefore failed to meet their initial
burden of providing sufficiently valid, complete, and reliable evidence
that neurodevelopmental effects may be occuring at levels below EPA's
current regulatory standard and no information submitted with the
objections addresses this shortcoming of the Petition.
    2. Reconciling FFDCA petitions to revoke and FIFRA Registration
Review. EPA also continues to conclude that denial is appropriate for
claims related to matters that are the subject of registration review,
specifically for chlorpyrifos, claims related to neurodevelopmental
toxicity. In this case, the data deficiencies in the Petition related
to neurodevelopmental toxicity that EPA is currently studying in a more
up-to-date, thorough and methodical fashion in conjunction with the
statutorily prescribed FIFRA re-registration process. In this context,
it is particularly appropriate for EPA to take into account the
substantive work that it is conducting under FIFRA in reaching its
decision on the Petition.
    As EPA explained in the Denial Order, to reconcile the FFDCA
petition procedures with the FIFRA registration review provisions that
require EPA to conduct periodic reviews of all pesticides, EPA must be
able to take account of the FIFRA registration review schedule for a
pesticide in determining how and when to respond to an FFDCA petition
that raises issues that are also the subject of a current registration
review. As noted, the Denial Order fully responded to Petitioners'
claims that address the substance of EPA's 2006 safety finding, and
Petitioners and the other Objectors could have chosen to challenge and
litigate that determination through the petition and judicial review
provisions of the FFDCA, had they wished. The objections, however, do
not for the most part go to the substance of EPA's 2006 safety finding.
Those claims have largely been abandoned and instead the objections now
focus only on compelling EPA to resolve on a petitioner-dictated
schedule new issues regarding the potential for neurodevelopmental
toxicity that are part of an ongoing evaluation in registration review
in advance of the statutory deadline (October 1, 2022) provided by
Congress in FIFRA section 3(g) for completing that assessment. To that
end, Objectors argue that the fact Congress established a 2022 deadline
for registration review is no license for EPA to delay its response to
an FFDCA petition and that EPA is in fact prohibited from relying on
registration review as a basis for determining how to complete other
reviews of a pesticide. Specifically, they cite to language in FIFRA
section 3(g)(1)(C) that states that ``[n]othing in this subsection
shall prohibit the Administrator from undertaking any other review of a
pesticide under this chapter.'' Objectors have overlooked the critical
language at the end of this passage (``under this chapter'') that by
its terms only speaks to how EPA should reconcile registration review
with other reviews under FIFRA. The language does not address reviews
under the FFDCA, much less prohibit EPA from reconciling its responses
to FFDCA petitions with the timeframe for registration review under
FIFRA. The Objectors also do not point to any language in the FFDCA
prohibiting the reconciliation of a response to a petition to revoke
tolerances with the registration review schedule for reviewing the
pesticide--which includes a determination whether to leave existing
tolerances in effect. The 15-year registration review interval reflects
Congress's effort to balance the need for EPA to assure that pesticides
meet the FFDCA and FIFRA standards, while at the same time recognizing
that completing scientific evaluations for over 1000 active ingredients
is both time-consuming and resource-intensive. During a registration
review, EPA is required to ``assess changes since a pesticide's last
[registration] review,'' including new risk assessment methods, new
studies and new data on pesticides. 40 CFR 155.53(a). This is precisely
the assessment EPA is in the process of undertaking in the chlorpyrifos
registration review with respect to the Petition claims addressing new
information on the potential for adverse neurodevelopmental effects.
If, as Petitioners and Objectors argue, EPA were required to truncate
its ongoing registration review process to make a new FFDCA safety
finding every time it received a petition to modify or revoke
tolerances, petitioners would effectively have the authority to re-
order the Administrator's scheduling of registration review decisions
under FIFRA and dictate the extent of inquiry EPA may put to a matter
before reaching a resolution. EPA continues to believe that with the
passage of FIFRA section 3(g) and the 15-year review cycle created by
that provision, Congress directed the Administrator, not FFDCA
petitioners, to determine the appropriate timing and process for
completing the review of dietary risk within that 15-year review
period. EPA therefore concludes that it is also appropriate to deny the
objections and the underlying petition to the extent they seek to
compel EPA's consideration of neurodevelopmental toxicity issues raised
during the course of the current registration review in advance of the
schedule provided by Congress under FIFRA section 3(g).
    As described previously, EPA has compelling reasons to follow its
regulatory process through registration review. Specifically, EPA is
working to update a number of assessments that will result in a more
complete, accurate assessment of the risks of chlorpyrifos than if EPA
were compelled to truncate that review now. The key components of EPA's
updates to its analysis are (1) Review of five new laboratory animal
studies for consideration in the updated human health risk assessment,
and (2) Incorporating refined use information

into the 2016 updated drinking water assessment.
    With respect to the animal data, in 2018, the California Department
of Pesticide Regulation (CDPR) proposed to adopt a regulation
designating chlorpyrifos as a toxic air contaminant (TAC) in
California. As part of this determination, CDPR developed its ``Final
Toxic Air Contaminant Evaluation of Chlorpyrifos Risk Characterization
of Spray Drift, Dietary, and Aggregate Exposures to Residential
Bystanders.'' The CDPR risk characterization document cites five new
laboratory animal studies not previously reviewed by EPA (Gomez-Gimenez
et al., 2017, 2018; Silva et al., 2017; Lee et al., 2015; Carr et al.,
2017). It is appropriate for EPA to review these five new studies in
order to complete EPA's evaluation of potential neurodevelopmental
effects. CDPR is using these studies as the main source of information
for their new POD for acute oral exposure, so it is prudent for EPA to
evaluate the data's quality and whether it provides the strong support
for the conclusion that effects on the developing brain may occur below
a dose eliciting 10% AChE inhibition that would be used to establish a
new POD for the EPA's risk assessment. EPA is conducting its review in
accordance with OPP's Guidance for Considering and Using Open
Literature Toxicity Studies to Support Human Health Risk Assessment. It
has contacted the primary investigators associated with the new animal
studies in July-August 2018, and received the raw data associated with
one of these studies.
    As for EPA's drinking water assessment, the Agency identified
certain uses, application rates, and practices described in the current
chlorpyrifos labels that are not actually being used in the field and
are contributing to an over-estimate of potential drinking water
concentrations. EPA has requested additional information from the
registrants to confirm the accuracy of these assumptions and
anticipates including these updates in the Proposed Interim Decision.
    To be clear, EPA remains committed to expediting its registration
review determination so that it is completed well in advance of the
October 2022 deadline. To that end, EPA anticipates making available
any updates to the human health and drinking water assessments for
public availability and comment by summer of 2020. Updates will also
include EPA's response to public comments from the previous comment
periods. In addition, EPA has been engaged in discussions with the
chlorpyrifos registrants that could result in further use limitations
affecting the outcome of EPA's assessment. The Proposed Interim
Decision incorporating these updated assessments is anticipated for
public availability and comment by October 2020. If EPA were compelled
to act in advance of these registration review activities, none of
these assessments would be available to inform that review. For
example, OPP is pursuing the use of surface water monitoring data to
confidently estimate pesticide concentrations in surface water that may
be sourced by community water systems. A meeting of the FIFRA
Scientific Advisory Panel is planned for obtaining expert feedback on
tools and methodologies currently in development for using surface
water monitoring data quantitatively in drinking water assessments.
While the focus of the SAP is not specific to chlorpyrifos, the EPA
will consider any recommendations from the SAP that are appropriate for
inclusion in the chlorpyrifos drinking water assessment.

B. Objections Asserting That EPA Has Found Chlorpyrifos To Be Unsafe

    The Objectors argue that EPA not only failed to make a safety
finding in denying the Petition, but that it has never disavowed
previous EPA findings that it could not conclude chlorpyrifos is safe
with respect to both the potential for adverse neurodevelopmental
effects and harmful drinking water exposures. In particular, the
objections point to various statements in EPA risk assessments and in
EPA's 2015 proposed tolerance revocation action asserting that EPA is
unable to conclude that chlorpyrifos tolerances are safe.
    Contrary to these assertions, as noted by Corteva in its response
to the objections, EPA has not made any findings that chlorpyrifos
tolerances are not safe. In fact, EPA's last final action with respect
to the safety of chlorpyrifos tolerances was its determination in 2006
that chlorpyrifos and the other pesticides in the organophosphate class
meet the FFDCA safety standard in connection with FIFRA section 4
reregistration and FFDCA section 408(q) tolerance reassessment. This is
the only regulatory finding currently in effect for chlorpyrifos as EPA
has taken no final action on the proposed rule it published in 2015 to
comply with the Ninth Circuit mandamus order in the PANNA v. EPA
decision. Proposed rules are just that--proposals; they do not bind
federal agencies. Indeed, EPA made clear it was issuing the proposal
because of the court order, without having resolved many of the issues
critical to EPA's FFDCA determination and without having fully
considered comments previously submitted to the Agency (69 FR 69079,
69081-83). Similarly, risk assessments that underly proposed rules are
not final agency actions and likewise are not binding.
    At this stage, EPA may choose to finalize, modify or withdraw the
proposal based on the comments received and EPA's evaluation following
its review of the comments. Until such time, EPA's statements in the
proposed rule are not binding pronouncements with respect to EPA's
decision whether to grant or deny the Petition. See, e.g., Northwest
Coalition for Alternatives to Pesticides v. EPA, 544 F.3d 1043, 1051
(9th Cir. 2008) (``as long as agencies follow the proper administrative
procedures, they have the authority to change their minds before
issuing a final order''); Public Citizen Health Research Grp. v. FDA,
740 F.2d 21 (D.C. Cir. 1984) (``Neither the substance of the decision
to require further study nor the circumstances leading to the decision
. . . suffice, however, to permit us to leapfrog back over the
Secretary's decision . . . hold the agency to its preliminary decision
to promulgate a labeling requirement. In connection with the
registration review of chlorpyrifos, which EPA expects to complete in
advance of the October 1, 2022 statutory deadline, EPA will make a
determination regarding the safety of chlorpyrifos and will either
finalize, modify or withdraw the proposal at that time.
    With respect to objections related to drinking water, as explained
in Unit II., a party may not raise issues in objections unless they
were part of the petition. Corn Growers v. EPA, 613 F.3d 266 (D.C. Cir.
2010), cert. denied, 131 S. Ct. 2931 (2011). The Petition did not
identify drinking water exposure as a basis for seeking tolerance
revocation, and the Objectors cannot therefore raise that concern as a
basis for challenging EPA's denial of the Petition. The mere fact that
EPA is considering the potential impact of chlorpyrifos exposures in
drinking water in the Agency's FIFRA section 3(g) registration review
does not somehow provide Petitioners and Objectors with a vehicle for
introducing that topic in the objections process on the Petition
denial. And the objections phase of the petition process does not
provide Petitioners a means to effectively start the petition process
over again by raising issues that were not originally raised in the
2007 petition to revoke. Accordingly, EPA denies all objections
regarding drinking water exposures. To be clear, however, EPA is
continuing its

FIFRA section 3(g) registration review and to complete its evaluation
of drinking water exposures to chlorpyrifos. EPA will address these
issues in its upcoming registration review decision.

C. Objections Asserting That the Denial Order Failed To Respond to
Significant Concerns Raised in Comments

    The Objectors claim that EPA has committed procedural error in
failing to respond to certain comments raised in comments to EPA's 2014
Revised Human Health Risk Assessment and the 2015 proposed revocation.
The Objectors appear to assert that in the absence of any comment
response document in the record, EPA has violated the requirements of
section 553(c) of the Administrative Procedure Act (APA) which requires
agencies to give consideration to relevant matter submitted during the
comment period on proposed rules. While these objections correctly
recite the requirements of the APA rulemaking provisions, the
requirement to respond to comments on proposed rules applies to the
``rules adopted'' by agencies--i.e., final rules--and EPA has neither
finalized nor withdrawn the 2015 proposed revocation rule. Further, the
FFDCA does not require EPA to respond to rulemaking comments in issuing
petition denial orders under FFDCA section 408(d)(4). In connection
with EPA's completion of the FIFRA section 3(g) registration review of
chlorpyrifos, EPA will either finalize or withdraw the proposed rule
and address significant comments on the proposal at that time. But EPA
has no obligation to respond to rulemaking comments in denying the
Petition or responding to objections, both of which are adjudicatory
actions that are not part of the rulemaking process.
    In addition to raising procedural error, Objectors appear to adopt
as their own substantive objections some of the comments on the
proposed rule and risk assessment. Specifically, they focus on comments
asserting that (1) EPA's use of 10% cholinesterase as a regulatory
standard is not protective for effects to children's developing brains;
(2) EPA inappropriately used Corteva's PBPK model, which is ethically
and scientifically deficient, to reduce inter and intra-species safety
factors; and (3) EPA has not properly accounted for effects from
inhalation of chlorpyrifos from spray drift and volatilization.
    The comments adopted by the Objectors regarding effects on the
developing brain mirror the claims raised in the Petition regarding the
potential for adverse neurodevelopmental effects. Accordingly, EPA
restates its response provided in Unit VII.A.1. that the Petition and
the objections fail to meet burden of presenting evidence sufficiently
valid, complete and reliable to demonstrate that chlorpyrifos results
in neurodevelopmental effects that render its tolerances not safe.
    With respect to EPA's use of the Corteva PBPK model, these claims,
as with claims respecting drinking water, were not raised in the
Petition and cannot be raised for the first time in the objections
phase of the petition process. Further, the Objections appear to oppose
EPA's use of the PBPK model in conducting the assessment underlying
EPA's 2014 and 2016 risk assessments and 2015 proposed tolerance
revocation and do not appear to address EPA's Petition denial. This
objection therefore does not appear to be relevant to the Denial Order.
For these reasons, this objection is also denied.
    Regarding the objections related to inhalation risk, Objectors
raise three distinct issues from the public comments that relate to
EPA's completed inhalation exposure assessment addressing the potential
for bystanders to experience cholinesterase inhibition from exposure to
spray drift at the time of application and volatilized chlorpyrifos
following application. First, the Objectors dispute EPA' s legal
authority not to consider in its risk assessment exposures to
chlorpyrifos from illegal spraying prohibited by product labeling.
Second, the Objectors assert that the Denial Order inappropriately
relied on two recent Corteva studies on the effects of chlorpyrifos in
its vapor phase to conclude that volatilized chlorpyrifos presents no
risk of cholinesterase inhibition. Third, the Objectors assert that
documented poisoning incidents demonstrate that the no-spray buffer-
zones that EPA approved on product labeling in 2012 are inadequate to
address harm from spray drift. Objectors point specifically to a May
2017 poisoning incident in Kern County, California, involving a total
of 50 people who were either harmed or put at risk, as evidence for
their concern.
    In response, EPA believes it is lawful and appropriate for it to
consider federally enforceable chlorpyrifos product labeling
restrictions in assessing the extent of bystander risk from spray drift
under both the FFDCA and FIFRA. Under FIFRA, pesticide labeling use
instructions are enforceable limits on the use of the product that
serve as the basis for EPA's evaluation of potential risks. Indeed, in
registering pesticides, FIFRA section 3(c)(5) directs EPA to register
pesticides when, among other things, a pesticide ``will perform its
intended function without unreasonable effects on the environment'' and
``when used in accordance with widespread and commonly recognized
practice it will not generally cause unreasonable adverse effects on
the environment.'' These directives functionally instruct EPA to
consider the intended, widespread and commonly recognized use of a
pesticide as set forth on proposed product labeling in determining
whether the pesticide will cause unreasonable adverse on the
environment. While these provisions do not serve as a bar to EPA
considering the impacts from unlawful misuse, unless such misuse is a
widespread or commonly recognized practice, it does not provide a basis
for regulatory action under FIFRA or a basis for determining that
current tolerance levels are unsafe. Rather, misuse is first and
foremost a matter for enforcement under FIFRA. It should also be noted
that because chlorpyrifos is a restricted use pesticide, applicators
must have specific training meant, in part, to assure proper pesticide
application. When these restrictions are followed, exposures are
significantly limited. To be clear, while drift is minimized when
applicators follow label directions, EPA does assume that some residues
may settle off-target, and that there may be dermal and incidental oral
exposure from contacting residential turf adjacent to treated fields.
To address the potential for cholinesterase inhibition from these
exposures, EPA assessed the risk from these exposures and establishes
appropriate distances between such locations and the site of
application. Accordingly, following EPA's assessment of spray drift in
2012, the chlorpyrifos registrants agreed to place additional
limitations on use to include use rate reductions and spray drift
buffers that are sufficient to eliminate a risk of cholinesterase
inhibition from lawful use.
    With respect to the objections concerning volatility and the
potential for cholinesterase inhibition, EPA has not changed its
position set forth in the Denial Order and does not believe it is
disregarding the potential for volatilization exposures. Exposure to
low levels of vapor-phase chlorpyrifos following application near
treated fields is possible. After the Agency's 2011 preliminary risk
assessment, Corteva submitted toxicity data that measured
cholinesterase inhibition resulting from acute exposure to vapors of
chlorpyrifos and its oxon rather than exposure to

aerosols of these compounds as was done for previous assessments. Since
inhalation exposure to bystanders will be only to vapor phase
chlorpyrifos rather than aerosols due to spray drift restrictions, use
of these data to assess inhalation risk of cholinesterase inhibition to
bystanders is appropriate. In these vapor-phase toxicity studies, test
animals were exposed in atmospheres containing saturation
concentrations of chlorpyrifos and its oxon, the maximum potential
level of the compounds in air. No cholinesterase inhibition was
observed, and the studies were determined to have been conducted
properly using saturation concentrations of the compounds and controls
appropriate for these types of studies, i.e., animals receiving no
pesticide exposure, as further explained in ``Chlorpyrifos:
Reevaluation of the Potential Risks from Volatilization in
Consideration of Chlorpyrifos Parent and Oxon Vapor Inhalation Toxicity
Studies, W. Britton, W. Irwin, 6/25/14.''
    EPA has also done a comprehensive review of chlorpyrifos incidents
and found that most were due to accidents and misuse as specified in
EPA's most recent final incident review ``Chlorpyrifos: Tier II
Incident Report, S. Recore and K. Oo, 7/27/11.'' The agency is aware of
the referenced Kern County chlorpyrifos incident that occurred in 2017
in which the pesticide appears to have been applied in a manner in
which direct drift onto bystanders occurred, a case of misuse. Spray
drift buffers address exposure to bystanders when chlorpyrifos is
applied as required by the pesticide label. In addition, it should be
noted that EPA's 2000 cancellation of homeowner products and many
indoor and outdoor non-residential uses (e.g., schools and parks where
children may be exposed) has led, according to data from 2002-2010, to
a 95% decrease in the number of incidents reported in residential
areas. In sum, EPA does not believe available incident data suggests
that there exists a widespread and commonly recognized practice of
misusing chlorpyrifos and EPA therefore believes it is appropriate to
use the enforceable label instructions as the basis for evaluating the
potential for inhalation exposure from spray drift and volatilization.

VIII. Regulatory Assessment Requirements

    As indicated previously, this action announces the Agency's order
denying objections filed under FFDCA section 408. As such, this action
is an adjudication and not a rule. The regulatory assessment
requirements imposed on rulemaking do not, therefore, apply to this
action.

IX. Submission to Congress and the Comptroller General

    The Congressional Review Act, 5 U.S.C. 801 et seq., does not apply
because this action is not a rule for purposes of 5 U.S.C. 804(3).

X. References

    The following is a listing of the documents that are specifically
referenced in this document. The docket includes these documents and
other information considered by EPA, including documents that are
referenced within the documents that are included in the docket, even
if the referenced document is not physically located in the docket. For
assistance in locating these other documents, please consult the person
listed under FOR FURTHER INFORMATION CONTACT.

1. The Petition from NRDC and PANNA and EPA's various responses to
it are available in docket number EPA-HQ-OPP-2007-1005 available at
http://www.regulations.gov.
2. The objections submitted on the Petition Denial are available in
docket number EPA-HQ-OPP-2007-1005 available at http://www.regulations.gov.
3. For additional information on the organophosphate cumulative risk
assessment, see http://www.epa.gov/pesticides/cumulative/2006-op/op_cra_main.pdf.
4. FIFRA Scientific Advisory Panel (2016). ``Chlorpyrifos: Analysis
of Biomonitoring Data''. Available at: https://www.epa.gov/sap/meeting-materials-april-19-21-2016-scientific-advisory-panel.
5. For additional information on the 2000 chlorpyrifos IRED and 2006
chlorpyrifos RED, see https://www3.epa.gov/pesticides/chem_search/reg_actions/reregistration/red_PC-059101_1-Jul-06.pdf.
6. FIFRA Scientific Advisory Panel (2008). ``Scientific Issues
Associated with Chlorpyrifos and PON1''. Available in docket number
EPA-HQ-OPP-2008-0274 available at http://www.regulations.gov.
7. EPA, 2012. ``Guidance for Considering and Using Open Literature
Toxicity Studies to Support Human Health Risk Assessment'' as well
as it's ``Framework for Incorporating Human Epidemiologic & Incident
Data in Health Risk Assessment.'' Available at https://www.epa.gov/sites/production/files/2015-07/documents/lit-studies.pdf.
8. EPA, 2016. Record of Correspondence. Available in docket number
EPA-HQ-OPP-2015-0653.

List of Subjects in 40 CFR Part 180

    Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
recordkeeping requirements.

    Dated: July 18, 2019.
Alexandra Dapolito Dunn,
Assistant Administrator, Office of Chemical Safety and Pollution
Prevention.
[FR Doc. 2019-15649 Filed 7-23-19; 8:45 am]
 BILLING CODE 6560-50-P