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Clomazone; Pesticide Tolerance

Note: EPA no longer updates this information, but it may be useful as a reference or resource.


 [Federal Register: February 14, 2001 (Volume 66, Number 31)]
[Rules and Regulations]               
[Page 10196-10204]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr14fe01-6]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[OPP-301101; FRL-6764-2]
RIN 2070-AB78]

 
Clomazone; Pesticide Tolerance

AGENCY:  Environmental Protection Agency (EPA).

ACTION:  Final rule.

-----------------------------------------------------------------------

SUMMARY:  This regulation establishes tolerances for residues of 
clomazone in or on tuberous and corm vegetable (except potato) subgroup 
crop and cucurbit vegetable crop group. Interregional Research Project 
Number 4 (IR--4) requested these tolerances under the Federal Food, 
Drug, and Cosmetic Act, as amended by the Food Quality Protection Act 
of 1996.

DATES:  This regulation is effective February 14, 2001. Objections and 
requests for hearings, identified by docket control number OPP-301101, 
must be received by EPA on or before April 16, 2001.

ADDRESSES:  Written objections and hearing requests may be submitted by 
mail, in person, or by courier. Please follow the detailed instructions 
for each method as provided in Unit VI. of the SUPPLEMENTARY 
INFORMATION. To ensure proper receipt by EPA, your objections and 
hearing requests must identify docket control number OPP-301101 in the 
subject line on the first page of your response.

FOR FURTHER INFORMATION CONTACT:  By mail: Shaja R. Brothers, 
Registration Division (7505C), Office of Pesticide Programs, 
Environmental Protection

[[Page 10197]]

Agency, 1200 Pennsylvania Ave., NW.,Washington, DC 20460; telephone 
number: (703) 308-3194; and e-mail address: brothers.shaja@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be affected by this action if you are an agricultural 
producer, food manufacturer, or pesticide manufacturer. Potentially 
affected categories and entities may include, but are not limited to:

------------------------------------------------------------------------
                                                          Examples of
           Categories                 NAICS codes         potentially
                                                       affected entities
------------------------------------------------------------------------
Industry                          111                 Crop production
  ..............................  112                 Animal production
                                  311                 Food manufacturing
  ..............................  32532               Pesticide
                                                       manufacturing
------------------------------------------------------------------------

    This listing is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed in the table could also be 
affected. The North American Industrial Classification System (NAICS) 
codes have been provided to assist you and others in determining 
whether or not this action might apply to certain entities. If you have 
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 Additional Information, Including Copies of this 
Document and Other Related Documents?

    1. Electronically. You may obtain electronic copies of this 
document, and certain other related documents that might be available 
electronically, from the EPA Internet Home Page at http://www.epa.gov/. 
To access this document, on the Home Page select ``Laws and 
Regulations'', ``Regulations and Proposed Rules,'' and then look up the 
entry for this document under the `` Federal Register--Environmental 
Documents.'' You can also go directly to the Federal Register listings 
at http://www.epa.gov/fedrgstr/. To access the OPPTS Harmonized 
Guidelines referenced in this document, go directly to the guidelines 
at http://www.epa.gov/opptsfrs/home/guidelin.htm.
    2. In person. The Agency has established an official record for 
this action under docket control number OPP-301101. The official record 
consists of the documents specifically referenced in this action, and 
other information related to this action, including any information 
claimed as Confidential Business Information (CBI). This official 
record includes the documents that are physically located in the 
docket, as well as the documents that are referenced in those 
documents. The public version of the official record does not include 
any information claimed as CBI. The public version of the official 
record, which includes printed, paper versions of any electronic 
comments submitted during an applicable comment period is available for 
inspection in the Public Information and Records Integrity Branch 
(PIRIB), Rm. 119, Crystal Mall #2, 1921 Jefferson Davis Hwy., 
Arlington, VA, from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays. The PIRIB telephone number is (703) 305-5805.

II. Background and Statutory Findings

    In the Federal Register of December 6, 2000 (65 FR 76249) (FRL-
6755-4), EPA issued a notice pursuant to section 408 of the Federal 
Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a as amended by the 
Food Quality Protection Act of 1996 (FQPA) (Public Law 104-170) 
announcing the filing of pesticide petitions (PP 9E6063 and 7E4865) for 
tolerance by IR-4, 681 U.S. Highway #1 South, North Brunswick, New 
Jersey 08902-3390. This notice included a summary of the petitions 
prepared by FMC Corporation, the registrant. There were no comments 
received in response to the notice of filing.
    The petition requested that 40 CFR 180.425 be amended by 
establishing tolerances for residues of the herbicide clomazone, [2-(2-
chlorophenyl)methyl-4,4-dimethyl-3-isoxazolidinone], in or on tanier, 
cassava, yams, arracacha, and cucurbit vegetables at 0.05 and 0.1 parts 
per million (ppm). The petition was subsequently amended to tuberous 
and corm vegetable (except potato) crop subgroup and cucurbit vegetable 
crop group at 0.05 ppm.
    Section 408(b)(2)(A)(i) of the FFDCA allows EPA to establish a 
tolerance (the legal limit for a pesticide chemical residue in or on a 
food) only if EPA determines that the tolerance is ``safe.'' Section 
408(b)(2)(A)(ii) defines ``safe'' 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.'' This 
includes exposure through drinking water and in residential settings, 
but does not include occupational exposure. Section 408(b)(2)(C) 
requires EPA to give special consideration to exposure of infants and 
children to the pesticide chemical residue in establishing a tolerance 
and to ``ensure that there is a reasonable certainty that no harm will 
result to infants and children from aggregate exposure to the pesticide 
chemical residue....''
    EPA performs a number of analyses to determine the risks from 
aggregate exposure to pesticide residues. For further discussion of the 
regulatory requirements of section 408 and a complete description of 
the risk assessment process, see the final rule on Bifenthrin Pesticide 
Tolerances (62 FR 62961, November 26, 1997) (FRL-5754-7).

III. Aggregate Risk Assessment and Determination of Safety

    Consistent with section 408(b)(2)(D), EPA has reviewed the 
available scientific data and other relevant information in support of 
this action. EPA has sufficient data to assess the hazards of and to 
make a determination on aggregate exposure, consistent with section 
408(b)(2), for a tolerance for residues of clomazone on the tuberous 
and corm vegetable (except potato) crop subgroup and cucurbit vegetable 
crop group at 0.05 ppm. EPA's assessment of exposures and risks 
associated with establishing the tolerance follows.

A. Toxicological Profile

    EPA has evaluated the available toxicity data and considered its 
validity, completeness, and reliability as well as the relationship of 
the results of the studies to human risk. EPA has also considered 
available information concerning the variability of the sensitivities 
of major identifiable subgroups of consumers, including infants and 
children. The nature of the toxic effects caused by clomazone are 
discussed in the following Table 1 as well as the no observed adverse 
effect level (NOAEL) and the lowest observed adverse effect level 
(LOAEL) from the toxicity studies reviewed.

[[Page 10198]]



           Table 1. -- Subchronic, Chronic, and Other Toxicity
------------------------------------------------------------------------
         Guideline No.               Study Type            Results
------------------------------------------------------------------------
870.3100                         90-Day oral         NOAEL = 135.2/160.9
                                  toxicity rat        mg/kg/day, males/
                                                      females LOAEL =
                                                      273/319.3 mg/kg/
                                                      day, males/
                                                      females, based on
                                                      decreased body
                                                      weight, body
                                                      weight gains, food
                                                      consumption and
                                                      increased absolute
                                                      and relative liver
                                                      weights in females
                                                      and increased
                                                      absolute liver
                                                      weights in males
------------------------------------------------------------------------
870.3100                         90-Day oral         NOAEL ³
                                  toxicity mouse      1,200 mg/kg/day
                                                      (limit dose) LOAEL
                                                      > 1,200 mg/kg/day
------------------------------------------------------------------------
870.3700a                        Prenatal            Maternal NOAEL =
                                  developmental rat   100 mg/kg/day
                                                      LOAEL = 300 mg/kg/
                                                      day based on
                                                      chromorhinorrhea
                                                      and/or
                                                      abdominogenital
                                                      staining
                                                      Developmental
                                                      NOAEL = 100 mg/kg/
                                                      day LOAEL = 300 mg/
                                                      kg/day based on
                                                      indications of
                                                      delayed
                                                      ossification in
                                                      the form of either
                                                      partial
                                                      ossification or
                                                      the absence of
                                                      manubrium,
                                                      sternebrae 3-4,
                                                      xiphoid, caudal,
                                                      and metacarpals
------------------------------------------------------------------------
870.3700b                        Prenatal            Maternal NOAEL =
                                  developmental       240 mg/kg/day
                                  rabbits             LOAEL = 700 mg/kg/
                                                      day based on
                                                      effects seen at
                                                      1,000 mg/kg/day,
                                                      which included
                                                      mortality,
                                                      abortions,
                                                      decreased body
                                                      weight gain, and
                                                      decreased
                                                      defecation or no
                                                      feces
                                                      Developmental
                                                      NOAEL ³
                                                      700 mg/kg/day
                                                      highest dose
                                                      tested (HDT) LOAEL
                                                      > 700 mg/kg/day
------------------------------------------------------------------------
870.3800                         2-Generation        Parental NOAEL = 50
                                  reproduction and    mg/kg/day LOAEL =
                                  fertility effects   100 mg/kg/day
                                                      based on
                                                      statistically
                                                      significantly
                                                      decreased body
                                                      weight and body
                                                      weight gain during
                                                      pre-mating, and
                                                      decreased body
                                                      weight during
                                                      gestation &
                                                      lactation male &
                                                      female. In
                                                      addition decreased
                                                      food consumption
                                                      in females and
                                                      hydro-nephritic
                                                      kidneys in males.
                                                      Offspring NOAEL =
                                                      50 mg/kg/day LOAEL
                                                      = 100 mg/kg/day
                                                      based on decreased
                                                      body weight in F2a
                                                      and F2b litters
------------------------------------------------------------------------
870.4100b                        Chronic toxicity    NOAEL ³
                                  dogs                1,038/1,012 mg/kg/
                                                      day, males/females
                                                      (HDT) LOAEL >
                                                      1,038/1,012 mg/kg/
                                                      day
------------------------------------------------------------------------
870.4300                         Chronic toxicity/   NOAEL = 84.4/112.9
                                  Carcinogenicity     mg/kg/day, males/
                                  rats                females (HDT)
                                                      LOAEL ³
                                                      84.4/112.9 mg/kg/
                                                      day, males/females
                                                      Classified as a
                                                      ``not likely human
                                                      carcinogen''
------------------------------------------------------------------------
870.4300                         Carcinogenicity     NOAEL = 300 mg/kg/
                                  mice                day (HDT) LOAEL =
                                                      > 300 mg/kg/day
                                                      Classified as a
                                                      ``not likely human
                                                      carcinogen''
------------------------------------------------------------------------
870.5100                         Gene mutation       The test article
                                  Salmonella          was assayed up to
                                  typhimurium and     cytotoxic
                                  Escherichia coli    concentrations
                                  reverse gene        (5,000 mg/
                                  mutation assay)     plate), but in no
                                                      instance were
                                                      appreciably
                                                      increased number
                                                      of revertants to
                                                      histidine
                                                      prototrophy (his+)
                                                      found in any of
                                                      the tester
                                                      strains, either in
                                                      the presence or
                                                      absence of
                                                      metabolic
                                                      activation.
------------------------------------------------------------------------
870.5395                         Cytogenetics In     Negative. The
                                  vivo rat            incidence of
                                                      aberrations and
                                                      the aberrations/
                                                      cell were not
                                                      significantly
                                                      increased.
------------------------------------------------------------------------
870.5550                         Other effects In    Clomazone was
                                  vitro UDS assay     tested up to
                                  in primary rat      cytotoxicity
                                  hepatocytes         (relative toxicity
                                                      at 0.10 mL/
                                                      mL was 88.6%), but
                                                      in no cultures
                                                      treated with test
                                                      article was a
                                                      significant
                                                      increase in mean
                                                      net nuclear counts
                                                      indicative of UDS
                                                      recorded.
------------------------------------------------------------------------
870.7485                         Metabolism and      Clomazone is
                                  pharmacokinetics    extensively
                                                      metabolized by the
                                                      liver and excreted
                                                      in the urine and
                                                      feces within 24
                                                      hours. Sixteen
                                                      metabolites,
                                                      including the
                                                      parent, were
                                                      identified; and
                                                      the predominant
                                                      route of excretion
                                                      was in urine.
------------------------------------------------------------------------

B. Toxicological Endpoints

    The dose at which no adverse effects are observed (the NOAEL) from 
the toxicology study identified as appropriate for use in risk 
assessment is used to estimate the toxicological level of concern 
(LOC). However, the lowest dose at which adverse effects of concern are 
identified (the LOAEL) is sometimes used for risk assessment if no 
NOAEL was achieved in the toxicology study selected. An uncertainty 
factor (UF) is applied to reflect uncertainties inherent in the 
extrapolation from laboratory animal data to humans and in the 
variations in sensitivity among members of the human population as well 
as other unknowns. An UF of 100 is routinely used, 10X to account for 
interspecies differences and 10X for intraspecies differences.
    For dietary risk assessment (other than cancer) the Agency uses the 
UF to calculate an acute or chronic reference dose (acute RfD or 
chronic RfD) where the RfD is equal to the NOAEL divided by the 
appropriate UF (RfD = NOAEL/UF). Where an additional safety factor is 
retained due to concerns unique to the FQPA, this additional factor is 
applied to the RfD by dividing the RfD by such additional factor. The 
acute or chronic

[[Page 10199]]

Population Adjusted Dose (aPAD or cPAD) is a modification of the RfD to 
accommodate this type of FQPA Safety Factor.
    For non-dietary risk assessments (other than cancer) the UF is used 
to determine the LOC. For example, when 100 is the appropriate UF (10X 
to account for interspecies differences and 10X for intraspecies 
differences) the LOC is 100. To estimate risk, a ratio of the NOAEL to 
exposures (margin of exposure (MOE) = NOAEL/exposure) is calculated and 
compared to the LOC.
    The linear default risk methodology (Q1*) is the primary 
method currently used by the Agency to quantify carcinogenic risk. The 
Q1* approach assumes that any amount of exposure will lead 
to some degree of cancer risk. A Q1* is calculated and used 
to estimate risk which represents a probability of occurrence of 
additional cancer cases (e.g., risk is expressed as 1 x 
10-\6\ or one in a million). Under certain specific 
circumstances, MOE calculations will be used for the carcinogenic risk 
assessment. In this non-linear approach, a `` point of departure'' is 
identified below which carcinogenic effects are not expected. The point 
of departure is typically a NOAEL based on an endpoint related to 
cancer effects though it may be a different value derived from the dose 
response curve. To estimate risk, a ratio of the point of departure to 
exposure (MOE cancer = point of departure/exposures) is calculated. A 
summary of the toxicological endpoints for clomazone used for human 
risk assessment is shown in the following Table 2:

        Table 2.--Summary of Toxicological Dose and Endpoints For Clomazone Use in Human Risk Assessment
----------------------------------------------------------------------------------------------------------------
                                                                 FQPA SF* and Level of
          Exposure Scenario               Dose Used in Risk         Concern for Risk     Study and Toxicological
                                            Assessment, UF             Assessment                Effects
----------------------------------------------------------------------------------------------------------------
Acute Dietary females 13-50 years of   NOAEL = 100 mg/kg/day    FQPA SF = 1X             Developmental rat
 age
                                       UF = 100                 aPAD = acute RfD         LOAEL = 300 mg/kg/day
                                                                 ¸FQPA SF = 1.0    based on delayed
                                                                 mg/kg/day                ossification.
                                       Acute RfD = 1.0 mg/kg/
                                        day
----------------------------------------------------------------------------------------------------------------
Acute Dietary general population       None                     None                     A risk assessment is
 including infants and children                                                           not required for this
                                                                                          population subgroup.
----------------------------------------------------------------------------------------------------------------
Chronic Dietary all populations        NOAEL= 84.4 mg/kg/day    FQPA SF = 1X             2--year rat feeding
                                                                                          study
                                       UF = 100                 cPAD = chronic RfD       LOAEL > 84.4 mg/kg/day
                                                                 ¸ FQPA SF =       (HDT)
                                                                 0.84 mg/kg/day
                                       Chronic RfD = 0.84 mg/                            90--day oral rat
                                        kg/day
                                                                                         LOAEL = 319.3 mg/kg/day
                                                                                          based on based on
                                                                                          decreased body weight,
                                                                                          body weight gains,
                                                                                          food consumption and
                                                                                          increased absolute and
                                                                                          relative liver weights
                                                                                          in females and
                                                                                          increased absolute
                                                                                          liver weights in
                                                                                          males.
                                                                                         2--Generation
                                                                                          Reproduction
                                                                                         LOAEL = 100 mg/kg/day
                                                                                          based on statistically
                                                                                          significantly
                                                                                          decreased body weight
                                                                                          & body weight gain
                                                                                          during pre-mating, and
                                                                                          decreased body weight
                                                                                          during gestation &
                                                                                          lactation male &
                                                                                          female. In addition
                                                                                          decreased food
                                                                                          consumption in females
                                                                                          and hydro-nephritic
                                                                                          kidneys in males.
----------------------------------------------------------------------------------------------------------------
Oral, Short-Term (1 to 7 days)         None                     None                     No residential uses. An
 (Residential)                                                                            endpoint was not
                                                                                          selected.
----------------------------------------------------------------------------------------------------------------
Oral, Intermediate-Term (1 week to     None                     None                     No residential uses. An
 several months) (Residential)                                                            endpoint was not
                                                                                          selected.
----------------------------------------------------------------------------------------------------------------
Dermal and Inhalation Short-Term (1    Maternal                 LOC for MOE = 100        Developmental rat study
 to 7 days) (Residential)
                                       NOAEL= 100 mg/kg/day                              Maternal
                                       Dermal absorption =                               LOAEL = 300 mg/kg/day,
                                        100%                                              based on
                                                                                          chromorhinorrhea and
                                                                                          abdominogenital
                                                                                          staining
                                       Inhalation absorption =
                                        100%
----------------------------------------------------------------------------------------------------------------
Dermal and Inhalation, Intermediate-   Oral                     LOC for MOE = 100        2-year rat feeding
 term (1 week - several months) and                                                       study
 Long-Term (several months -
 lifetime) (Residential)
                                       NOAEL= 84.4 mg/kg/day                             LOAEL > 84.4 mg/kg/day
                                                                                          (HDT)
                                                                                         90-day oral rat

[[Page 10200]]


                                                                                         LOAEL = 319.3 mg/kg/day
                                                                                          based on based on
                                                                                          decreased body weight,
                                                                                          body weight gains,
                                                                                          food consumption and
                                                                                          increased absolute and
                                                                                          relative liver weights
                                                                                          in females and
                                                                                          increased absolute
                                                                                          liver weights in males
                                                                                         2-Generation
                                                                                          Reproduction
                                                                                         LOAEL = 100 mg/kg/day
                                                                                          based on statistically
                                                                                          significantly
                                                                                          decreased body weight
                                                                                          and body weight gain
                                                                                          during pre-mating, and
                                                                                          decreased body weight
                                                                                          during gestation &
                                                                                          lactation male &
                                                                                          female. In addition
                                                                                          decreased food
                                                                                          consumption in females
                                                                                          and hydro-nephritic
                                                                                          kidneys in males.
                                       Dermal Absorption =
                                        100%
                                       Inhalation absorption =
                                        100%
----------------------------------------------------------------------------------------------------------------
* The reference to the FQPA Safety Factor refers to any additional safety factor retained due to concerns unique
  to the FQPA.

C. Exposure Assessment

    1. Dietary exposure from food and feed uses. Tolerances have been 
established (40 CFR 180.425) for the residues of clomazone, in or on a 
variety of raw agricultural commodities. Risk assessments were 
conducted by EPA to assess dietary exposures from clomazone in food as 
follows:
    i. Acute exposure. Acute dietary risk assessments are performed for 
a food-use pesticide if a toxicological study has indicated the 
possibility of an effect of concern occurring as a result of a one day 
or single exposure. The Dietary Exposure Evaluation Model (DEEM) 
analysis evaluated the individual food consumption as reported by 
respondents in the USDA 1989-1992 nationwide Continuing Surveys of Food 
Intake by Individuals (CSFII) and accumulated exposure to the chemical 
for each commodity. The following assumptions were made for the acute 
exposure assessments: A Tier 1 acute analysis was performed for females 
13-50 years old using existing and recommended tolerance level 
residues, 100% crop treated.
    ii. Chronic exposure. In conducting this chronic dietary risk 
assessment the DEEM analysis evaluated the individual food consumption 
as reported by respondents in the USDA (1989-1992) nationwide CSFII and 
accumulated exposure to the chemical for each commodity. The following 
assumptions were made for the chronic exposure assessments: A Tier 1 
chronic analysis was performed for the general U.S. population and all 
population subgroups using existing and recommended tolerance level 
residues, 100% crop treated.
    2. Dietary exposure from drinking water. The Agency lacks 
sufficient monitoring exposure data to complete a comprehensive dietary 
exposure analysis and risk assessment for clomazone in drinking water. 
Because the Agency does not have comprehensive monitoring data, 
drinking water concentration estimates are made by reliance on 
simulation or modeling taking into account data on the physical 
characteristics of clomazone. Clomazone's major environmental 
degradate, FMC 65317 (N-[2- chlorophenol)methyl] -3-hydroxy-2,2-
dimethyl propanamide) was also included in the drinking water 
assessment.
    The Agency uses the Generic Estimated Environmental Concentration 
(GENEEC) or the Pesticide Root Zone/Exposure Analysis Modeling System 
(PRZM/EXAMS) to estimate pesticide concentrations in surface water and 
screening concentration in ground water (SCI-GROW), which predicts 
pesticide concentrations in ground water. In general, EPA will use 
GENEEC (a tier 1 model) before using PRZM/EXAMS (a tier 2 model) for a 
screening-level assessment for surface water. The GENEEC model is a 
subset of the PRZM/EXAMS model that uses a specific high-end runoff 
scenario for pesticides. GENEEC incorporates a farm pond scenario, 
while PRZM/EXAMS incorporate an index reservoir environment in place of 
the previous pond scenario. The PRZM/EXAMS model includes a percent 
crop area factor as an adjustment to account for the maximum percent 
crop coverage within a watershed or drainage basin.
    None of these models include consideration of the impact processing 
(mixing, dilution, or treatment) of raw water for distribution as 
drinking water would likely have on the removal of pesticides from the 
source water. The primary use of these models by the Agency at this 
stage is to provide a coarse screen for sorting out pesticides for 
which it is highly unlikely that drinking water concentrations would 
ever exceed human health levels of concern.
    Since the models used are considered to be screening tools in the 
risk assessment process, the Agency does not use estimated 
environmental concentrations (EECs) from these models to quantify 
drinking water exposure and risk as a %RfD or %PAD. Instead drinking 
water levels of comparison (DWLOCs) are calculated and used as a point 
of comparison against the model estimates of a pesticide's 
concentration in water. DWLOCs are theoretical upper limits on a 
pesticide's concentration in drinking water in light of total aggregate 
exposure to a pesticide in food, and from residential uses. Since 
DWLOCs address

[[Page 10201]]

total aggregate exposure to clomazone they are further discussed in the 
aggregate risk sections below.
    Based on the GENEEC and SCI-GROW models the EECs of clomazone and 
FMC 65317 for acute exposures are estimated to be 95 parts per billion 
(ppb) for surface water and 2.4 ppb for ground water. The EECs for 
chronic exposures are estimated to be 23 ppb for surface water and 2.4 
ppb for ground water.
    3. From non-dietary exposure. The term ``residential exposure'' is 
used in this document to refer to non-occupational, non-dietary 
exposure (e.g., for lawn and garden pest control, indoor pest control, 
termiticides, flea and tick control on pets).
    Clomazone is not registered for use on any sites that would result 
in residential exposure.
    4. Cumulative exposure to substances with a common mechanism of 
toxicity. Section 408(b)(2)(D)(v) requires that, when considering 
whether to establish, modify, or revoke a tolerance, the Agency 
consider ``available information'' concerning the cumulative effects of 
a particular pesticide's residues and ``other substances that have a 
common mechanism of toxicity.''
    EPA does not have, at this time, available data to determine 
whether clomazone has a common mechanism of toxicity with other 
substances or how to include this pesticide in a cumulative risk 
assessment. Unlike other pesticides for which EPA has followed a 
cumulative risk approach based on a common mechanism of toxicity, 
clomazone does not appear to produce a toxic metabolite produced by 
other substances. For the purposes of this tolerance action, therefore, 
EPA has not assumed that clomazone has a common mechanism of toxicity 
with other substances. For information regarding EPA's efforts to 
determine which chemicals have a common mechanism of toxicity and to 
evaluate the cumulative effects of such chemicals, see the final rule 
for Bifenthrin Pesticide Tolerances (62 FR 62961, November 26, 1997).

D. Safety Factor for Infants and Children

    1. Safety factor for infants and children--i. In general. FFDCA 
section 408 provides that EPA shall apply an additional tenfold margin 
of safety for infants and children in the case of threshold effects to 
account for prenatal and postnatal toxicity and the completeness of the 
data base on toxicity and exposure unless EPA determines that a 
different margin of safety will be safe for infants and children. 
Margins of safety are incorporated into EPA risk assessments either 
directly through use of a margin of exposure (MOE) analysis or through 
using uncertainty (safety) factors in calculating a dose level that 
poses no appreciable risk to humans.
    ii. Prenatal and postnatal sensitivity. The prenatal and postnatal 
toxicology data base for clomazone is complete with respect to FQPA 
considerations. There is no quantitative or qualitative evidence of 
increased susceptibility of rats or rabbit fetuses to in utero exposure 
in developmental studies. Although there was a suggestion of 
susceptibility in the rat developmental study based on the presence of 
delayed ossification in the fetuses, the EPA concluded that the fetal 
effects were no more severe than the maternal effects because: There is 
no dose response relationship for delayed ossification (i.e., absence 
of increased incidence with increase in dose); low fetal/litter 
incidences; delayed ossifications were not considered to be severe; and 
no visceral or skeletal malformations were seen.
    iii. Conclusion. There is a complete toxicity data base for 
clomazone and exposure data are complete or are estimated based on data 
that reasonably accounts for potential exposures. The FQPA factor was 
reduced to 1X because of the following reasons: There is no indication 
of quantitative or qualitative increased susceptibility of rats or 
rabbits to in utero and/or postnatal exposure; a developmental 
neurotoxicity study is not required; and the dietary (food and drinking 
water) exposure assessments will not under estimate the potential 
exposures for infants and children (there are currently no registered 
residential uses).

E. Aggregate Risks and Determination of Safety

    To estimate total aggregate exposure to a pesticide from food, 
drinking water, and residential uses, the Agency calculates DWLOCs 
which are used as a point of comparison against the model estimates of 
a pesticide's concentration in water (EECs). DWLOC values are not 
regulatory standards for drinking water. DWLOCs are theoretical upper 
limits on a pesticide's concentration in drinking water in light of 
total aggregate exposure to a pesticide in food and residential uses. 
In calculating a DWLOC, the Agency determines how much of the 
acceptable exposure (i.e., the PAD) is available for exposure through 
drinking water (e.g., allowable chronic water exposure (mg/kg/day) = 
cPAD - (average food + residential exposure)). This allowable exposure 
through drinking water is used to calculate a DWLOC.
    A DWLOC will vary depending on the toxic endpoint, drinking water 
consumption, and body weights. Default body weights and consumption 
values as used by the US EPA Office of Water are used to calculate 
DWLOCs: 2Liters (L)/70kilograms (kg) (adult male), 2L/60 kg (adult 
female), and 1L/10 kg (child). Default body weights and drinking water 
consumption values vary on an individual basis. This variation will be 
taken into account in more refined screening-level and quantitative 
drinking water exposure assessments. Different populations will have 
different DWLOCs. Generally, a DWLOC is calculated for each type of 
risk assessment used: Acute, short-term, intermediate-term, chronic, 
and cancer.
    When EECs for surface water and ground water are less than the 
calculated DWLOCs, OPP concludes with reasonable certainty that 
exposures to the pesticide in drinking water (when considered along 
with other sources of exposure for which OPP has reliable data) would 
not result in unacceptable levels of aggregate human health risk at 
this time. Because OPP considers the aggregate risk resulting from 
multiple exposure pathways associated with a pesticide's uses, levels 
of comparison in drinking water may vary as those uses change. If new 
uses are added in the future, OPP will reassess the potential impacts 
of residues of the pesticide in drinking water as a part of the 
aggregate risk assessment process.
    1. Acute risk. A Tier 1 acute dietary exposure analysis for 
clomazone was performed using existing and proposed tolerance level 
residues, 100 CT for all commodities, and DEEM default processing 
factors. The acute analysis was performed for females 13-50 years old. 
Using the exposure assumptions discussed in this unit for acute 
exposure, the acute dietary exposure from food to clomazone will occupy 
1% of aPAD for females 13-50 years and older at the 95th percentile. In 
addition, there is potential for acute dietary exposure to clomazone in 
drinking water. After calculating DWLOCs and comparing them to the EECs 
for surface and ground water, EPA does not expect the aggregate 
exposure to exceed 100% of the aPAD, as shown in the following Table 3:

[[Page 10202]]



                       Table 3.--Aggregate Risk Assessment for Acute Exposure to Clomazone
----------------------------------------------------------------------------------------------------------------
                                   aPAD, mg/kg/                        Surface Water,      Ground
   Scenario/Population Subgroup         day         % aPAD (Food)           ppb          Water, ppb   DWLOC ppb
----------------------------------------------------------------------------------------------------------------
Females 13-50 yrs old                          1                 1%                 95          2.4       30,000
----------------------------------------------------------------------------------------------------------------

    2. Chronic risk. A Tier 1 chronic dietary exposure analysis for 
clomazone was performed using existing and proposed tolerance level 
residues, 100% CT for all commodities, and DEEM default processing 
factors. The chronic analysis applied to the U.S. population and all 
population subgroups. Using the exposure assumptions described in this 
unit for chronic exposure, EPA has concluded that exposure to clomazone 
from food will utilize 1% of the cPAD for the U.S. population and all 
population subgroups. There are no residential uses for clomazone that 
result in chronic residential exposure to clomazone. After calculating 
DWLOCs and comparing them to the EECs for surface and ground water, EPA 
does not expect the aggregate exposure to exceed 100% of the cPAD, as 
shown in the following Table 4:

              Table 4. -- Aggregate Risk Assessment for Chronic (Non-Cancer) Exposure to Clomazone
----------------------------------------------------------------------------------------------------------------
                                   cPAD, mg/kg/                        Surface Water,      Ground
  Scenario/Population Subgroup          day         % cPAD (Food)           ppb          Water, ppb   DWLOC, ppb
----------------------------------------------------------------------------------------------------------------
U.S. Population                             0.84                  1                 23          2.4       29,000
----------------------------------------------------------------------------------------------------------------
All infants ( 1 year old)                   0.84                  1                 23          2.4        8,400
----------------------------------------------------------------------------------------------------------------
Children (1-6 years old)                    0.84                  1                 23          2.4        8,400
----------------------------------------------------------------------------------------------------------------
Children (7-12 years old)                   0.84                  1                 23          2.4        8,400
----------------------------------------------------------------------------------------------------------------
Females (13-50 years old)                   0.84                  1                 23          2.4       25,000
----------------------------------------------------------------------------------------------------------------

    3. Short- and intermediate- term risk. Short-and intermediate-term 
aggregate exposure takes into account residential exposure plus chronic 
exposure to food and water (considered to be a background exposure 
level).
    Clomazone is not registered for use on any sites that would result 
in residential exposure. Therefore, the aggregate risk is the sum of 
the risk from food and water, which do not exceed the Agency's level of 
concern.
    4. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
to the general population, and to infants and children from aggregate 
exposure to clomazone residues.

IV. Other Considerations

A. Analytical Enforcement Methodology

    Adequate enforcement methods are available for the determination of 
the residues of clomazone in plants. Briefly, samples are acid 
hydrolyzed, hexane extracted, Na2CO3 washed, and 
cleaned-up with a FlorisilR column. The resulting samples are analyzed 
by gas chromatography (GC) using a nitrogen phosphorus detector (NPD) 
or mass spectrometer (MS). The limit of quantitation (LOQ) for this 
method is 0.05 ppm. A confirmatory procedure (GC/MS-SIM) is available 
(Method I, PAM II).

B. International Residue Limits

    There is neither a Codex proposal, nor Canadian or Mexican limits 
for residues of clomazone in/on the subject crops. Therefore, a 
compatibility issue is not relevant to the proposed tolerance.

V. Conclusion

    Therefore, tolerances are established for residues of clomazone, 
[2-(2-chlorophenyl)methyl-4,4-dimethyl-3-isoxazolidinone], in or on the 
tuberous and corm vegetable (except potato) crop subgroup and cucurbit 
vegetable crop group at 0.05 ppm.

VI. Objections and Hearing Requests

    Under section 408(g) of the FFDCA, as amended by the FQPA, any 
person may file an objection to any aspect of this regulation and may 
also request a hearing on those objections. The EPA procedural 
regulations which govern the submission of objections and requests for 
hearings appear in 40 CFR part 178. Although the procedures in those 
regulations require some modification to reflect the amendments made to 
the FFDCA by the FQPA of 1996, EPA will continue to use those 
procedures, with appropriate adjustments, until the necessary 
modifications can be made. The new section 408(g) provides essentially 
the same process for persons to ``object'' to a regulation for an 
exemption from the requirement of a tolerance issued by EPA under new 
section 408(d), as was provided in the old FFDCA sections 408 and 409. 
However, the period for filing objections is now 60 days, rather than 
30 days.

A. What Do I Need to Do to File an Objection or Request a Hearing?

    You must file your objection or request a hearing on this 
regulation in accordance with the instructions provided in this unit 
and in 40 CFR part 178. To ensure proper receipt by EPA, you must 
identify docket control number OPP-301101 in the subject line on the 
first page of your submission. All requests must be in writing, and 
must be mailed or delivered to the Hearing Clerk on or before April 16, 
2001.
    1. Filing the request. Your objection must specify the specific 
provisions in the regulation that you object to, and the grounds for 
the objections (40 CFR 178.25). If a hearing is requested, the 
objections must include a statement of the factual issues(s) on which a 
hearing is requested, the requestor's contentions on such issues, and a 
summary of any evidence relied upon by the objector (40 CFR 178.27). 
Information submitted in connection with an objection or hearing 
request may be claimed confidential by marking any part or all of that 
information as CBI. Information so marked will not be disclosed except 
in accordance with procedures set forth in 40 CFR part 2. A copy of the 
information that does not contain CBI

[[Page 10203]]

must be submitted for inclusion in the public record. Information not 
marked confidential may be disclosed publicly by EPA without prior 
notice.
    Mail your written request to: Office of the Hearing Clerk (1900), 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460. You may also deliver your request to the Office 
of the Hearing Clerk in Rm. C400, Waterside Mall, 401 M St., SW., 
Washington, DC 20460. The Office of the Hearing Clerk is open from 8 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
telephone number for the Office of the Hearing Clerk is (202) 260-4865.
    2. Tolerance fee payment. If you file an objection or request a 
hearing, you must also pay the fee prescribed by 40 CFR 180.33(i) or 
request a waiver of that fee pursuant to 40 CFR 180.33(m). You must 
mail the fee to: EPA Headquarters Accounting Operations Branch, Office 
of Pesticide Programs, P.O. Box 360277M, Pittsburgh, PA 15251. Please 
identify the fee submission by labeling it ``Tolerance Petition Fees.''
    EPA is authorized to waive any fee requirement ``when in the 
judgement of the Administrator such a waiver or refund is equitable and 
not contrary to the purpose of this subsection.'' For additional 
information regarding the waiver of these fees, you may contact James 
Tompkins by phone at (703) 305-5697, by e-mail at tompkins.jim@epa.gov, 
or by mailing a request for information to Mr. Tompkins at Registration 
Division (7505C), Office of Pesticide Programs, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
    If you would like to request a waiver of the tolerance objection 
fees, you must mail your request for such a waiver to: James Hollins, 
Information Resources and Services Division (7502C), Office of 
Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460.
    3. Copies for the Docket. In addition to filing an objection or 
hearing request with the Hearing Clerk as described in Unit VI.A., you 
should also send a copy of your request to the PIRIB for its inclusion 
in the official record that is described in Unit I.B.2. Mail your 
copies, identified by docket control number OPP-301101, to: Public 
Information and Records Integrity Branch, Information Resources and 
Services Division (7502C), Office of Pesticide Programs, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460. 
In person or by courier, bring a copy to the location of the PIRIB 
described in Unit I.B.2. You may also send an electronic copy of your 
request via e-mail to: opp-docket@epa.gov. Please use an ASCII file 
format and avoid the use of special characters and any form of 
encryption. Copies of electronic objections and hearing requests will 
also be accepted on disks in WordPerfect 6.1/8.0 or ASCII file format. 
Do not include any CBI in your electronic copy. You may also submit an 
electronic copy of your request at many Federal Depository Libraries.

B. When Will the Agency Grant a Request for a Hearing?

    A request for a hearing will be granted if the Administrator 
determines that the material submitted shows the following: There is a 
genuine and substantial issue of fact; 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; and resolution of the factual issues(s) in the manner sought 
by the requestor would be adequate to justify the action requested (40 
CFR 178.32).

VII. Regulatory Assessment Requirements

    This final rule establishes a tolerance under FFDCA section 408(d) 
in response to a petition submitted to the Agency. The Office of 
Management and Budget (OMB) has exempted these types of actions from 
review under Executive Order 12866, entitled Regulatory Planning and 
Review (58 FR 51735, October 4, 1993). This final rule does not contain 
any information collections subject to OMB approval under the Paperwork 
Reduction Act (PRA), 44 U.S.C. 3501 et seq., or impose any enforceable 
duty or contain any unfunded mandate as described under Title II of the 
Unfunded Mandates Reform Act of 1995 (UMRA) (Public Law 104-4). Nor 
does it require any prior consultation as specified by Executive Order 
13084, entitled Consultation and Coordination with Indian Tribal 
Governments (63 FR 27655, May 19, 1998); special considerations as 
required by Executive Order 12898, entitled Federal Actions to Address 
Environmental Justice in Minority Populations and Low-Income 
Populations (59 FR 7629, February 16, 1994); or require OMB review or 
any Agency action under Executive Order 13045, entitled Protection of 
Children from Environmental Health Risks and Safety Risks (62 FR 19885, 
April 23, 1997). This action does not involve any technical standards 
that would require Agency consideration of voluntary consensus 
standards pursuant to section 12(d) of the National Technology Transfer 
and Advancement Act of 1995 (NTTAA), Public Law 104-113, section 12(d) 
(15 U.S.C. 272 note). Since tolerances and exemptions that are 
established on the basis of a petition under FFDCA section 408(d), such 
as the tolerance in this final rule, do not require the issuance of a 
proposed rule, the requirements of the Regulatory Flexibility Act (RFA) 
(5 U.S.C. 601 et seq.) do not apply. In addition, the Agency has 
determined that this action will not have a substantial direct effect 
on States, on the relationship between the national government and the 
States, or on the distribution of power and responsibilities among the 
various levels of government, as specified in Executive Order 13132, 
entitled Federalism (64 FR 43255, August 10, 1999). Executive Order 
13132 requires EPA to develop an accountable process to ensure 
``meaningful and timely input by State and local officials in the 
development of regulatory policies that have federalism implications.'' 
``Policies that have federalism implications'' is defined in the 
Executive Order to include regulations that have ``substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government.'' This final 
rule directly regulates growers, food processors, food handlers and 
food retailers, not States. This action does not alter the 
relationships or distribution of power and responsibilities established 
by Congress in the preemption provisions of FFDCA section 408(n)(4).

VIII. 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, generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report, which includes a copy of the rule, 
to each House of the Congress and to the Comptroller General of the 
United States. EPA will submit a report containing this rule and other 
required information to the U.S. Senate, the U.S. House of 
Representatives, and the Comptroller General of the United States prior 
to publication of this final rule in the Federal Register. This final 
rule is not a ``major rule'' as defined by 5 U.S.C. 804(2).

List of Subjects in 40 CFR Part 180

    Environmental protection, Administrative practice and procedure, 
Agricultural commodities, Pesticides

[[Page 10204]]

and pests, Reporting and recordkeeping requirements.


    Dated: January 18, 2001.

James Jones,
Director, Registration Division, Office of Pesticide Programs.

    Therefore, 40 CFR chapter I is amended as follows:

PART 180--[AMENDED]

    1. The authority citation for part 180 continues to read as 
follows:

    Authority:  21 U.S.C. 321(q), 346(a) and 371.

    2. Section 180.425 is amended by alphabetically adding commodities 
to the table in paragraph (a) to read as follows:


Sec. 180.425  Clomazone; tolerances for residues.

    (a) General.*  *  *

------------------------------------------------------------------------
                                                              Parts per
                         Commodity                             million
------------------------------------------------------------------------
              *        *        *        *        *
Vegetable, cucurbit, group.................................         0.05
Vegetable, tuberous and corm, except potato, subgroup......         0.05
------------------------------------------------------------------------

* * * * *

[FR Doc. 01-3619 Filed 2-13-01; 8:45 am]
BILLING CODE 6560-50-S 

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