Document ID: EPA-HQ-OPP-2008-0347-0039
Agency: epa
Document Type: Rule
Title: Order Denying NRDC's Objections and Requests for Hearing: Carbaryl
Posted Date: 2010-09-15T04:00Z

[Federal Register: September 15, 2010 (Volume 75, Number 178)]
[Rules and Regulations]               
[Page 55997-56013]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr15se10-18]                         

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ENVIRONMENTAL PROTECTION AGENCY

[EPA-HQ-OPP-2008-0347; FRL-8843-7]

40 CFR Part 180

 
Carbaryl; Order Denying NRDC's Objections and Requests for 
Hearing

AGENCY: Environmental Protection Agency (EPA).

ACTION: Order.

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SUMMARY: In this order, the Environmental Protection Agency (EPA) 
denies objections, and requests for hearing on those objections, to a 
prior order denying a petition requesting that EPA revoke all pesticide 
tolerances for carbaryl under section 408(d) of the Federal Food, Drug, 
and Cosmetic Act. The objections and hearing requests were filed on 
December 29, 2008, by the Natural Resources Defense Council (NRDC). The 
original petition was also filed by NRDC.

FOR FURTHER INFORMATION CONTACT: Jacqueline Guerry, Pesticide Re-
evaluation Division (7508P), Office of Pesticide Programs, 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001; telephone number: (215) 814-2184; e-mail 
address: guerry.jacqueline@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    In this document, EPA denies objections, and requests for hearing 
on those objections, submitted by NRDC in response to a prior order 
denying NRDC's petition requesting that EPA revoke all pesticide 
tolerances for carbaryl. In addition to NRDC, and others interested in 
food safety issues generally, this action may be of interest to 
agricultural producers, food manufacturers, or pesticide manufacturers. 
Potentially affected entities may include, but are not limited to those 
engaged in the following activities:
     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.
    This listing is not intended to be exhaustive, but rather to 
provide a guide for readers regarding entities likely to be affected by 
this action. Other types of entities not listed in this unit could also 
be affected. The North American Industrial Classification System 
(NAICS) codes have been provided to assist you and others in 
determining whether this action might apply to certain entities. If you 
have any questions regarding the applicability of this action to a 
particular entity, consult the person listed under FOR FURTHER 
INFORMATION CONTACT.

B. How Can I Get Copies of this Document and Other Related Information?

    EPA has established a docket for this action under docket 
identification (ID) number EPA-HQ-OPP-2008-0347. Publicly available 
docket materials are available either in the electronic docket at 
http://www.regulations.gov, or, if only available in hard copy, at the 
Office of Pesticide Programs (OPP) Regulatory Public Docket in Rm. S-
4400, One Potomac Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, 
VA. The hours of operation of this Docket Facility are from 8:30 a.m. 
to 4 p.m., Monday through Friday, excluding legal holidays. The Docket 
Facility telephone number is (703) 305-5805.

II. Introduction

A. What Action Is the Agency Taking?

    In this order, EPA denies objections, and requests for a hearing on 
those objections, to an earlier EPA Order, (73 FR 64229 ), denying a 
petition to revoke all tolerances established for the pesticide, 
carbaryl, under the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 
U.S.C. 346a, (Refs. 1 and 2). Both the objections and hearing requests, 
as well as the petition, were filed with EPA by NRDC.
    NRDC's original petition, dated January 10, 2005, submitted to the 
carbaryl public docket during the public comment period for the 2004 
Amended Interim Reregistration Eligibility Decision (IRED) for 
Carbaryl, and filed pursuant to FFDCA section 408(d)(1), asserted a 
number of grounds why carbaryl tolerances allegedly fail to meet the 
FFDCA's safety standard. The main arguments raised in the petition 
concerned EPA's drinking water assessment and EPA's decision on the 
statutory safety factor to protect infants and children that supported 
the 2004 IRED decision. NRDC also petitioned the Agency to cancel all 
carbaryl uses pursuant to the Federal Insecticide, Fungicide, and 
Rodenticide Act (FIFRA) 7 U.S.C. 136(bb) and 136a, and argued 
unreasonable risks on the environment. Subsequently, on November 26, 
2007, NRDC petitioned EPA to cancel all carbaryl pet collar uses under 
FIFRA. (Ref. 3). EPA consolidated this latter petition with the 2005 
FFDCA petition because NRDC argued in it that exposure to carbaryl pet 
collars make the risks presented by carbaryl unsafe within the meaning 
of FFDCA section 408.
    On October 29, 2008, EPA responded to both the 2005 petition to 
revoke all carbaryl tolerances and the 2007 petition to cancel all pet 
collar uses, denying them in their entirety. (73 FR 64229, October 29, 
2008) (Ref. 4).
    NRDC then filed objections to EPA's denial of NRDC's petition to 
revoke all carbaryl tolerances and requested a hearing on its 
objections. These objections and hearing requests were filed pursuant 
to the procedures in the FFDCA, section 408(g)(2). (21 U.S.C. 
346a(g)(2)). The objections narrowed NRDC's claims to two main topics - 
that EPA lacks reliable data to reduce the Food Quality Protection Act 
(FQPA) Children's Safety Factor and that EPA's exposure assessment for 
carbaryl is flawed and underestimates the exposure to children from pet 
collar uses. After carefully reviewing the objections and hearing 
requests, EPA has determined that NRDC's hearing requests do not 
satisfy the regulatory requirements for such requests and that its 
substantive objections are without merit. Therefore, EPA, in this final 
order, denies NRDC's

[[Page 55998]]

objections and its requests for a hearing on those objections.

B. What is the Agency's Authority for Taking This Action?

    NRDC petitioned to revoke the carbaryl tolerances pursuant to the 
petition procedures in FFDCA section 408(d)(1). (21 U.S.C. 346a(d)(1)). 
Under section 408(d), EPA may respond to such a petition by either 
issuing a final or proposed rule modifying or revoking the tolerances 
or issuing an order denying the petition. (21 U.S.C. 346a(d)(4)). Here, 
EPA responded by issuing an order under section 408(d)(4)(iii) denying 
the petition. (73 FR 64229, October 29, 2008).
    Orders issued under section 408(d)(4)(iii) are subject to a 
statutorily-created administrative review process. (21 U.S.C. 
346a(g)(2)). Any person may file objections to a section 408(d)(4)(iii) 
order with EPA and request a hearing on those objections. (Id.). EPA is 
required by section 408(g)(2)(C) to issue a final order resolving the 
objections to the section 408(d)(4)(iii) order. (21 U.S.C. 
346a(g)(2)(C)).

III. Statutory and Regulatory Background

    In this Unit, EPA provides background on the relevant statutes and 
regulations governing NRDC's objections and requests for hearing as 
well as on pertinent Agency policies and practices. As noted, NRDC's 
objections and requests for hearing raise two main claims: (1) that EPA 
has unlawfully failed to retain the full tenfold FQPA safety factor for 
the protection of infants and children and failed to apply an 
additional threefold factor due to a deficiency in a critical study; 
and (2) that EPA underestimated the exposure to children from pet 
collar uses. The first claim is based on assertions that additional 
safety factors are needed because of effects observed in a 
developmental neurotoxicity (DNT) study with carbaryl. The pet collar 
claim is primarily based upon allegations that EPA does not have 
sufficient or reliable data with which to assess pet collar exposures 
and that the assumptions made by EPA underestimate exposure to 
children. Background information on each of these topics is included in 
this Unit.
    Unit III.A. summarizes the requirements and procedures in section 
408 of the FFDCA and applicable regulations pertaining to pesticide 
tolerances, including the procedures for petitioning for revocation of 
tolerances and challenging the denial of such petitions and the 
substantive standards for evaluating the safety of pesticide 
tolerances. This unit also discusses the closely-related statute under 
which EPA regulates the sale, distribution, and use of pesticides, 
FIFRA, (7 U.S.C. 136 et seq.).
    Unit III.B. provides an overview of EPA's risk assessment process. 
It contains an explanation of how EPA identifies the hazards posed by 
pesticides, how EPA determines the level of exposure to pesticides that 
pose a concern (level of concern), how EPA measures human exposure to 
pesticides, and how hazard, level of concern conclusions, and human 
exposure estimates are combined to evaluate risk. Further, this unit 
presents background information on Agency policies with particular 
relevance to this action.

A. FFDCA/FIFRA and Applicable Regulations

    1. In general. EPA establishes maximum residue limits, or 
``tolerances,'' for pesticide residues in food under section 408 of the 
FFDCA. (21 U.S.C. 346a). Without such a tolerance or an exemption from 
the requirement of a tolerance, a food containing a pesticide residue 
is ``adulterated'' under section 402 of the FFDCA and may not be 
legally moved in interstate commerce. (21 U.S.C. 331, 342). Monitoring 
and enforcement of pesticide tolerances are carried out by the U.S. 
Food and Drug Administration (FDA) and the U.S. Department of 
Agriculture (USDA). Section 408 was substantially rewritten by the Food 
Quality Protection Act of 1996 (FQPA), which added the provisions 
discussed below establishing a detailed safety standard for pesticides, 
additional protections for infants and children, and the estrogenic 
substances screening program. (Public Law 104-170, 110 Stat. 1489 
(1996)).
    EPA also regulates pesticides under FIFRA, (7 U.S.C. 136 et seq). 
While the FFDCA authorizes the establishment of legal limits for 
pesticide residues in food, FIFRA requires the approval of pesticides 
prior to their sale and distribution, (7 U.S.C. 136a(a)), 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. (7 U.S.C. 136j(a)(2)(G)). 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 as to pesticide uses which result in dietary risk 
from residues in or on food, (7 U.S.C. 136(bb)), and directing that EPA 
coordinate, to the extent practicable, revocations of tolerances with 
pesticide cancellations under FIFRA. (21 U.S.C. 346a(l)(1)).
    2. Safety standard for pesticide tolerances. A pesticide tolerance 
may only be promulgated by EPA if the tolerance is ``safe.'' (21 U.S.C. 
346a(b)(2)(A)(i)). ``Safe'' is defined by the statute 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.'' (21 U.S.C. 346a(b)(2)(A)(ii)). Section 
408(b)(2)(D) directs EPA, in making a safety determination, to:
     consider, among other relevant factors- ...
     (v) available information concerning the cumulative effects of 
such residues and other substances that have a common mechanism of 
toxicity;
     (vi) available information concerning the aggregate exposure 
levels of consumers (and major identifiable subgroups of consumers) to 
the pesticide chemical residue and to other related substances, 
including dietary exposure under the tolerance and all other tolerances 
in effect for the pesticide chemical residue, and exposure from other 
non-occupational sources;
     (viii) such information as the Administrator may require on 
whether the pesticide chemical may have an effect in humans that is 
similar to an effect produced by a naturally occurring estrogen or 
other endocrine effects. ... EPA must also consider, in evaluating the 
safety of tolerances, ``safety factors which . . . are generally 
recognized as appropriate for the use of animal experimentation data.''
(21 U.S.C. 346a(b)(2)(D)(ix).
    Risks to infants and children are given special consideration. 
Specifically, section 408(b)(2)(C) states that EPA:
     shall assess the risk of the pesticide chemical based on-- ...
     (II) 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; and
     (III) available information concerning the cumulative effects

[[Page 55999]]

on infants and children of such residues and other substances that have 
a common mechanism of toxicity. ...
    This provision also creates a presumptive 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.). The additional safety margin for infants and children is 
referred to throughout this order as the ``children's safety factor.''
    3. Procedures for establishing, amending, or revoking tolerances. 
Tolerances are established, amended, 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, 
amend, or revoke a tolerance by means of filing a petition with EPA. 
(See 21 U.S.C. 346a(d)(1)). EPA publishes in the Federal Register a 
notice of the petition filing and requests public comment. (21 U.S.C. 
346a(d)(3)). After reviewing the petition, and any comments received on 
it, EPA may issue a final rule establishing, amending, or revoking the 
tolerance, issue a proposed rule to do the same, or deny the petition. 
(21 U.S.C. 346a(d)(4)).
    Once EPA takes final action on the petition by either establishing, 
amending, or revoking the tolerance or denying the petition, any person 
may file objections with EPA and seek an evidentiary hearing on those 
objections. (21 U.S.C. 346a(g)(2)). Objections and hearing requests 
must be filed within 60 days. (Id.). The statute provides that EPA 
shall ``hold a public evidentiary hearing if and to the extent the 
Administrator determines that such a public hearing is necessary to 
receive factual evidence relevant to material issues of fact raised by 
the objections.'' (21 U.S.C. 346a(g)(2)(B). EPA regulations make clear 
that hearings will only be granted where it is shown that there is ``a 
genuine and substantial issue of fact,'' the requestor has identified 
evidence ``which, if established, resolve one or more of such issues in 
favor of the requestor,'' and the issue is ``determinative'' with 
regard to the relief requested. (40 CFR 178.32(b)). In addition, EPA 
regulations prescribe the form and manner of submissions for objections 
and for an evidentiary hearing. (40 CFR 178.25 and 178.27). EPA's final 
order on the objections is subject to judicial review. (21 U.S.C. 
346a(h)(1)).
    4. Tolerance reassessment and FIFRA reregistration. The FQPA 
required that EPA reassess the safety of all pesticide tolerances 
existing at the time of its enactment. (21 U.S.C. 346a(q)). EPA was 
given 10 years to reassess the approximately 10,000 tolerances in 
existence in 1996. In this reassessment, EPA was required to review 
existing pesticide tolerances under the new ``reasonable certainty that 
no harm will result'' standard set forth in section 408(b)(2)(A)(i). 
(21 U.S.C. 346a(b)(2)(A)(i)). This reassessment was substantially 
completed by the August 3, 2006 deadline. Tolerance reassessment was 
generally handled in conjunction with a similar program involving 
reregistration of pesticides under FIFRA. (7 U.S.C. 136a-1). 
Reassessment and reregistration decisions were generally combined in a 
document labeled a Reregistration Eligibility Decision (RED).

B. EPA Risk Assessment for Tolerances--Policy and Practice

    1. The safety determination - risk assessment. To assess risk of a 
pesticide tolerance, EPA combines information on pesticide toxicity 
with information regarding the route, magnitude, and duration of 
exposure to the pesticide. The risk assessment process involves four 
distinct steps:
     Identification of the toxicological hazards posed by a 
pesticide;
     Determination of the dose-response analysis in test 
animals and ``level of concern'' with respect to human exposure to the 
pesticide;
     Estimation of human exposure to the pesticide; and
     Characterization of risk posed to humans by the pesticide 
based on comparison of human exposure to the level of concern.
    a. Hazard identification. In evaluating toxicity or hazard, EPA 
reviews toxicity studies, primarily in laboratory animals, to identify 
any adverse effects on the test subjects. Animal studies typically 
involve investigating a broad range of effects including gross and 
microscopic effects on organs and tissues, functional effects on bodily 
organs and systems, effects on blood parameters (such as red blood cell 
count, hemoglobin concentration, hematocrit, and a measure of clotting 
potential), effects on the concentrations of normal blood chemicals 
(including glucose, total cholesterol, urea nitrogen, creatinine, total 
protein, total bilirubin, albumin, hormones, and enzymes such as 
alkaline phosphatase, alanine aminotransfersase and cholinesterase), 
and behavioral or other gross effects identified through clinical 
observation and measurement. EPA examines whether adverse effects are 
caused by different durations of exposure ranging from short-term 
(e.g., acute) to longer-term (e.g., chronic) pesticide exposure, and 
different routes of exposure (oral, dermal, inhalation). EPA also 
evaluates potential adverse effects in different age groups. EPA 
requires testing for different durations and routes of exposure and 
different age groups in multiple species of laboratory animals (e.g., 
rat, mouse, dog, rabbit).
    EPA also considers whether the adverse effect has a threshold - a 
level below which exposure has no appreciable chance of causing the 
adverse effect. For non-threshold effects, EPA assumes that any 
exposure to the substance increases the risk that the adverse effect 
may occur. At present, EPA only considers one adverse effect, the 
chronic effect of cancer, to potentially be a non-threshold effect. 
(Ref. 5 at 8-9). Because this matter involves a pesticide with 
threshold effects, assessment of non-threshold effects is not further 
discussed. Moreover, the toxic effects of carbaryl are short in 
duration (1 day or less) and, as such, long-term, chronic threshold 
effects are not discussed further here.
    b. Level of concern/dose-response analysis. Once a pesticide's 
potential hazards are identified, EPA determines a toxicological level 
of concern for evaluating the risk posed by human exposure to the 
pesticide. In this step of the risk assessment process, EPA essentially 
evaluates the levels of exposure to the pesticide at which effects 
might occur. An important aspect of this determination is assessing the 
relationship between exposure (dose) and response (often referred to as 
the dose-response analysis).
    In examining the dose-response relationship for a pesticide's 
threshold effects, EPA evaluates an array of toxicity studies on the 
pesticide. In each of these studies, EPA attempts to identify the 
lowest observed adverse effect level (LOAEL) and the next lower dose at 
which there are no observed adverse affect levels (NOAEL). Often, EPA 
will use the lowest NOAEL from the relevant available studies -- for 
the duration and route for which risk is being assessed, as a starting 
point (called the Point of Departure (POD)) in estimating the level of 
concern for

[[Page 56000]]

humans. (Ref. 5 at 9 (The POD is simply the ``dose that serves as the 
starting point in extrapolating a risk to the human population.'')). At 
times, however, EPA will use a LOAEL from a study on the most sensitive 
endpoint as the POD when no NOAEL is identified in that study. 
Alternatively, in the absence of a NOAEL for the most sensitive adverse 
effect, EPA will use the LOAEL as the risk assessment POD, and 
determine an extrapolated NOAEL by dividing the LOAEL by an uncertainty 
factor.
    EPA is increasingly using modeling to ascertain what is referred to 
as a Benchmark Dose (BMD) as a substitute for a NOAEL in selecting a 
POD. In its revised assessment of carbaryl, EPA used a BMD approach for 
deriving the POD from the available rat toxicity studies. (Ref. 8). A 
benchmark dose, or BMD, is a point estimate along a dose-response curve 
that corresponds to a specific response level. For example, a 
BMD10 represents a 10% change from the background level (the 
background level is typically derived from the control group). 
Generically, the direction of change from background can be an increase 
or a decrease depending on the biological parameter and the chemical of 
interest. In the case of carbaryl, a reduction in acetylcholinesterase 
(AChE) activity (referred to as ``inhibition'' of AChE) is the toxic 
effect of concern. In addition to a BMD, a ``confidence limit'' may 
also be calculated. Confidence limits express the uncertainty in a BMD 
that may be due to sampling and/or experimental error. The lower 
confidence limit on the dose used as the BMD is termed the BMDL, which 
the Agency uses as the POD. Use of the BMDL for deriving the POD 
rewards better experimental design and procedures that provide more 
precise estimates of the BMD, resulting in tighter confidence 
intervals. Use of the BMDL also helps ensure with high confidence 
(e.g., 95% confidence) that the selected percentage of AChE inhibition 
is not exceeded.
    Numerous scientific peer review panels over the last decade have 
supported the Agency's application of the BMD approach as a 
scientifically supportable method for deriving PODs in human health 
risk assessment, and as an improvement over the historically applied 
approach of using NOAELs or LOAELs. The NOAEL/LOAEL approach does not 
account for the variability and uncertainty in the experimental 
results, which are due to characteristics of the study design, such as 
dose selection, dose spacing, and sample size. With the BMD approach, 
all the dose response data are used to derive a POD. Moreover, the 
response level used for setting regulatory limits can vary based on the 
chemical and/or type of toxic effect (Refs. 6, 7 and 8).
    The POD is, in turn, used in choosing a level of concern. EPA will 
make separate determinations as to the Points of Departure, and 
correspondingly levels of concern, for both short and long exposure 
periods as well as for the different routes of exposure (oral, dermal, 
and inhalation). In estimating and describing the level of concern, the 
POD is at times used differently depending on whether the risk 
assessment addresses dietary or non-dietary exposures. For dietary 
risks, EPA uses the POD to calculate an acceptable level of exposure or 
safe dose. This safe dose has been traditionally referred to as the 
reference dose (RfD). The RfD is defined as the risk assessment POD 
divided by all uncertainty/safety factors (UF/SFs) except those 
specific to FQPA. The Population Adjusted Dose (PAD), on the other 
hand, is defined as the POD divided by all UF/SFs, including those 
specific to FQPA. In cases where there are no UF/SFs specific to FQPA, 
the RfD and PAD are numerically identical. Typically, EPA uses a 
baseline safety/uncertainty factor equal to 100. These factors include 
a factor of 10 (10X) where EPA is using data from laboratory animals 
(inter-species factor) to reflect potentially greater sensitivity in 
humans than laboratory animals and a factor of 10X to account for 
potential variations in sensitivity among members of the human 
population (intra-species factor) as well as other unknowns. Additional 
uncertainty factors may be added to address data deficiencies or 
concerns raised by the existing data. Under the FQPA, a safety factor 
of 10X is presumptively applied to protect infants and children, unless 
reliable data support selection of a different factor. This FQPA safety 
factor largely replaces pre-FQPA EPA practice regarding additional 
safety factors. (Ref. 9 at 4-11).
    c. Estimating human exposure. Risk is a function of both hazard and 
exposure. Thus, equally important to the risk assessment process as 
determining the hazards posed by a pesticide and the toxicological 
level of concern for those hazards is estimating human exposure. Under 
FFDCA section 408, EPA is concerned not only with exposure to pesticide 
residues in food but also exposure resulting from pesticide 
contamination of drinking water supplies and from use of pesticides in 
the home or other non-occupational settings. (See 21 U.S.C. 
346a(b)(2)(D)(vi)). EPA considers multiple routes of exposure (oral, 
dermal, and inhalation) and aggregates these exposures where 
scientifically appropriate. Because EPA exposure estimates are not 
involved in EPA's determination of this matter, no further description 
of EPA exposure assessment practices is included.
    d. Risk characterization. The final step in the risk assessment is 
risk characterization. In this step, EPA combines information from the 
first three steps (hazard identification, level of concern/dose-
response analysis, and human exposure assessment) to quantitatively 
estimate the risks posed by a pesticide. Separate characterizations of 
risk are conducted for different durations of exposure. Additionally, 
where appropriate, EPA aggregates exposures across different routes in 
characterizing risk.
    In estimating and describing the level of concern, the POD is at 
times used differently depending on whether the risk assessment 
addresses dietary or non-dietary exposures. For threshold risks, EPA 
estimates risk in one of two ways. Where EPA has calculated a RfD/PAD, 
risk is estimated by expressing human exposure as a percentage of the 
RfD/PAD. Exposures lower than 100 percent of the RfD/PAD are generally 
not of concern. Alternatively, EPA may express risk by comparing the 
Margin of Exposure (MOE) between estimated human exposure and the POD 
with the acceptable or target MOE. The acceptable or target MOE is the 
product of all applicable safety factors. To calculate the actual MOE 
for a pesticide, estimated human exposure to the pesticide is divided 
into the POD. In contrast to the RfD/PAD approach, the higher the MOE, 
the less risk posed by the pesticide. Accordingly, if the target MOE 
for a pesticide is 100, MOEs equal to or exceeding 100 would generally 
not be of concern.
    As a conceptual matter, the RfD/PAD and MOE approaches are 
fundamentally equivalent. For a given risk and given exposure of a 
pesticide, if exposure to a pesticide were found to be acceptable under 
an RfD/PAD analysis it would also pass under the MOE approach, and 
vice-versa. However, for any specific pesticide, risk assessments for 
different exposure durations or routes may yield different results. 
This is a function not of the choice of the RfD/PAD or MOE approach but 
of the fact that the levels of concern and the levels of exposure may 
differ depending on the duration and route of exposure.
    2. EPA policy on the children's safety factor. As the above brief 
summary of EPA's risk assessment practice indicates, the use of safety 
factors plays

[[Page 56001]]

a critical role in the process. This is true for traditional 10X safety 
factors to account for potential differences between animals and humans 
when relying on studies in animals (inter-species safety factor) and 
potential differences among humans (intra-species safety factor) as 
well as the FQPA 10X children's safety factor.
    In applying the children's safety factor provision, EPA has 
interpreted it as imposing a presumption in favor of applying a 10X 
safety factor to the 10X inter-species and 10X intra-species safety 
factors. (Ref. 9 at 4, 11). Thus, EPA generally refers to the 10X 
children's safety factor as a presumptive or default 10X factor. EPA 
has also made clear, however, that this presumption or default in favor 
of the 10X children' safety is only a presumption. The presumption can 
be overcome if reliable data demonstrate that a different factor is 
safe for children. (Id.). In determining whether a different factor is 
safe for children, EPA focuses on the three factors listed in section 
408(b)(2)(C) - the completeness of the toxicity database, the 
completeness of the exposure database, and potential pre- and post-
natal toxicity. In examining these factors, EPA strives to make sure 
that its choice of a safety factor, based on a weight-of-the-evidence 
evaluation, does not understate the risk to children. (Id. at 24-25, 
35).
    3. EPA policy on cholinesterase inhibition. Carbaryl is a member of 
the N-methyl carbamate class of pesticides. Each member of this class 
shares the ability to inhibit the enzyme, acetylcholinesterase, leading 
to neurotoxicity. N-methyl carbamate neurotoxicity is characterized by 
the rapid onset (often 15-30 minutes) and rapid recovery (within 
hours). Cholinesterase inhibition is a disruption of the normal process 
in the body by which the nervous system chemically communicates with 
muscles and glands. Communication between nerve cells and a target cell 
(i.e., another nerve cell, a muscle fiber, or a gland) is facilitated 
by the chemical, acetylcholine. When a nerve cell is stimulated it 
releases acetylcholine into the synapse (or space) between the nerve 
cell and the target cell. The released acetylcholine binds to receptors 
in the target cell, stimulating the target cell in turn. As EPA has 
explained, ``the end result of the stimulation of cholinergic 
pathway(s) includes, for example, the contraction of smooth (e.g., in 
the gastrointestinal tract) or skeletal muscle, changes in heart rate 
or glandular secretion (e.g., sweat glands) or communication between 
nerve cells in the brain or in the autonomic ganglia of the peripheral 
nervous system.'' (Ref. 10 at 10).
    Acetylcholinesterase (AChE) is an enzyme that breaks down 
acetylcholine and terminates its stimulating action in the synapse 
between nerve cells and target cells. When AChE is inhibited, 
acetylcholine builds up, prolonging the stimulation of the target cell. 
This excessive stimulation potentially results in a broad range of 
adverse effects on many bodily functions including muscle cramping or 
paralysis, excessive glandular secretions, or effects on learning, 
memory, or other behavioral parameters. Depending on the degree of 
inhibition these effects can be serious, even fatal.
    EPA's cholinesterase inhibition policy statement explains EPA's 
approach to evaluating the risks posed by cholinesterase-inhibiting 
pesticides such as carbaryl. (Ref. 10). The policy focuses on three 
types of effects associated with cholinesterase-inhibiting pesticides 
that may be assessed in animal and human toxicological studies: (1) 
physiological and behavioral/functional effects; (2) cholinesterase 
inhibition in the central and peripheral nervous system; and (3) 
cholinesterase inhibition in red blood cells and blood plasma. The 
policy discusses how such data should be integrated in deriving a POD 
for a cholinesterase-inhibiting pesticide.
    EPA uses a weight-of-the-evidence approach to determine the toxic 
effect that will serve as the appropriate POD for a risk assessment for 
AChE inhibiting pesticides, such as carbaryl (Id). The neurotoxicity 
that is associated with these pesticides can occur in both the central 
(brain) and the peripheral nervous system. In its weight-of-the-
evidence analysis, EPA reviews data, such as AChE inhibition data from 
the brain, peripheral tissues and blood (e.g., red blood cell (RBC) or 
plasma), in addition to data on clinical signs and other functional 
effects related to AChE inhibition. Based on these data, EPA selects 
the most appropriate effect on which to regulate; such effects can 
include clinical signs of AChE inhibition, central or peripheral 
nervous tissue measurements of AChE inhibition, or RBC AChE measures 
(Id). Although RBC AChE inhibition is not adverse in itself, it is a 
surrogate for inhibition in peripheral tissues when peripheral data are 
not available. As such, RBC AChE inhibition provides an indirect 
indication of adverse effects on the nervous system (Id.). Measures of 
AChE inhibition in the peripheral nervous system are very rare for N-
methyl carbamate pesticides and no such peripheral data exists for 
carbaryl. For these reasons, other state and national agencies such as 
California, Washington, Canada, the European Union, as well as the 
World Health Organization (WHO), all use blood measures in human health 
risk assessment and/or worker safety monitoring programs.
    4. EPA policy on assessing risk from cumulative effects from 
pesticides with a common mechanism of toxicity. Section 408(b)(2)(D) of 
the FFDCA directs EPA to consider available information on the 
cumulative effects on human health resulting from exposure to multiple 
pesticide chemicals that have a common mechanism of toxicity. EPA 
begins a cumulative risk assessment by identifying a group of 
pesticides, called a common mechanism group, that bring about the same 
toxic effect by a common mechanism of toxicity. Pesticides share a 
common mechanism of toxicity if they act the same way in the body; that 
is, if the same toxic effect occurs in the same organ or tissue by 
essentially the same sequence of major biochemical events.
    There are many steps involved in quantitatively assessing the 
potential human health risk associated with exposure to the N-methyl 
carbamate pesticides. The complex series of evaluations involve hazard 
and dose-response analyses; assessments of food, drinking water, 
residential/non-occupational exposures; combining exposures to produce 
a cumulative risk estimate; and risk characterization. Given the 
complexity of the analyses, EPA's policy is to only conduct a 
cumulative assessment if each of the individual chemicals in the 
assessment has been determined to be ``safe,'' based on aggregate 
exposures only to that individual chemical.

IV. Regulatory History of Carbaryl

A. In General

    Carbaryl is a carbamate insecticide and molluscide that was first 
registered in 1959 for use on cotton. Carbaryl has many trade names, 
but is most commonly known as Sevin[reg]. At the time carbaryl was 
assessed for purposes of reregistration, carbaryl was registered for 
use on over 400 agricultural and non-agricultural use sites, and there 
were more than 140 tolerances for carbaryl in the Code of Federal 
Regulations (40 CFR 180.169). The primary risk of concern from exposure 
to carbaryl is acute neurotoxic effects. Carbaryl is a member of the N-
methyl carbamate class of pesticides. This group shares a common 
mechanism of toxicity; namely, the ability to inhibit

[[Page 56002]]

the enzyme acetylcholinesterase (AChE) through carbamylation of the 
active site. Pesticides included is this group, other than carbaryl, 
are aldicarb, carbofuran, formetanate hydrochloride, methiocarb, 
methomyl, oxamyl, pirimicarb, propoxur, and thiodicarb.

B. FFDCA Tolerance Reassessment and FIFRA Pesticide Reregistration

    1. Interim reregistration eligibility decision. EPA completed an 
interim reregistration eligibility decision (IRED) for carbaryl on June 
30, 2003 (2003 IRED). The decision on reregistration was treated as 
interim because of carbaryl's membership in the N-methyl carbamate 
cumulative group. When EPA determines that a pesticide shares a common 
mechanism of toxicity with other substances, EPA cannot complete either 
the assessment or reassessment of a tolerance or a registration or 
reregistration determination until it has assessed available 
information regarding exposures to the other substances. For these 
pesticides, EPA's practice is to issue an IRED pending completion of 
the tolerance reassessment activities. An IRED memorializes EPA's 
determination on a narrowly defined issue: Whether a given active 
ingredient alone is eligible for reregistration under FIFRA and 
tolerance reassessment under the FFDCA, pending a cumulative assessment 
for pesticides sharing a common mechanism of toxicity.
    Although EPA found in the 2003 IRED that carbaryl dietary exposures 
from food and water were below the relevant safe doses (i.e., the acute 
PAD (aPAD) and chronic PAD (cPAD)), EPA concluded that numerous 
residential uses posed a risk of concern. Accordingly, the 2003 IRED 
specified various changes to the carbaryl registration to address these 
risks, including: Canceling liquid broadcast applications to home lawns 
pending EPA review of pharmacokinetic data to refine post-application 
risk estimates; repackaging home garden/ornamental dust products in 
ready-to-use shaker can containers, with no more than 0.05 lbs. active 
ingredient (ai) per container; canceling the following uses and 
application methods -- all pet uses (dusts and liquids) except collars, 
aerosol products for various uses, belly grinder applications of 
granular and bait products for lawns, hand applications of granular, 
and bait products for ornamentals and gardens.
    2. Amended interim reregistration eligibility decision. The Agency 
amended the 2003 IRED on October 22, 2004 (2004 Amended IRED), and 
published a formal Notice of Availability for the document, which 
provided for a 60-day public comment period. EPA received numerous 
comments on the carbaryl 2004 Amended IRED, including the NRDC petition 
requesting that EPA cancel all carbaryl registrations and revoke all 
tolerances. The mitigation detailed in the 2004 Amended IRED for 
residential uses included limiting applications of liquid formulations 
to residential turf areas to spot treatment only; requiring dust 
formulations to be packaged in a ready-to-use container containing no 
more than 0.05 lbs ai/container; and cancelation of all pet uses, 
except for carbaryl treated pet collars. On March 9, 2005, EPA issued a 
cancellation order for the liquid broadcast use of carbaryl on 
residential turf to address post-application risk to toddlers. (Ref. 
11). In March 2005, EPA also issued generic and product-specific data 
call-ins (DCIs) for carbaryl. The carbaryl generic DCI required several 
studies of the active ingredient carbaryl, including additional 
toxicology, worker exposure monitoring, and environmental fate data. 
The product-specific DCI required acute toxicity and product chemistry 
data for all pesticide products containing carbaryl; these data are 
being used for product labeling. EPA has received numerous studies in 
response to these DCIs, and, where appropriate, these studies were 
considered in the tolerance reassessment.
    In response to the DCIs, many carbaryl registrants chose to 
voluntarily cancel their carbaryl products, rather than revise their 
labels or conduct studies to support these products. EPA published a 
notice of receipt of these requests in the Federal Register on October 
28, 2005 (70 FR 62112), followed by a cancellation order issued on July 
3, 2006. One technical registrant, Burlington Scientific, chose to 
cancel their technical product, leaving Bayer CropScience (Bayer) as 
the sole technical registrant for carbaryl. Approximately two-thirds of 
all of the carbaryl products registered at the time of the 2003 IRED 
have been canceled through this process.
    Bayer subsequently requested that all of their carbaryl 
registrations be amended to delete the following uses: carbaryl use in 
or on pea and bean, succulent shelled (subgroup 6B); millet; wheat; 
pre-plant root dip for sweet potato; pre-plant root dip/drench for 
nursery stocks, vegetable transplants, bedding plants, and foliage 
plants; use of granular formulations on leafy vegetables (except 
Brassica); ultra low volume (ULV) application for adult mosquito 
control; and dust applications in agriculture. EPA notified all 
affected registrants that these uses and application methods must be 
deleted from their carbaryl product labels. EPA identified 34 product 
labels from 14 registrants (other than Bayer) bearing these end uses. 
All of these registrants requested that their affected carbaryl product 
registrations be amended to delete these uses. EPA published Notices of 
receipt of these requests from Bayer and all 14 registrants in the 
Federal Register on August 20, 2008 and October 15, 2008. On March 18, 
2009, the Agency published an order granting the requests to delete 
uses (74 FR 11553). Most recently, in a letter dated September 30, 
2009, Wellmark International submitted a request to voluntarily cancel 
its pet collar registrations pursuant to section 6(f) of FIFRA (74 FR 
54045, October 21, 2009). These are the only carbaryl pet collar 
registrations and the last remaining pet product registrations for 
carbaryl. EPA issued its final order cancelling carbaryl registrations 
for pet collar uses on December 16, 2009. (74 FR 66642, December 16, 
2009).
    3. Reregistration eligibility decision. As noted, the 
reregistration eligibility decision had to remain interim in nature 
until the N-methyl carbamate cumulative risk assessment was completed. 
That assessment was issued on September 26, 2007, and EPA concluded 
that the cumulative risks associated with the N-methyl carbamate 
pesticides meet the safety standard set forth in section 408(b)(2) of 
the FFDCA, provided that the mitigation specified in the N-methyl 
carbamate cumulative risk assessment is implemented, such as 
cancellation of all uses of carbofuran, termination of methomyl use on 
grapes, etc. EPA has therefore terminated the tolerance reassessment 
process under 408(q) of the FFDCA. (See Ref. 12 for additional 
information).
    In conjunction with the N-methyl carbamate cumulative risk 
assessment, EPA completed a RED for carbaryl on September 24, 2007 (the 
RED was issued on October 17, 2007 with a formal Notice of Availability 
in the Federal Register (72 FR 58844)). (Ref. 12). In addition to 
relying on the N-methyl carbamate cumulative risk assessment to 
determine that the cumulative effects from exposure to all N-methyl 
carbamate residues, including carbaryl, was safe, the carbaryl RED 
relied upon the revised assessments and the mitigation that had already 
been implemented (e.g., cancellation of pet uses except for collars). 
Additionally, the RED included additional mitigation with respect to 
granular turf products for residential use; namely, that product labels 
direct users to water the product in immediately after application. EPA

[[Page 56003]]

subsequently completed an addendum to the carbaryl RED, dated August 
25, 2008, which incorporated the results of a revised occupational risk 
assessment and modified mitigation measures for the protection of 
workers. The Agency issued a Notice of Availability for the RED 
addendum in the October 29, 2008 Federal Register (73 FR 64317).
    4. Risk assessment issues with the IRED and RED relevant to NRDC 
petition--a. selection of POD. When deriving Points of Departure and 
assigning uncertainty/safety factors in risk assessment, EPA looks at 
all the appropriate data available at a given time. In cases when new 
data become available improving the quality of the overall 
toxicological database, it is typical practice to re-consider previous 
decisions of the most appropriate Point(s) of Departure and uncertainty 
factors. Specific to carbaryl, Points of Departures and uncertainty/
safety factors have changed over time as new data have become available 
to fill data gaps, provide additional information on existing data, and 
describe the effects in juvenile animals.
    For the 2003 IRED and 2004 Amended IRED, the POD for acute exposure 
was from a developmental neurotoxicity (DNT) study. The POD used for 
risk assessment was 1 milligrams/kilogram/day (mg/kg/day) based upon 
the results of the DNT study. In the DNT study the LOAEL was 10 mg/kg/
day based upon functional observational changes (pinpoint pupils, 
tremors, and gait abnormalities). Also occurring in this study were 
morphometric changes in the brain with a LOAEL of 10 mg/kg/day: 
bilateral decrease in the size of the forebrain in adult males; a 
bilateral decrease in the length of the cerebella in female pups; and a 
bilateral increase in the length of the cerebella in female adults. A 
NOAEL for these effects was not identified in the study because a 
morphometric analysis was conducted in only the control and high-dose 
groups (10 mg/kg/day), but not in low-dose (0.1 mg/kg/day) or mid-dose 
(1.0 mg/kg/day) groups. Initially, upon review of the data, EPA had 
requested that morphometric analysis of the low-dose and mid-dose 
groups be conducted, but this was not possible because the brain 
tissues had dried during the preservation process. Nonetheless, EPA 
determined that the developmental NOAEL was likely 1 mg/kg/day. This 
conclusion was based on the finding that the morphometric changes, 
although statistically significant, were minimal in nature and, 
therefore, judged not likely to be present at the mid-dose of 1 mg/kg/
day. (Refs. 13, 14, and 15).
    Subsequently, in November of 2006, OPP received data from a 
carbaryl comparative cholinesterase assay study (CCA study) performed 
by EPA's Office of Research and Development. CCA studies are specially 
designed toxicity studies that evaluate comparative sensitivity in 
adult and juvenile rats with respect to inhibition of cholinesterase 
activity. In the case of the carbaryl CCA study, the juvenile rats were 
aged post-natal day 11 and 17 (PND11 and PND17).
    In the carbaryl CCA, a time course study was first conducted to 
determine the time to peak ChE effects followed by a dose-response 
study where rats were dosed by oral gavage with corn oil or 3, 7.5, 15, 
or 30 mg carbaryl/kg body weight. All ages received the same dose so as 
to better compare the effects across ages. The dose was given at 2 ml/
kg. Therefore, the dosing solutions were 0, 1.5, 3.75, 7.5, or 15 mg/
ml. In 2007, EPA conducted a BMD analysis for the carbaryl CCA study, 
using the same modeling methodology used in the N-methyl carbamate 
cumulative risk assessment. This BMD analysis demonstrated sensitivity 
of PND11 and PND17 pups compared to adult ORD ChE data. Previously, in 
2005 and in support of the N-methyl carbamate cumulative risk 
assessment, the Agency also conducted a BMD analysis of brain and RBC 
cholinesterase inhibition in rat oral toxicity studies for adults. 
(Ref. 16, see also Refs. 17 and 18). The BMD10 is the 
estimated benchmark doses that results in 10% cholinesterase inhibition 
(a level generally regarded as not an adverse effect), and the 
BMDL10 is the lower 95% confidence interval on the 
BMD10, for the data evaluated. Generally, the 
BMD10 is used to compare across compartments and across ages 
but the BMDL10 is used as the POD. The results of the study 
are presented in the following table in terms of the BMD10 
and BMDL10:

----------------------------------------------------------------------------------------------------------------
                                                           Brain (mg/kg)                   RBC (mg/kg )
                       Age                       ---------------------------------------------------------------
                                                       BMD10          BMDL10            BMD           BMDL10
----------------------------------------------------------------------------------------------------------------
PND11                                                       1.46            1.14            1.11            0.78
----------------------------------------------------------------------------------------------------------------
PND17                                                       3.00            2.37            1.41            1.05
----------------------------------------------------------------------------------------------------------------
Adults                                                      2.63            2.03            0.96            0.73
----------------------------------------------------------------------------------------------------------------

    As the table shows, juvenile 11-day old (PND11) pups were 1.8 times 
more sensitive to inhibition of brain cholinesterase than adult rats in 
terms of BMDs. The BMD analyses show that the brain BMD for pups is 
protective of adults since the pup BMD values are lower than adult 
values. For the red blood cell cholinesterase (RBC ChE) compartment, 
the RBC BMD10 in PND11 pups is similar to that in adults. 
Although the RBC BMDL10 for PND11 pups is numerically lower 
(0.8 mg/kg) than the BMDL10 for PND11 brain AChE inhibition 
(1.1 mg/kg), the magnitude of this difference is not biologically 
meaningful, particularly in light of the similarity in 
BMD10s, and considering the higher variability typically 
seen in RBC measurements relative to brain. Brain represents the target 
tissue for the N-methyl carbamates as opposed to using a surrogate 
measure (RBC) and the brain BMDL10 of 1.1 mg/kg would be 
protective of both central nervous system and peripheral nervous system 
effects. (Refs. 17 and 18).
    For the carbaryl risk assessment, the BMDL10 for 
inhibition of brain cholinesterase in PND11 juveniles from the CCA 
study was chosen as the most sensitive and appropriate POD for 
calculating a safe dose instead of using an extrapolated NOAEL from the 
DNT study. Several factors were critical to that determination. First, 
the CCA study is considered a sentinel study for the N-methyl 
carbamates as it evaluates the most sensitive endpoint (cholinesterase 
inhibition) in the most sensitive age group (PND11) at the time of peak 
effect. For each N-methyl carbamate with a valid CCA study, this study 
is being used in the risk assessment to inform the children's safety 
factor or the POD. EPA has high confidence in the quality of the data 
from the carbaryl study because it used a broad range of doses and used 
the radiometric method of measuring AChE inhibition. (Ref. 19). The 
radiometric method for assaying

[[Page 56004]]

ACHe inhibition provides the most appropriate method for measuring 
cholinesterase inhibition due to N-methyl carbamate exposure because 
factors (i.e., assay temperature, dilution, and incubation time) which 
promote reversibility are minimized.
    Second, gavage studies, such as the CCA study, are the preferred 
and most sensitive studies for carbaryl. The toxicity profile of 
carbaryl and other N-methyl carbamates is characterized by a rapid 
onset of toxicity with a peak time of effect around 15 to 60 minutes 
and rapid recovery (typical half-lives in adult rats are 1 to 2 hours). 
This pattern of toxicity is shown in Figure 1 for carbaryl.
[GRAPHIC] [TIFF OMITTED] TR15SE10.020

    With N-methyl carbamates, due to rapid recovery, toxicity does not 
accumulate in juveniles or adults with repeated exposures. As such, EPA 
is most concerned about acute effects, particularly those which occur 
at the peak time of effect. The Agency has found for these pesticides 
that acute studies, particularly via gavage administration, provide the 
most sensitive effects (i.e., more health protective) for risk 
assessment. Specifically, acute gavage studies provide more sensitive 
effects than studies administered in the diet, even studies of much 
longer durations. For example, the NOAEL and LOAEL for RBC AChE 
inhibition in the carbaryl dietary 2-year rat chronic/carcinogenicity 
study are 10/12\1\ mg/kg/day and 60.2/78.6 mg/kg/day in adult rats, 
whereas the BMD10/BMDL10 for RBC AChE inhibition 
in adult rats in acute gavage studies are 0.96 and 0.73 mg/kg. Based on 
this comparison, the acute gavage study provides toxicity values almost 
tenfold more sensitive than in the 2-year feeding study.
---------------------------------------------------------------------------

    \1\ Two values are provided for males/females.
---------------------------------------------------------------------------

    This pattern of toxicity is somewhat unique to this class of 
pesticides and can be attributed to the pharmacokinetic and 
pharmacodynamic properties of N-methyl carbamates, like carbaryl. The 
parent active ingredient, carbaryl, is the toxicologically active 
compound. As such, no metabolic activation is required; instead, 
metabolism results in detoxification of carbaryl. As evidenced by the 
rapid onset of toxicity, these pesticides are rapidly absorbed, 
distributed, and cleared from the body.
    For this class of pesticides, neurotoxicity is correlated to peak 
concentrations of carbaryl. Specifically, brain tissue levels and 
inhibition of brain AChE at the time of peak effect are highly 
correlated. In dietary administration studies like the 2-year study and 
the DNT study, rats are exposed to carbaryl over several hours of 
feeding. This is in contrast to a bolus dose in gavage studies where 
the entire dose is given at one time. In the dietary studies, the total 
administered dose of carbaryl consumed may be equal or even higher than 
the gavage dose. However, it is the internal dose of carbaryl at the 
target tissues which is related to the magnitude to toxicity. In the 
dietary studies, due to the rapid metabolism and clearance, carbaryl 
does not reach a peak level like that in gavage studies at the target 
tissues and thus the degree of toxicity in dietary studies is far less 
than that for gavage studies. As a result, acute gavage studies tend to 
be far more sensitive than dietary studies for N-methyl carbamates. 
This is the case for carbaryl as shown by the high quality and 
sensitive data from the CCA study.
    Finally, the changes in brain morphometrics (10 mg/kg) from the DNT 
study originally used in the POD derivation were determined to be a 
marginal effect not consistently seen in carbarmate pesticides. (See 
Unit IV.B.4.b. for a full discussion of EPA's review of the DNT study.) 
Although a 10X uncertainty factor was originally applied to the 
marginal brain morphometric endpoint, the real NOAEL is likely greater 
than 1 mg/kg and less than 10 mg/kg.
    In any event, the extrapolated NOAEL from the DNT study is 
essentially

[[Page 56005]]

equivalent to the BMDL10 for PND11 juveniles in the CCA 
study (i.e., 1 mg/kg/day as compared to 1.1 mg/kg/day). As explained 
below, if the LOAEL from the DNT was used in calculating a safe dose, 
EPA would retain a children's safety factor of no greater than 10X due 
to the lack of a NOAEL in that study. Retention of a children's safety 
factor of 10X would make the extrapolated NOAEL for the DNT study 
essentially equivalent to the BMDL10 for PND11 juveniles in 
the CCA study (i.e., 1 mg/kg/day as compared to 1.1 mg/kg/day).
    b. Children's safety factor. With respect to the children's safety 
factor, in preliminary reviews undertaken in 1999 and 2001, EPA 
initially retained the full 10X safety factor for carbaryl. The reasons 
for retaining the 10X children's safety factor were that EPA was 
missing a two-generation reproduction study for carbaryl and the DNT 
study showed changes in brain morphometric measurements of the 
offspring which raised concerns. The data from the DNT study showed 
that for the first generation pups, there were no treatment-related 
effects on pup weight, pup survival indices, developmental landmarks 
(tooth eruption and eye opening), Functional Observational Battery 
(FOB) measurements or motor activity assessments. There were also no 
treatment related effects on brain weight and gross or microscopic 
pathology. There were, however, changes noted in brain morphometric 
measurements at the high dose (10 mg/kg/day): Bilateral decrease in the 
size of the forebrain in adult males; a bilateral decrease in the 
length of the cerebella in female pups; and a bilateral increase in the 
length of the cerebella in female adults. EPA requested that a 
morphometric analysis of the low-dose and mid-dose groups be conducted, 
but this was not possible because brain samples had not been prepared 
for measurement and the tissues had dried during the preservation 
process. At the time, EPA found these changes at the high dose to be 
significant. (See generally Refs. 20, 21, 22, 23, 24, 25 and 26).
    When new information became available in 2002, EPA removed the 10X 
safety factor for acute dietary and short-and intermediate-term 
exposures. (Refs. 13, 14 and 15). Not only did EPA receive a new two-
generation reproduction study (and therefore no longer had any data 
gaps) but EPA also obtained new brain morphometric measurements from 
the DNT study for the control and high-dose groups. The new 
measurements demonstrated that even at the high dose, the morphometric 
changes, although statistically significant, were minimal in nature. 
This is consistent with the DNT study results for other N-methyl 
carbamates (aldicarb and carbofuran), which did not show any changes in 
morphometrics. In addition, the DNTs available for all three N-methyl 
carbamates have not shown any long-term effects, including effects on 
behavior. The Agency is also not aware of any literature studies that 
have shown any changes in brain histopathology following N-methyl 
carbamate exposure to animals of any age. Based on this information, 
EPA concluded that the brain morphometic effects were not likely to be 
present at the mid-dose. (Refs. 13, 14 and 15). Because the 
developmental effects in the DNT were now well-characterized and the 
evidence strongly indicated that no brain morphometric changes would 
have been present at the mid-dose (1 mg/kg/day), EPA determined that 
the children's safety factor was not needed. In addition, there were no 
concerns or residual uncertainties for pre- and/or postnatal toxicity 
from other carbaryl development studies.
    After EPA received the CCA study in 2006, it modified its decision 
on the children's safety factor slightly. As explained above, the 
BMDL10 for PND11 juveniles from the CCA study was chosen for 
the POD in calculating a safe dose. Because (1) EPA had a complete data 
set for carbaryl including high quality data comparing the relative 
sensitivity of adults and the young, (2) the effects in the young had 
been well-characterized, and (3) the most sensitive effect in the young 
(the BMDL10 from the CCA study) was being used to calculate 
the safe dose (i.e., the BMDL10 was divided by inter- and 
intra-species safety factors), EPA determined that a children's safety 
factor was not needed for risk assessments based on the CCA study. 
Where carbaryl assessments relied on other data not involving the 
testing of juveniles, EPA retained a children's safety factor of 1.8X 
reflecting the degree of sensitivity of the young observed in the CCA 
study.
    c. Calculation of safe dose/aPAD for carbaryl. For dietary risks, 
EPA calculated the aPAD by dividing the dietary POD (the 
BMDL10 for PND11 juveniles in the CCA study) by the inter-
species and intra-species safety factors (100X) to yield a value of 
0.01 mg/kg. For dermal risks, instead of calculating an aPAD, EPA 
assessed risk under a MOE approach. The acceptable or target MOE was 
calculated using a POD of 86 mg/kg. The POD was obtained by multiplying 
the BMDL10 of 30.56 mg/kg from the dermal toxicity study by 
2.8, because in an in vitro dermal absorption study, rat skin was 2.8 
times more permeable than human skin to carbaryl. The target MOE for 
risk assessment is 100 for adults because the inter-species and intra-
species safety factors total 100X. The target MOE for risk assessment 
for infants and children is 180 because, in addition to the 100X, the 
children's safety factor is 1.8X.

V. NRDC Petitions Regarding Carbaryl

    In the underlying petition, NRDC requested, among other things, 
that EPA cancel all carbaryl registrations and revoke all carbaryl 
tolerances. (Ref. 2). NRDC's January 10, 2005 petition was submitted in 
the form of comments on and requests for changes to the Carbaryl 
Interim Reregistration Eligibility Decision published in the Federal 
Register on October 27, 2004, 70 FR 62663. Nonetheless, in the 
introduction to the comments, NRDC included a statement that NRDC was 
also petitioning the Agency to revoke all carbaryl tolerances. Among 
other things, NRDC raised issues with the dietary assessment, and in 
particular, EPA's drinking water assessment that supported the 2004 
IRED decision. NRDC also raised concerns about the data surrounding 
EPA's selection of a children's safety factor. NRDC raised other safety 
factor issues, particularly as they relate to EPA use of the DNT study. 
NRDC's petition also included generic disagreements with how EPA 
conducts its assessments.
    Subsequently, as part of its comments on the N-methyl carbamate 
cumulative assessment dated November 26, 2007, NRDC requested that EPA 
cancel all carbaryl pet collar registrations. (Ref. 3). The basis for 
NRDC's petition to cancel all pet collar registrations rested on issues 
related to EPA's assessment of cumulative effects under the FFDCA. In 
addition, NRDC incorporated by reference its earlier petition to revoke 
all carbaryl tolerances. Accordingly, EPA addressed the exposure issues 
raised in the subsequent pet collar petition as part of its response to 
the earlier petition to revoke all carbaryl tolerances.

VI. EPA's Response to the Petitions to Revoke Carbaryl Tolerances

    On October 29, 2008, EPA denied NRDC's petition to revoke all 
pesticide tolerances for carbaryl under section 408(d) of the FFDCA. 
(73 FR 64229). EPA's Order also constituted a response to NRDC's 
petition dated November 26, 2007, to cancel carbaryl pet collar 
registrations submitted as part of NRDC's comments on the N-methyl 
carbamate cumulative assessment. Again, EPA's response to NRDC's 
petition to cancel pet collar registrations was addressed in that Order 
because the

[[Page 56006]]

basis for the petition to cancel pet collars rested on issues related 
to EPA's assessment of cumulative effects under the FFDCA.

VII. NRDC's Objections and Requests for Hearing

    On December 28, 2008, NRDC filed, pursuant to FFDCA section 
408(g)(2), objections to EPA's denial of its tolerance revocation 
petition and requested a hearing on those objections. As indicated 
above, NRDC's objections and requests for hearing raise two main 
claims: (1) that EPA lacks reliable data to reduce the default tenfold 
safety factor and (2) that EPA's exposure assessment for carbaryl is 
flawed and underestimates the exposure to children from pet collar 
uses.
    NRDC asserts that EPA failed to consider the available 
developmental neurotoxicity data and, therefore, unlawfully lowered the 
10X children's safety factor. Specifically, NRDC argues that the DNT 
study showed adverse developmental abnormalities in juvenile test 
animals at doses that had no effect on adult test animals. According to 
NRDC, this finding alone supports a full 10X children's safety factor. 
In addition, NRDC asserts that the DNT study did not identify a no-
effect level in juvenile animals, supporting a further 3X safety 
factor. Thus, NRDC argues that EPA should have applied a 30X safety 
factor (10X for age sensitivity and 3X for failure to identify a no-
effect level) to the end-point from the DNT to establish a final POD. 
According to NRDC, to do otherwise is ``arbitrary and capricious, and 
contrary to the law.'' (Ref. 1 at 8.)
    NRDC also asserts that EPA's exposure assessment underestimates 
exposure to children from pet collar uses. NRDC further asserts that 
EPA relied on flawed studies and data, and, therefore, the Agency's 
determination that tolerances are safe is improper. Among other things, 
NRDC argues that at the time of EPA's determination, data on exposure 
from use of carbaryl in pet collars required by a 2005 DCI had not been 
submitted and that without the data EPA's decision is ``arbitrary and 
capricious and contrary to law.'' (Ref. 1 at 9).
    EPA regulations make clear that to be considered by the 
Administrator, a request for an evidentiary hearing must meet certain 
criteria. (40 CFR 178.27). One such criteria is that the request must 
include a copy of any report, article, survey, or other written 
document (or the pertinent pages thereof) upon which the objector 
relies to justify an evidentiary hearing, unless the document is an EPA 
document that is routinely available to any member of the public.
    In support of its request for a hearing, NRDC submitted the 
following documents as evidence that a hearing is appropriate: (1) 
Poisons on Pets Health Hazards from Flea and Tick Products, David 
Wallinga, MD., MPA and Linda Greer, Ph.D (NRDC, November 2000); and (2) 
Opportunities to Improve Data Quality and Children's Health through the 
Food Quality Protection Act (EPA- OIG Evaluation Report; Report 
 2006-P-00009) (January 10, 2006).
    In addition, NRDC cited to the following EPA documents: (1) Amended 
Carbaryl Reregistration Eligibility Decision (RED) (August, 2008); (2) 
Carbaryl RED (September, 2007); (3) Carbaryl Interim RED (IRED) (June, 
2003); Organophosphate Cumulative Risk Assessment (2006); and, Revised 
N-Methyl Carbamate Cumulative Risk Assessment [DRAFT] (2007).

VIII. Response to Objections and Requests for Hearing

A. Overview

    EPA denies NRDC's objections as well as its hearing requests. 
NRDC's hearing requests fail to meet the statutory and regulatory 
requirements for holding a hearing. NRDC has failed to proffer evidence 
on its hearing requests which would, if established, resolve one or 
more issues in its favor. Most significant, however, is that NRDC's 
claims do not present genuine and substantial issues of fact. On the 
merits, NRDC's objections with respect to the use of particular studies 
to establish an appropriate POD as well as appropriate safety factors 
are denied on scientific, policy, and legal grounds. Finally, NRDC's 
objection with respect to EPA exposure assessment of pet collars is 
denied as moot because EPA has already issued a cancellation order 
under section 6(f) of FIFRA for the last remaining carbaryl pet collar 
product registration.
    The remainder of this Unit is organized in the following manner. 
Unit VIII.B. describes in greater detail the requirements pertaining to 
when it is appropriate to grant a hearing request. Unit VIII.C. 
examines the evidence proffered by NRDC in support of its hearing 
requests. Unit VIII.D. provides EPA's response to the NRDC's objections 
and hearing requests.

B. The Standard for Granting an Evidentiary Hearing

    EPA has established regulations governing objections to tolerance 
rulemakings and tolerance petition denials and requests for hearings on 
those objections. (40 CFR part 178; 55 FR 50291, December 5, 1990). 
Those regulations prescribe both the form and content of hearing 
requests and the standard under which EPA is to evaluate requests for 
an evidentiary hearing.
    As a threshold matter, EPA's regulations limit the issues that can 
be raised in any hearing as well as in objections. In general, the 
provisions of FFDCA section 408(g) establish an informal rulemaking 
process that is governed by section 553 of the Administrative Procedure 
Act (APA) and the case law interpreting these requirements, except to 
the extent that section 408 provides otherwise. For example, section 
408(d) allows the Agency to proceed to a final rule after publication 
of a submitted petition, rather than requiring publication of a 
proposal. In this regard, it is well established that the failure to 
raise factual or legal issues during the comment period of a rulemaking 
constitutes waiver of the issues in further proceedings. See generally, 
74 FR 59608, 59624-59629, November 18, 2009.
    The fact that FFDCA section 408 in certain limited circumstances 
supplements the informal rulemaking with a hearing does not 
fundamentally alter the requirements applicable to informal 
rulemakings. Nor does it convert this into a formal rulemaking, subject 
to the exception in section 553 of the APA. Section 408 of the FFDCA 
establishes a unique statutory structure with multiple procedural 
stages, and delegates to EPA the discretion to determine the 
implementation that best achieves the statutory objectives. 
Accordingly, EPA interprets the notice and comment rulemaking portion 
of the FFDCA section 408 process as an integral part of the FFDCA 
process, inextricably linked to the administrative hearing. The point 
of the rulemaking is to resolve the issues that can be resolved, and to 
identify and narrow any remaining issues for adjudication. 
Consequently, the administrative hearing does not represent an 
unlimited opportunity to supplement the record, particularly with 
information that was available during the comment period, but that 
commenters have chosen to withhold.
    EPA has consistently interpreted FFDCA section 408 in this fashion 
since the 1996 amendments. For example, EPA previously ruled that a 
petitioner could not raise new issues in filing objections to EPA's 
denial of its original petition. (See 72 FR 39318, 39324, July 18, 
2007.) (EPA's tolerance revocation procedures ``are not some sort of 
`game,'

[[Page 56007]]

whereby a party may petition to revoke a tolerance on one ground, and 
then, after the petition is denied, file objections to the denial based 
on an entirely new ground not relied upon by EPA in denying the 
petition.''). EPA reasoned that new issues were not cognizable because 
they are ``not an objection to the `provisions of the ... order 
[denying the petition]' '' (Id.). Similarly, EPA denied a request for a 
hearing because the requestor had failed in their original petition to 
raise the claim asserted in their objection. (73 FR 42683, 42696, July 
23, 2008). EPA noted that although requestor did argue in its petition 
that EPA cannot make a safety finding without completing the endocrine 
screening program under FFDCA section 408(p), it did not assert claims 
regarding the endocrine data and the children's safety factor. Citing 
its previous decision, EPA denied the objections and hearing requests 
as to the children's safety factor. (Id.). In that same decision, EPA 
also denied a number of hearing requests on the ground that the 
requestor failed to proffer supporting evidence; EPA opined that a 
failure to offer evidence at an earlier stage of the administrative 
proceeding could not be cured by suddenly submitting such evidence with 
a hearing request. See 73 FR 42710 (``Presumably Congress created a 
multi-stage administrative process for resolution of tolerance 
petitions to give EPA the opportunity in the first stage of the 
proceedings to resolve factual issues, where possible, through a 
notice-and-comment process, prior to requiring EPA to hold a full 
evidentiary hearing, which can involve a substantial investment of 
resources by all parties taking part .... Accordingly, if a party were 
to withhold evidence from the first stage of a tolerance petition 
proceeding and only produce it as part of a request for a hearing on an 
objection, EPA might very likely determine that such an untimely 
submission of supporting evidence constituted an amendment to the 
original petition requiring a return to the first stage of the 
administrative proceeding (if, consideration of information that was 
previously available is appropriate at all'')). Finally, in a recent 
decision, the United States Court of Appeals for the District of 
Columbia Circuit upheld this interpretation of section 408. See Nat'l 
Corn Growers Assn. v. EPA, No 09-1284, slip op. at 9-10 (C.A.D.C. July 
23, 2010)(``We agree with EPA....[T]he comment period would be 
redundant and superfluous is the same concerns could be raised at the 
objections stage.'')
    Nonetheless, EPA does not interpret the statute and regulations to 
preclude the submission of any new information as part of the 
objections phase. Such a position would in fact be inconsistent with 
EPA's own regulations and past practice, which require that in order to 
support a hearing request, a party submit more than ``mere allegations 
or denials.'' (40 CFR 178.32(b)(2)). Rather, EPA's interpretation in 
this regard is analogous to the determination of whether a final rule 
is the logical outgrowth of the proposal and the comments. Ultimately, 
EPA's policy is merely that the objections phase does not present an 
opportunity for parties to begin the process entirely anew, by raising 
issues or information that could have been fairly presented as comments 
on the proposed rule or Notice of Filing of the pesticide petition. Nor 
is the statute's additional procedural step an excuse to withhold 
information that was clearly available at the time of the rulemaking.
    As to the form and content of a hearing request, the regulations 
specify that a hearing request must include: (1) a statement of the 
factual issues on which a hearing is requested and the requestor's 
contentions on those issues; (2) a copy of any report, article, or 
other written document ``upon which the objector relies to justify an 
evidentiary hearing;'' and (3) a summary of any other evidence relied 
upon to justify a hearing. (40 CFR 178.27).
    The standard for granting a hearing request is set forth in 40 CFR 
178.32. That section provides that a hearing will be granted if EPA 
determines that the ``material submitted'' shows all of the following:
     (1) There is a genuine and substantial issue of fact for 
resolution at a hearing. An evidentiary hearing will not be granted on 
issues of policy or law.
     (2) There is a reasonable possibility that available evidence 
identified by the requestor would, if established, resolve one or more 
of such issues in favor of the requestor, taking into account 
uncontested claims or facts to the contrary. An evidentiary hearing 
will not be granted on the basis of mere allegations, denials, or 
general descriptions of positions and contentions, nor if the 
Administrator concludes that the data and information submitted, even 
if accurate, would be insufficient to justify the factual determination 
urged.
     (3) Resolution of the factual issue(s) in the manner sought by the 
person requesting the hearing would be adequate to justify the action 
requested. An evidentiary hearing will not be granted on factual issues 
that are not determinative with respect to the action requested. For 
example, a hearing will not be granted if the Administrator concludes 
that the action would be the same even if the factual issue were 
resolved in the manner sought.
(40 CFR 178.32(b)).
    This provision essentially imposes four requirements upon a hearing 
requestor. First, the requestor must show it is raising a question of 
fact, not one of law or policy. Hearings are for resolving factual 
issues not for debating law or policy questions. Second, the requestor 
must demonstrate that there is a genuine dispute as to the issue of 
fact. If the facts are undisputed or the record is clear that no 
genuine dispute exists, there is no need for a hearing. Third, the 
requestor must show that the disputed factual question is material, 
i.e., that it is outcome determinative with regard to the relief 
requested in the objections. Finally, the requestor must make a 
sufficient evidentiary proffer to demonstrate that there is a 
reasonable possibility that the issue could be resolved in favor of the 
requestor. Hearings are for the purpose of providing objectors with an 
opportunity to present evidence supporting their objections; as the 
regulation states, hearings will not be granted on the basis of ``mere 
allegations, denials, or general descriptions of positions or 
contentions.'' (40 CFR 178.32(b)(2)).
    EPA's hearing request requirements are based heavily on FDA 
regulations establishing similar requirements for hearing requests 
filed under other provisions of the FFDCA. (53 FR 41126, 41129, October 
19, 1988). FDA pioneered the use of summary judgment-type procedures to 
limit hearings to disputed material factual issues and thereby conserve 
agency resources. FDA's use of such procedures was upheld by the 
Supreme Court in 1972, (Weinberger v. Hynson, Westcott & Dunning, Inc., 
412 U.S. 609 (1973)), and, in 1975, FDA promulgated generic regulations 
establishing the standard for evaluating hearing requests. (40 FR 
22950, May 27, 1975). It is these regulations upon which EPA relied in 
promulgating its hearing regulations in 1990.
    Unlike EPA, FDA has had numerous occasions to apply its regulations 
on hearing requests. FDA's summary of the thrust of its regulations, 
which has been repeatedly published in the Federal Register in orders 
ruling on hearing requests over the last 26 years, is

[[Page 56008]]

instructive on the proper interpretation of the regulatory 
requirements. That summary states:
     A party seeking a hearing is required to meet a `threshold burden 
of tendering evidence suggesting the need for a hearing.' [] An 
allegation that a hearing is necessary to sharpen the issues' or fully 
develop the facts' does not meet this test. If a hearing request fails 
to identify any evidence that would be the subject of a hearing, there 
is no point in holding one.
     A hearing request must not only contain evidence, but that 
evidence should raise a material issue of fact concerning which a 
meaningful hearing might be held. [] FDA need not grant a hearing in 
each case where an objection submits additional information or posits a 
novel interpretation of existing information. [] Stated another way, a 
hearing is justified only if the objections are made in good faith and 
if they ``draw in question in a material way the underpinnings of the 
regulation at issue.'' Finally, courts have uniformly recognized that a 
hearing need not be held to resolve questions of law or policy.
(49 FR 6672, 6673, February 22, 1984; 72 FR 39557, 39558, July 19, 
2007) (citations omitted)). EPA has been guided by FDA's application of 
its regulations in this proceeding. Congress confirmed EPA's authority 
to use summary judgment-type procedures with hearing requests when it 
amended FFDCA section 408 in 1996. Although the statute had been silent 
on this issue previously, the FQPA added language specifying that when 
a hearing is requested, EPA ``shall...'' hold a public evidentiary 
hearing if and to the extent the Administrator determines that such a 
public hearing is necessary to receive factual evidence relevant to 
material issues of fact raised by the objections.'' (21 U.S.C. 
346a(g)(2)(B)). This language explicitly grants EPA broad discretion to 
deny a hearing. Specifically, the language in section 408 provides that 
EPA is to determine whether a hearing is ``necessary to receive factual 
evidence'' as well as whether the issues raised in objections are 
``material'' issues of fact. Thus, even where evidence relevant to an 
issue of material fact is proffered (essentially the standard set forth 
in 40 CFR 178.32), EPA construes the statutory language as requiring it 
to hold a hearing only where EPA determines a hearing is necessary to 
receive proffered evidence. In other words, the statute grants EPA the 
discretion to determine that the issues could be resolved entirely on 
the basis of the existing written record. See 74 FR at 59627.

C. Evidentiary Proffer by NRDC

    As noted above, the purpose for holding hearings is ``to receive 
factual evidence.'' (21 U.S.C. 346a(g)(2)(B); 53 FR 41126, 41129, 
October 19, 1988 (``Hearings are for the purpose of gathering evidence 
on disputed factual issues . . . .'')). A requestor must identify 
evidence relied upon to justify a hearing and either submit copies of 
that evidence or summarize it. (40 CFR 178.27). After reviewing the 
proffer, EPA must find that there is a reasonable possibility that the 
proffered evidence, if established, would resolve one or more 
genuinely-disputed, material factual issues in a requestor's favor. (40 
CFR 178.32(b)). Because a substantial portion of NRDC's evidentiary 
proffer is deficient on its face, EPA finds it most efficient to 
preliminarily review the proffer before turning to the individual 
issues raised by NRDC.
    NRDC identifies the following as ``relevant documentation'': Order 
denying NRDC's petition to revoke tolerances (October 29, 2008); 
Amended Carbaryl Registration Eligibility Decision (RED) (August 2008); 
Carbaryl RED (September 2007); and Carbaryl Interim RED (2003 IRED) 
(June 2003). NRDC also includes a reference to information on EPA's 
reregistration of carbaryl, available online at http:/www.epa.gov/
pesticides/reregistration/carbaryl/. EPA assumes that these are the 
documents NRDC intends to proffer as evidence in support of its request 
for a hearing.
    In addition, throughout it objections and request for a hearing, 
NRDC includes footnotes with citations to additional documents. As a 
general matter, EPA assumes NRDC is doing so in the context of it 
supporting its objections, rather than as a proffer of evidence to 
justify a hearing. Indeed, merely citing to a document in a footnote 
does not constitute a proffer of evidence. Nevertheless, in an effort 
to address NRDC's hearing request as comprehensibly as possible, EPA 
will address these footnote citations as well. In the future, however, 
NRDC would be well advised to make clear exactly what evidence it is 
proffering as a justification for its hearing request.
    The documents cited in footnotes generally fall into three 
categories. The first are EPA documents that can be grouped in the same 
category as the documents NRDC identified as ``relevant documents.'' 
These documents are: EPA Fact Sheet for Carbaryl (revised on 10/22/04); 
EPA's Organophospate Cumulative Risk Assessment (USEPA 2006); EPA's 
Revised N-Methyl Carbamate Cumulative Risk Assessment [DRAFT] (USEPA 
2007).
    This group of EPA documents, combined with the other EPA documents 
identified by NRDC as ``relevant documents'' (including ``[i]nformation 
on EPA's reregistration of carbaryl [] available online at http://
www.epa.gov/pesticides/reregistration/carbaryl/'') do not present 
evidence of a genuinely-disputed, material issue of fact. (73 FR 42694-
95, July 23, 2008) (citing to EPA decision-making record is vague and 
fails to identify new evidence which, if established, would resolve an 
issue in petitioner's favor)). First, given that the purpose of a 
hearing is to gather or receive evidence, proffering evidence already 
considered and relied upon by EPA is not sufficient justification for 
holding a hearing. Second, as a matter of law, EPA does not understand 
how it can be argued that a proffer consisting of a general reference 
to the decision-making record--which EPA has found supports one result, 
could constitute evidence that if established would justify the 
opposite conclusion. Third, EPA concludes that the non-specific 
citation to numerous documents related to the multi-year process of 
conducting FIFRA reregistration and FFDCA tolerance reassessment is so 
vague a proffer as to not constitute a proffer at all. (Id.)
    It should be noted, however, that in two cases, NRDC does offer a 
specific citation in the 2008 Amended Carbaryl RED. First, NRDC cites 
to a specific page as a reference for the largest uses of carbaryl 
(based upon pounds of active ingredient used per year): apples, 
asparagus, cherries, corn, grapefruit, grapes, hay, oranges, peaches, 
pecans, soybeans, and turf. While use information is relevant to EPA's 
overall reregistration decision, it is not material to NRDC's 
objections or its request for a hearing. As such it does not identify 
evidence that would justify holding a hearing.
    Similarly, NRDC cites to a specific page in the 2008 Amended 
Carbaryl RED for the proposition that EPA issued a data call-in for 
data on exposure from the use of carbaryl in pet collars but that those 
results had not been submitted. NRDC objects to EPA's assessment of 
carbaryl tolerances in part because EPA did not have these data. 
However, EPA has since received the data. Moreover, while this issue 
may be relevant to NRDC's objection, arguing that EPA did not have 
sufficient data upon which to make a decision (without offering into 
evidence data EPA should have but did not consider) is not a basis upon 
which to grant a hearing. Again, a hearing is for

[[Page 56009]]

the purpose of gathering or receiving evidence and to resolve material 
factual disputes. It is undisputed that at the time, EPA had not 
received the data. It is also undisputed that the data has since been 
submitted. Thus, there is no issue in dispute over the submission of 
the data or evidence to suggest otherwise. In sum, EPA does not 
consider NRDC's citations to EPA's decision-making record a sufficient 
proffer of evidence to justify a hearing.
    The second category of documents cited in footnotes consists of the 
following documents, loosely described as articles and reports: 
``Poisons on Pets. Health Hazards from Flea and Tick Products'' NRDC 
November, 2000; NRDC's 2008 Green Paws report available at http://
www.greenpaws.org/better.php; Opportunities to Improve Data Quality and 
Children's Health through the Food Quality Protection Act (FQPA) (EPA 
Inspector General Report No. 2006-P-00009 (January 10, 2006)); 2007/
2008 American Pet Products Manufacturing Association (APPA) National 
Pet Owners Survey; and Kansas State University Press Release. ``K-State 
Expert Says Fleas Can Be An Itchy Situation'' (November 16, 1999). None 
of these documents proffer evidence of a genuinely-disputed, material 
issue of fact. EPA will address each in turn.
    The NRDC publication ``Poison on Pets'' focuses on seven 
organophosphate insecticides used in flea and tick control products; 
namely, chlorpyrifos, dichlorvos, phosmet, naled, tetrachlorvinpos, 
diazinon, and malathion. As a preliminary matter, EPA need not 
determine whether the information in this publication raises a material 
issue of fact about which a meaningful hearing might be held because, 
as explained in Unit VIII.D.2, the cancellation of all carbaryl pet 
collar product registrations renders NRDC's hearing request moot. In 
addition, factually, the document's relevance to carbaryl is at most 
tangential. While the report does mention carbaryl, it does so 
primarily in the context of arguing against the use of carbamates. 
Specifically, on page 49 of 67, the report notes that carbaryl and 
propoxur are the two major carbamates used for flea control, combining 
for approximately 8% of all active ingredients used to treat pets and 
kennels. The report states that NRDC scientists believes that carbaryl 
is one of the most significant pesticide disrupters of the endocrine 
system, interfering with sperm structure and function as well as 
increasing the risk of miscarriage. The report concludes its paragraph 
on carbamates by noting that ``[f]ortunately, use of pet products with 
carbaryl already has decreased.'' (Poisons on Pets at 50). In its 
objections, NRDC relies on the report to reiterate generally applicable 
arguments that NRDC made regarding organophosphate pesticides to argue 
why NRDC also believes EPA's exposure assessment of carbaryl is flawed. 
This document, however, adds no justification for a hearing not 
otherwise included in NRDC's objections. In short, the report does not 
proffer evidence of a genuinely-disputed, material issue of fact 
related specifically to carbaryl.
    As best EPA can determine, NRDC's Green Paws report is a website 
page devoted to alternative, non-toxic methods of flea and tick 
control, such as using a flea comb and regular bathing. Again, EPA need 
not determine whether the information in this ``report'' raises a 
material issue of fact about which a meaningful hearing might be held 
because, as explained in Unit VIII.D.2, the cancellation of all 
carbaryl pet collar product registrations renders NRDC's hearing 
request moot. In addition, this ``report'' does not contain carbaryl-
specific information and does not provide any evidence of a genuinely-
disputed, material issue of fact related to NRDC's objections or 
request for a hearing. As such, it does not provide factual evidence 
justifying a hearing.
    Similarly, NRDC generally relies on the EPA Inspector General 
Report to emphasize the importance of DNT test data. This report, 
however, does not contain carbaryl-specific information and does not 
provide any evidence of a genuinely-disputed, material issue of fact 
related to NRDC's objections or request for a hearing. At best, the 
report implies that registration decisions should not be made in the 
absence of a DNT study. However, EPA's assessment of carbaryl included 
the submission and review of a DNT study. In sum, the report does not 
identify factual evidence that would, if established, resolve an issue 
in NRDC's favor.
    NRDC also cites to the 2007/2008 American Pet Product Association 
(APPA) National Pet Owners Survey for the proposition that ``nearly two 
out of every three households owns a pet, which equates to 88.3 million 
cats and 74.8 million dogs.'' First, although NRDC asserts the survey 
is available at the APPA website on-line, as far as EPA is able to 
determine this is proprietary information. For non-members, the 2009/
2010 survey (at the time of this writing) was available at a cost of 
$1,695. EPA did not purchase a copy for purposes of responding to 
NRDC's hearing request and, therefore, was unable to independently 
verify the survey results. Second, EPA need not determine whether the 
information in this survey raises a material issue of fact about which 
a meaningful hearing might be held because, as explained in Unit 
VIII.D.2, the cancellation of all carbaryl pet collar product 
registrations renders NRDC's hearing request moot. Third, a statement--
even a factual one, as to the number of households that own a pet does 
not present evidence of a genuinely-disputed, material issue of fact 
related to NRDC's objections or request for a hearing. At best, this 
information implies that because there are so many pet owners, the 
probability that some owners use carbaryl pet collars and would be 
exposed is not insignificant. However, EPA's assessment of carbaryl pet 
collars assumes exposure, including exposure to children. Accordingly, 
even if the evidence here were established, it would not resolve the 
issue identified by NRDC in its favor; namely, that EPA underestimated 
the exposure of children that come into contact with pets wearing 
carbaryl pet collars. In sum, a survey on the number of households that 
have pets does not present evidence to justify a hearing regarding the 
assumptions EPA made regarding children's exposure to pets wearing 
carbaryl pet collars.
    Finally, NRDC cites to a 1999 press release for the proposition 
that ``[e]very year Americans spend over one billion dollars on 
products designed to kill fleas and ticks on our pets.'' First, EPA was 
unable to access a copy of the press release through the web link 
provided by NRDC. Thus, it is unclear that this document could even be 
introduced as evidence. Second, EPA need not determine whether the 
information in this press release raises a material issue of fact about 
which a meaningful hearing might be held because, as explained in Unit 
VIII.D.2, the cancellation of all carbaryl pet collar product 
registrations renders NRDC's hearing request moot. Third, a statement 
as to the sales of flea and tick control products generally does not 
present any factual evidence specific to carbaryl or information 
related to NRDC's objections or request for a hearing. Fourth, the 
reference is more than a decade old. Thus, even if it were relevant to 
a current genuinely-disputed, material issue of fact, this information 
is simply out-of-date. In sum, there can be no serious contention that 
the proffer of an outdated press release that generally refers to the 
amount Americans spend on pesticides to control fleas and ticks 
presents evidence to justify a hearing.
    The third category consists of one document: Xue J, Zartarian V, 
Moya J,

[[Page 56010]]

Freeman N, Beamer P, Black K, Tulve N, Shalat S: A meta-analysis of 
children's hand-to-mouth frequency data for estimating nondietary 
ingestion exposure (Risk Anal. 2007 Apr.; 27(2): 411-20). The Xue, et 
al. 2007 paper collected hand-to-mouth frequency data from 9 available 
studies representing 429 subjects and more than 2,000 hours of behavior 
observation. A meta-analysis was conducted on these data to study 
differences in hand-to-mouth frequency based on study, age group, 
gender, and location (indoor vs. outdoor), to fit variability and 
uncertainty distributions that can be used in probabilistic exposure 
assessments, and to identify any data gaps. Results of this analysis 
indicate that age and location are important for hand-to-mouth 
frequency, but study and gender are not. This paper represents the 
first comprehensive effort to fit hand-to-mouth frequency variability 
and uncertainty distributions by indoor/outdoor location and by age 
groups, using the new standard set of age groups recommended by the 
U.S. Environmental Protection Agency for assessing childhood exposures.
    This document is ``proffered'' in connection with NRDC's objections 
and request for a hearing on issues related to EPA exposure assessment 
of carbaryl pet collar products. EPA need not determine whether the 
information in this meta-analysis raises a material issue of fact about 
which a meaningful hearing might be held because, as explained in Unit 
VIII.D.2, the cancellation of all carbaryl pet collar product 
registrations renders NRDC's hearing request moot. Nonetheless, EPA 
notes that NRDC's proffer is improper. NRDC's original Petition did not 
address this information because it pre-dated the Xue paper. However, 
NRDC's subsequent petition, dated November 26, 2007, regarding pet 
collars, which in essence amended its previous petition, also did not 
reference or rely in any manner on this information. To the contrary, 
in its pet collar petition, NRDC generally takes issue with 
modifications EPA made to the assumptions underlying the carbaryl pet 
collar residential exposure component of the probabilistic risk 
assessment of the N-methyl carbamate cumulative assessment (as compared 
to the carbaryl, single chemical, determinative assessment). In so 
doing, NRDC generally asserted that the net result of these changes is 
that EPA underestimated the exposure of children to carbaryl from pet 
collars. It is only in its request for a hearing and objections that 
NRDC raises for the first time a host of specific issues based upon the 
analysis in the Xue paper related to the carbaryl pet collar 
residential exposure component of the N-methyl carbamate cumulative 
assessment. Thus, even if the issues concerning pet collars were not 
moot, it would be inappropriate to allow NRDC to now cure a poorly 
drafted petition by recasting its arguments or raising issues for the 
first time--and proffering evidence that was previously available in 
support of such arguments had they been raised earlier--at the hearing 
and objections stage of the process. See Nat'l Corn Growers Assc. v. 
EPA, No. 09-1284, slip op. at 8-9 (C.A.D.C. July 23, 2010) (upholding 
EPA's refusal to consider at the objections stage evidence and 
arguments that could have been but were not submitted during the 
comment period); see also 72 FR at 39324 (tolerance revocation 
procedures are not ``game,'' whereby a party may file objections to 
denial based on entirely new ground(s) not relied upon in denying the 
petition.); 73 FR at 42710 (inappropriate to cure failure to offer 
evidence at an earlier stage of administrative proceeding by submitting 
such evidence with a hearing request).
    In sum, NRDC has failed to identify factual evidence sufficient to 
justify a hearing. Specifically, NRDC has failed to proffer evidence 
that, if established, would resolve one or more genuinely-disputed, 
material factual issues in its favor. Accordingly, in addition to the 
reasons discussed below, NRDC's hearing request is denied.

D. Response to Specific Issues Raised in Objections and Hearing 
Requests

    1. Failure to apply a 10X children's safety factor and another 3X 
additional safety factor to the DNT study LOAEL in calculating a safe 
dose for carbaryl or to otherwise rely on the DNT study in assessing 
the risk of carbaryl. In its objection to EPA's calculation of a safe 
dose for carbaryl, NRDC makes three, separate but related arguments: 
(1) it was unlawful for EPA to calculate the safe dose for carbaryl 
without applying a 10X children's safety factor (in addition to the 
inter- and intra-species safety factors) to the LOAEL from the DNT 
study; (2) it was unlawful for EPA to calculate the safe dose for 
carbaryl without applying an additional 3X safety factor (in addition 
to the inter- and intra-species and children's safety factors) to the 
LOAEL from the DNT study to account for the lack of a NOAEL in this 
study; and (3) ``[e]ven if the DNT data were not used to derive a [safe 
dose], EPA's failure to incorporate the important information on age-
sensitivity that is provided by the DNT is arbitrary and capricious, 
and contrary to law.'' (Ref. 1 at 8).
    NRDC's arguments concerning the application of additional safety 
factors of 10X and 3X to the DNT study LOAEL is material to its request 
for the revocation of the carbaryl tolerances only if both arguments 
are accepted - i.e., it is determined that both additional safety 
factors should be used in assessing the safety of carbaryl. This is 
because there is already essentially a tenfold difference between the 
DNT study LOAEL (10 mg/kg/day) and the POD used in calculating the safe 
dose for carbaryl. That POD is the BMDL10 of 1.1 mg/kg/day 
for brain cholinesterase inhibition in PND11 juveniles in the CCA 
study. Use of either the 10X safety factor or the 3X factor alone 
applied to the DNT study LOAEL would not produce a value lower than the 
existing POD, only a combined 30X would do that. For this reason, for 
NRDC to sustain on materiality grounds its objection and hearing 
request as to its first two arguments it must either show (1) it is 
entitled to a hearing on both arguments; (2) it is entitled to a 
hearing on one argument and, as to the other, even if it is not 
entitled to a hearing, its substantive argument is meritorious, or (3) 
if it is not entitled to a hearing on either argument, that both of its 
substantive arguments are meritorious. As explained below, NRDC has not 
made such a showing.
    a. Application of a 10X children's safety factor and a 3X safety 
factor for lack of a NOAEL to the DNT study. NRDC states that it 
``provides a scientific and legal argument that EPA must apply a 30X 
adjustment factor, based on a 10X FQPA factor to account for evidence 
for permanent structural brain damage in juvenile animals in the DNT 
study ..., and a 3X factor for the failure of the DNT study to identify 
with confidence an observable no-effect level for juvenile animals 
exposed to carbaryl.'' (Obj. at 7). Its legal argument appears to be 
that the children's safety factor provision in FFDCA section 
408(b)(2)(C) compels EPA to apply a 10X safety factor when a study 
reveals juveniles are more sensitive than adults. EPA bases this 
conclusion on three considerations: (1) the children's safety factor is 
a statutory requirement; (2) NRDC has phrased its argument regarding 
juvenile sensitivity and the 10X children's safety factor in mandatory 
terms (Ref. 2 at 4 (``Based on the reports available in the EPA 
documents demonstrating increased susceptibility in fetuses and newborn 
animals, the EPA is obligated to retain the FQPA 10X factor, in 
accordance with the law.'')); and (3) there are not specific legal 
requirements in FFDCA

[[Page 56011]]

section 408 regarding a safety factor to address the lack of a NOAEL in 
a toxicity study.
    Hearings are not granted on legal questions. (40 CFR 178.32(b)(1)). 
EPA has repeatedly concluded, and NRDC appears to have admitted, that 
its argument regarding retention of the children's safety factor to 
address juvenile sensitivity is a question of law. (73 FR 5439, 5445, 
January 30, 2008; 72 FR 52108, 52115-52117, September 12, 2007; 71 FR 
43906, 43919, August 2, 2006). Accordingly, NRDC's hearing request on 
this issue is denied.
    Turning to the merits of the objection--at least insofar as EPA is 
able to discern the basis for the objection, NRDC's objection, as well 
as its corresponding hearing request, is initially denied for a lack of 
particularity in the objection. EPA should not have to guess at the 
substance or basis for an objection. NRDC's objection is also being 
denied on the following separate grounds. EPA finds no basis for NRDC's 
interpretation of FFDCA section 408(b)(2)(C). EPA has on a number of 
occasions rejected the interpretation that the children's safety factor 
provision mandates that the absence of a particular study or a finding 
of pre- or post-natal toxicity or increased sensitivity in the young 
removes EPA's discretion to choose a different safety factor. (73 FR 
5439, 5444, January 30, 2008; 72 FR 52108, 52115-52117, September 12, 
2007; 71 FR 43906, 43919, August 2, 2006). EPA explained its rationale 
recently in responding to NRDC objections that made the same argument 
as in this case:
     The statute does direct EPA to consider ``susceptibility of 
infants and children'' to pesticides. (21 U.S.C. 346a(b)(2)(C)(i)(II)). 
It also states that an additional safety factor to protect infants and 
children shall be applied ``to take into account potential pre- and 
post-natal toxicity . . . .'' (21 U.S.C. 346a(b)(2)(C)). Nonetheless, 
in clear and unmistakable language, Congress decreed that, 
``[n]otwithstanding such requirement for an additional margin of 
safety'' to take into account potential pre- and post-natal toxicity, 
EPA is authorized to choose a different safety factor if EPA has 
reliable data showing a different factor is safe. (Id.). Interpreting 
the statute as creating a rigid, per se rule that the identification of 
sensitivity in the young removes EPA's discretion to choose a different 
safety factor is inconsistent with this language and the flexibility 
granted to the Agency.
(72 FR at 52117; see also 73 FR at 5444). NRDC has raised no arguments 
in its current objections that convince EPA to vary from its long-held 
interpretation. Accordingly, EPA denies NRDC's objection with respect 
to retaining a 10X children's safety factor.
    Even giving NRDC every benefit of the doubt, and assuming it did 
not intend its argument on the 10X children's safety factor to be only 
a legal question, NRDC is still not entitled to a hearing or relief on 
the merits. Perhaps NRDC was suggesting that (1) its assertion that the 
brain effects in the DNT were ``severe and permanent'' and (2) its 
claim that the DNT is a particularly important study due to its focus 
on cognitive effects, were sufficient factual reasons, when combined 
with the sensitivity finding, to compel EPA to retain the 10X 
children's safety factor even if EPA was not legally required to do so 
solely based on a finding of sensitivity in the young.
    There are several reasons no hearing is required on this re-
articulation of NRDC's claim. First, NRDC has proffered no evidence in 
support of its assertion on sensitivity and nature of the effects in 
the young. EPA reached quite different conclusions on the significance 
of the effects seen in the pups at the LOAEL in the DNT study. 
Nonetheless, NRDC has merely recycled its prior comments without 
acknowledging EPA's findings or attempting to assert that there is a 
disputed question of fact regarding how EPA has characterized the 
effects in the study. Critically, NRDC proffers no evidence (or even 
arguments) in support of its assertions. As such, NRDC's claims about 
sensitivity and the nature of the effects in pups in the DNT study are 
nothing more than ``mere allegations'' and hardly qualify as a relevant 
objection. Indeed, EPA's regulations specifically state that ``[a]n 
evidentiary hearing will not be granted on the basis of mere 
allegations, denials, or general descriptions of positions and 
contentions . . . .'' (40 CFR 178.32(b)(2)).
    Second, NRDC's argument that, as between the carbaryl CCA and the 
DNT study, EPA failed to give proper consideration and weight to the 
DNT study does not present a genuine issue of material fact to be 
resolved at a hearing. Nat'l Corn Growers Assc. v. EPA, No. 09-1284, 
slip op. at 13 (C.A.D.C. July 23, 2010) (``there is no material issue 
of fact based upon `[m]ere differences in the weight or credence given 
to particular scientific studies.'''); (47 FR at 55474) (``[Objectors] 
assertion about this evidence is, at best, an argument that a different 
inference (i.e., that the pieces are not `reasonably uniform' and `cube 
shaped') should be drawn from established fact (the dimensions of the 
pieces) than the agency has drawn. No hearing is required in such 
circumstances.''); C.f. Norvich, 773 F.2d 1363 (``differences in the 
weight or credence given to particular scientific studies ... are 
insufficient [to show a material issue of fact for a hearing]''). Here, 
all NRDC has done is point to a study already in the record that EPA 
has reviewed and considered numerous times. Thus, NRDC has failed to 
proffer any evidence to suggest that there is a factual, rather than an 
interpretive, matter to be resolved at a hearing. See Nat'l Corn 
Growers Assc. v. EPA, No. 09-1284, slip op. at 13 (a ``dispute between 
experts'' as to the weight or credence given a particular scientific 
study does not present a material issue of fact for a hearing).
    Third, NRDC's claims regarding the unique endpoints examined in the 
DNT study and its importance in evaluating the safety of pesticides are 
not disputed facts. EPA does not contest these points. A hearing will 
only be granted if there is a ``genuine and substantial issue of fact 
for resolution at a hearing.'' (40 CFR 178.32(b)(1)).
    Finally, a hearing is also denied on this re-articulated claim 
because at bottom it calls for a policy determination. NRDC is claiming 
that based on certain facts an additional safety factor is needed. This 
is a policy judgment for EPA not a factual determination on which 
evidence could be submitted for adjudication. ``An evidentiary hearing 
will not be granted on issues of policy or law.'' (Id.)
    On the merits, this re-articulated claim fails as well. First, it 
is denied because it has not been made with the particularity required. 
The statute requires that objections ``specif[y] with particularity the 
provisions of the regulation or order deemed objectionable and stating 
reasonable grounds therefore,'' and EPA's regulations make clear that 
for an objection to be properly presented it must explain ``with 
particularity . . . [its] basis . . . .'' (40 CFR 178.25(a)(2)); see 
Nat'l Corn Growers Assc. v. EPA, No. 09-1284, slip op. at 11. Second, 
EPA's conclusions on sensitivity and the nature of the effects on the 
pups in the DNT study differ significantly from NRDC's assertions and 
are well supported in the record. On the nature of the effects, EPA 
concluded that the changes in brain morphometrics for pups seen in the 
DNT were minimal. (See Unit IV.B.4.b). In addition, the data from the 
DNT study showed that for the

[[Page 56012]]

first generation pups, there were no treatment-related effects on pup 
weight, pup survival indices, developmental landmarks, FOB 
measurements, or motor activity assessments. These conclusions are 
found on a careful analysis of the DNT study. On the other hand, NRDC 
merely restates its previous comments and neither offers an explanation 
for its characterization of the DNT study results nor proffers any 
evidence in support of its allegation. (Id.) (``by simply resubmitting 
their Comments, without addressing the responses the EPA had made to 
them ... [petitioners] `failed to lodge a relevant objection'''). On 
the sensitivity of the young, EPA concluded that the brain morphometric 
effects in the juvenile rats in the DNT study would not be present at 1 
mg/kg/day. Thus, EPA has determined that the LOAELs and NOAELs for 
adults and juveniles in the DNT study were the same. NRDC has offered 
no reasons as to why EPA's findings on these points was in error. (Id.) 
Indeed, there is nothing to suggest that EPA's conclusion that these 
findings on sensitivity and the nature of the effects in the young did 
not require retention of a 10X factor was unreasonable. To the 
contrary, this conclusion is consistent with both EPA policy and 
practice. While on occasion EPA has applied an additional children's 
safety factor based solely on the nature of the effects seen in the 
young, such additional safety factors have only been utilized in 
situations involving significantly different factual circumstances. 
(See 74 FR 39545, 39549-39550, August 7, 2009) (for pesticide that 
showed sensitivity in the young, 3X children's safety factor retained 
due to very narrow dose range (3X) from NOAEL to fatal dose level). 
Third, as to the NRDC's assertions regarding the importance of the DNT 
study, EPA would note that there is a DNT study for carbaryl and it has 
been fully considered in assessing the risk of carbaryl. Importantly, 
in evaluating that study, EPA determined based on the effects seen in 
that study at what level a NOAEL for pup effects was likely to have 
been seen and that level is nearly identical to the level used as the 
POD for assessing carbaryl risks. For all of these reasons, this 
objection is denied.
    Having denied NRDC's objection that a 10X children's safety factor 
is required due to the alleged identification of age sensitivity, 
NRDC's claim regarding a 3X factor due to the lack of a NOAEL in the 
DNT study becomes immaterial. As noted above, additional factors of 10X 
or below applied to the DNT study LOAEL for pups (along with the 
standard inter- and intra-species safety factors) will not result in a 
lower aPAD for carbaryl and thus granting NRDC's objection would not 
change EPA's safety determination. Because NRDC's objection on this 
issue is not outcome-determinative, it is denied on the basis of 
immateriality. See Nat'l Corn Growers Assc. v. EPA, No. 09-1284, slip 
op. at 13; 72 FR 39318, 39323-39324, July 18, 2007. In addition, there 
are no disputed facts with regard to the question of whether an 
additional safety factor is needed to address the lack of a NOAEL in 
the DNT study. NRDC asserts that an additional 3X safety factor should 
be applied to the DNT study LOAEL for pups because no NOAEL was 
identified for that test group. EPA agrees that if it were using the 
pup LOAEL from the DNT study as a POD, at least a 3X factor is needed 
to account for the lack of a NOAEL in that study. In fact, in its risk 
assessment, EPA essentially applied a safety factor of 10X to the DNT 
study's LOAEL (10 mg/kg/day) by its determination that no brain 
morphometric effects would be expected at the mid-dose (1 mg/kg/day). 
Thus, EPA does not disagree with NRDC's assertion that an additional 
safety factor is needed to address the lack of a NOAEL in the DNT 
study. In sum, because this objection is immaterial and there are no 
disputed material facts, NRDC's hearing request and objection on this 
issue are denied. (40 CFR 178.32(b)).
    b. Arbitrary and capricious. NRDC argues that even if EPA uses the 
BMDL10 for PND11 juveniles from the CCA study for the POD 
for calculating the carbaryl safe dose, it must ``incorporate the 
important information on age-sensitivity that is provided by the DNT 
[study]'' into its risk assessment and that EPA's failure to do so was 
arbitrary and capricious. (Ref. 1 at 8). The only hint that NRDC 
provides as to what it means by this vague allegation is a table 
appearing on page eight of its objections in which NRDC suggests that 
the additional 10X and 3X safety factors it argues are needed for the 
DNT study should be applied to the BMDL10 for PND11 
juveniles in the CCA study in computing the safe dose. NRDC advances no 
specific argument as to why this approach should be taken and proffers 
no evidence in support of it. As an initial matter, therefore, this 
objection and its corresponding hearing request is denied for a lack of 
particularity in the objection. EPA should not have to guess at the 
substance of an objection.
    Even assuming the objection passes the particularity requirement, 
it is without merit. The predicate to this argument is that additional 
safety factors are needed as to the pup LOAEL in the DNT study. Thus, 
this objection and hearing request stand in the shoes of the objections 
and hearing requests regarding the alleged need for additional 10X and 
3X safety factors on the pup LOAEL in the DNT study. As to the 
additional 10X children's safety factor, NRDC's objection and hearing 
request is denied for the identical reasons that EPA denied NRDC's 
direct claims regarding an additional 10X children's safety factor. As 
to the 3X safety factor, NRDC's assertion that a lack of a NOAEL in the 
DNT study necessitates the application of an additional safety factor 
to the POD in the CCA study does not warrant a hearing and is 
substantively meritless because it is nothing more than a mere 
allegation without any supporting basis. (40 CFR 178.32(b)(2)). NRDC 
offers no evidence as to why a LOAEL-to-NOAEL safety factor should be 
transferred from a study where it is needed (the DNT study) to a study 
where a clear NOAEL or its equivalent (a BMDL10) is 
identified (the CCA study). Further, to the extent that NRDC intended 
to make some other point by its vague claim that it was arbitrary and 
capricious for EPA not to take the DNT study results into account in 
its carbaryl safety determination, its hearing request is denied as 
being no more than a ``general description of [a] position[],'' 40 CFR 
178.32(b)(2), and the objection is denied on the ground that the 
record, on its face, shows that EPA carefully considered the results of 
the DNT study in making its safety determination on carbaryl. (See Unit 
IV.B.4.b).
    2. Improper reliance on flawed data for exposure assessment 
resulting in underestimation of exposure to children from pet collars. 
NRDC makes several arguments as to why EPA's exposure assessment is 
flawed and, therefore, EPA cannot make its tolerance safety finding for 
carbaryl. NRDC first argues that EPA cannot make its safety finding 
because required transferable residue studies have not yet been 
submitted. NRDC further argues that the exposure studies that EPA did 
rely on are highly variable and unreliable and, therefore, EPA cannot 
be reasonably certain that children in the highly exposed tails of the 
exposure curve will be protected. NRDC also argues that EPA made 
several unfounded or faulty assumptions in it exposure assessment such 
that EPA cannot show that there is an unreasonable certainty of no harm 
from the aggregate exposures to carbaryl.
    EPA denies both the hearing request and the objections as moot 
because all carbaryl pet collar registrations have

[[Page 56013]]

been cancelled. In a letter dated September 30, 2009, Wellmark 
International submitted a request to voluntarily cancel its pet collar 
registrations pursuant to section 6(f) of FIFRA. (74 FR 54045, October 
21, 2009). These are the only carbaryl pet collar registrations and the 
last remaining pet product registration for carbaryl. EPA issued its 
final order cancelling carbaryl registrations for pet collar uses on 
December 16, 2009. (74 FR 66642).

E. Conclusion on Objections and Request for a Hearing

    For the reasons stated above, all of the NRDC's objections as well 
as its request for a hearing are denied.

IX. Regulatory Assessment Requirements

    As indicated previously, this action announces the Agency's final 
order regarding objections filed under section 408 of FFDCA. 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.

X. Submission to Congress and the Comptroller General

    The Congressional Review Act, (5 U.S.C. 801 et seq.), as added by 
the Small Business Regulatory Enforcement Fairness Act of 1996, does 
not apply because this action is not a rule for purposes of 5 U.S.C. 
804(3).

XI. References

    1. Natural Resources Defense Council, ``Objections to the Order 
Denying NRDC's Petition to Revoke All Tolerances for Carbaryl, and 
Request for Public Evidentiary Hearing'' (December 29, 2008).
    2. Natural Resources Defense Council, Petition to Revoke All 
Carbaryl Tolerances and Cancel All Carbaryl Registrations, (January 
10, 2005).
    3. Natural Resources Defense Council, Petition to Cancel 
Carbaryl and Propoxur for Pet Collar Uses, (November 26, 2007).
    4. US EPA, Carbaryl; Order Denying NRDC's Petition to Revoke 
Tolerances, 73 FR 64229, October 29, 2008.
    5. US EPA, ``A User's Guide to Available EPA Information on 
Assessing Exposure to Pesticides in Food'' (June 21, 2000).
    6. FIFRA Science Advisory Panel. 2002. Methods Used to Conduct a 
Preliminary Cumulative Risk Assessment for Organophosphate 
Pesticides. Final Report from the FIFRA Scientific Advisory Panel 
Meeting of February 5-7, 2002 (Report dated March 19, 2002). FIFRA 
Scientific Advisory Panel, Office of Science Coordination and 
Policy, Office of Prevention, Pesticides and Toxic Substances, U.S. 
Environmental Protection Agency. Washington, DC. SAP Report 2002-01.
    7. FIFRA Science Advisory Panel. 2005a. Final report on N-Methyl 
Carbamate Cumulative Risk Assessment: Pilot Cumulative Analysis. 
Final Report from the FIFRA Scientific Advisory Panel Meeting of 
February 2005 (Report dated September 2, 1998). Available at: http:/
/www.epa.gov/scipoly/sap/2005/february/minutes.pdf.
    8. FIFRA Science Advisory Panel. 2005b. Final report on 
Preliminary N-Methyl Carbamate Cumulative Risk Assessment. Final 
Report from the FIFRA Scientific Advisory Panel Meeting of July 29-
30, 2005 (Report dated September -, 2005). Available at: http://
www.epa.gov/scipoly/sap/2005/august/minutes.pdf.
    9. Office of Pesticide Programs, US EPA, ``Office of Pesticide 
Programs' Policy on the Determination of the Appropriate FQPA Safety 
Factor(s) For Use in the Tolerance Setting Process'' (February 28, 
2002).
    10. US EPA Office of Pesticide Programs, ``The Use of Data on 
Cholinesterase Inhibition for Risk Assessments of Organophosphorous 
and Carbamate Pesticides'' (August 18, 2000).
    11. US EPA Office of Pesticide Programs. March 9, 2005 letter to 
Peg Cherney, Bayer Crop Science, Final Cancellation Order for 
Carbaryl Liquid Broadcast Application to Lawns/Turf; EPA 
Registration Numbers 264-324, 264-325, and 264-328.
    12. US EPA Office of Pesticide Programs. 2007. Office of 
Prevention, Pesticides and Toxic Substances, EPA, Reregistration 
Eligibility Decision for Carbaryl (September 24, 2007).
    13. US EPA Office of Pesticide Programs. 2002. Hazard 
Identification Assessment Review Committee (HIARC) report (March 5, 
2002).
    14. US EPA Office of Pesticide Programs. 2002. FQPA SF Committee 
report (April 3, 2002).
    15. US EPA Office of Pesticide Programs. 2002. HIARC report (May 
9, 2002).
    16. Moser, G. (2007) Report of Cholinesterase Comparative 
Sensitivity Study of Carbaryl. Unpublished study prepared by US EPA, 
ORD, NHEERL. (MRID 47143001).
    17. US EPA Office of Pesticide Programs. 2007. Carbaryl: Updated 
Endpoint Selection for Single Chemical Risk Assessment (June 29, 
2007).
    18. US EPA Office of Pesticide Programs. 2007b. Carbaryl. HED 
Chapter of the Reregistration Eligibility Decision Document (RED). 
EPA-HQ-OPP-2007-0941-0003. PC Code: 056801, DP Barcode: D334770. 
(June 28, 2007).
    19. Johnson, C.D. and Russell, R.L. (1975) A rapid, simple 
radiometric assay for cholinesterase, suitable for multiple 
determinations. Analytical Biochemistry. 64:229-238.
    20. US EPA Office of Pesticide Programs. 1998. Hazard 
Identification Assessment Review Committee (HIARC) report (July 7, 
1998).
    21. US EPA Office of Pesticide Programs. 1998. FQPA SF Committee 
report (August 27, 1998).
    22. US EPA Office of Pesticide Programs. 1999. HIARC report 
(April 27, 1999).
    23. US EPA Office of Pesticide Programs. 1999. HIARC report 
(November 15, 1999).
    24. US EPA Office of Pesticide Programs. 1999. FQPA SF Committee 
report (December 13, 1999).
    25. US EPA Office of Pesticide Programs. 2001. HIARC report 
(April 5, 2001).
    26. US EPA Office of Pesticide Programs. 2001. FQPA SF Committee 
report (April 30, 2001).

List of Subjects in 40 CFR Part 180

    Environmental protection, Carbaryl, Pesticides and pests.

    Dated: September 8, 2010.
Steven Bradbury,
Director, Office of Pesticide Programs
[FR Doc. 2010-22987 Filed 9-14-10; 8:45 am]
BILLING CODE 6560-50-S