Pyridate; Pesticide Tolerances for Emergency Exemptions

Note: EPA no longer updates this information, but it may be useful as a reference or resource.
 [Federal Register: August 25, 1999 (Volume 64, Number 164)]
[Rules and Regulations]               
[Page 46292-46298]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr25au99-20]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[OPP-300905; FRL-6094-7]
RIN 2070-AB78

 
Pyridate; Pesticide Tolerances for Emergency Exemptions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes time-limited tolerances for 
combined residues of pyridate (O-(6-chloro-3-phenyl-4-pyridazinyl)-S-
octyl-carbonothioate), the metabolite 6-chloro-3-phenyl-pyridazine-4-ol 
and conjugates of 6-chloro-3-phenyl-pyridazine-4-ol in or on peppermint 
tops (leaves and stems) and spearmint tops (leaves and stems). This 
action is in response to EPA's granting of an emergency exemption under 
section 18 of the Federal Insecticide, Fungicide, and Rodenticide Act 
authorizing use of the pesticide on peppermint and spearmint. This 
regulation establishes a maximum permissible level for residues of 
pyridate in these food commodities pursuant to section 408(l)(6) of the 
Federal Food, Drug, and Cosmetic Act, as amended by the Food Quality 
Protection Act of 1996. The tolerances will expire and are revoked on 
December 31, 2001.

DATES: This regulation is effective August 25, 1999. Objections and 
requests for hearings must be received by EPA on or before October 25, 
1999.

ADDRESSES: Written objections and hearing requests, identified by the 
docket control number [OPP-300905], must be submitted to: Hearing Clerk 
(1900), Environmental Protection Agency, Rm. M3708, 401 M St., SW., 
Washington, DC 20460. Fees accompanying objections and hearing requests 
shall be labeled ``Tolerance Petition Fees'' and forwarded to: EPA 
Headquarters Accounting Operations Branch, OPP (Tolerance Fees), P.O. 
Box 360277M, Pittsburgh, PA 15251. A copy of any objections and hearing 
requests filed with the Hearing Clerk identified by the docket control 
number, [OPP-300905], must also be submitted to: Public Information and 
Records Integrity Branch, Information Resources and Services Division 
(7502C), Office of Pesticide Programs, Environmental Protection Agency, 
401 M St., SW., Washington, DC 20460. In person, bring a copy of 
objections and hearing requests to Rm. 119, Crystal Mall 2 (CM #2), 
1921 Jefferson Davis Hwy., Arlington, VA.
    A copy of objections and hearing requests filed with the Hearing 
Clerk may also be submitted electronically by sending electronic mail 
(e-mail) to: opp-docket@epa.gov. Copies of electronic objections and 
hearing requests must be submitted as an ASCII file avoiding the use of 
special characters and any form of encryption. Copies of objections and 
hearing requests will also be accepted on disks in WordPerfect 5.1/6.1 
or ASCII file format. All copies of electronic objections and hearing 
requests must be identified by the docket control number [OPP-300905]. 
No Confidential Business Information (CBI) should be submitted through 
e-mail. Copies of electronic objections and hearing requests on this 
rule may be filed online at many Federal Depository Libraries.

FOR FURTHER INFORMATION CONTACT: By mail: Barbara Madden, Registration 
Division (7505C), Office of Pesticide Programs, Environmental 
Protection Agency, 401 M St., SW., Washington, DC 20460. Office 
location, telephone number, and e-mail address: Rm. 284, CM #2, 1921 
Jefferson Davis Hwy., Arlington, VA, (703) 305-6463, 
Madden.Barbara@epa.gov.

SUPPLEMENTARY INFORMATION: EPA, on its own initiative, pursuant to 
section 408(l)(6) of the Federal Food, Drug, and Cosmetic Act (FFDCA), 
21 U.S.C. 346a,

[[Page 46293]]

is establishing tolerances for combined residues of the herbicide 
pyridate (O-(6-chloro-3-phenyl-4-pyridazinyl)-S-octyl-carbonothioate, 
the metabolite 6-chloro-3-phenyl-pyridazine-4-ol and conjugates of 6-
chloro-3-phenyl-pyridazine-4-ol, in or on peppermint tops (leaves and 
stems) and spearmint tops (leaves and stems) at 0.3 part per million 
(ppm). These tolerances will expire and are revoked on December 31, 
2001. EPA will publish a document in the Federal Register to remove the 
revoked tolerance from the Code of Federal Regulations.

I. Background and Statutory Findings

    The Food Quality Protection Act of 1996 (FQPA) (Public Law 104-170) 
was signed into law August 3, 1996. FQPA amends both the FFDCA, 21 
U.S.C. 301 et seq., and the Federal Insecticide, Fungicide, and 
Rodenticide Act (FIFRA), 7 U.S.C. 136 et seq. The FQPA amendments went 
into effect immediately. Among other things, FQPA amends FFDCA to bring 
all EPA pesticide tolerance-setting activities under a new section 408 
with a new safety standard and new procedures. These activities are 
described in this preamble and discussed in greater detail in the final 
rule establishing the time-limited tolerance associated with the 
emergency exemption for use of propiconazole on sorghum (61 FR 58135, 
November 13, 1996) (FRL-5572-9).
    New 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. . . .''
    Section 18 of FIFRA authorizes EPA to exempt any Federal or State 
agency from any provision of FIFRA, if EPA determines that ``emergency 
conditions exist which require such exemption.'' This provision was not 
amended by FQPA. EPA has established regulations governing such 
emergency exemptions in 40 CFR part 166.
    Section 408(l)(6) of the FFDCA requires EPA to establish a time-
limited tolerance or exemption from the requirement for a tolerance for 
pesticide chemical residues in food that will result from the use of a 
pesticide under an emergency exemption granted by EPA under section 18 
of FIFRA. Such tolerances can be established without providing notice 
or period for public comment.
    Because decisions on section 18-related tolerances must proceed 
before EPA reaches closure on several policy issues relating to 
interpretation and implementation of the FQPA, EPA does not intend for 
its actions on such tolerances to set binding precedents for the 
application of section 408 and the new safety standard to other 
tolerances and exemptions.

II. Emergency Exemption for Pyridate on Peppermint and Spearmint 
and FFDCA Tolerances

    Redroot pigweed and kochia have become serious pest concerns for 
Idaho, Indiana, Montana, Oregon, Washington and Wisconsin mint growers. 
The lack of any post-emergence chemical weed control have created an 
emergency situation. Currently, terbacil is the only herbicide 
registered for post-emergence weed control in mint, but resistance of 
pigweed and kochia has been well documented. Not only will the presence 
of these weeds result in mint yield losses but mint oil quality is 
adversely effected as well. EPA has authorized under FIFRA section 18 
the use of pyridate on peppermint and spearmint for control of redroot 
pigweed and kochia in Idaho, Indiana, Montana, Oregon, Washington and 
Wisconsin. After having reviewed the submission, EPA concurs that 
emergency conditions exist for these States.
    As part of its assessment of this emergency exemption, EPA assessed 
the potential risks presented by residues of pyridate in or on 
peppermint and spearmint. In doing so, EPA considered the safety 
standard in FFDCA section 408(b)(2), and EPA decided that the necessary 
tolerance under FFDCA section 408(l)(6) would be consistent with the 
safety standard and with FIFRA section 18. Consistent with the need to 
move quickly on the emergency exemption in order to address an urgent 
non-routine situation and to ensure that the resulting food is safe and 
lawful, EPA is issuing this tolerance without notice and opportunity 
for public comment under section 408(e), as provided in section 
408(l)(6). Although these tolerances will expire and are revoked on 
December 31, 2001, under FFDCA section 408(l)(5), residues of the 
pesticide not in excess of the amounts specified in the tolerance 
remaining in or on peppermint and spearmint after that date will not be 
unlawful, provided the pesticide is applied in a manner that was lawful 
under FIFRA, and the residues do not exceed a level that was authorized 
by this tolerance at the time of that application. EPA will take action 
to revoke these tolerances earlier if any experience with, scientific 
data on, or other relevant information on this pesticide indicate that 
the residues are not safe.
    Because these tolerances are being approved under emergency 
conditions, EPA has not made any decisions about whether pyridate meets 
EPA's registration requirements for use on peppermint and spearmint or 
whether permanent tolerances for these uses would be appropriate. Under 
these circumstances, EPA does not believe that these tolerances serve 
as a basis for registration of pyridate by a State for special local 
needs under FIFRA section 24(c). Nor does this tolerance serve as the 
basis for any State other than Idaho, Indiana, Montana, Oregon, 
Washington and Wisconsin to use this pesticide on these crops under 
section 18 of FIFRA without following all provisions of EPA's 
regulations implementing section 18 as identified in 40 CFR part 166. 
For additional information regarding the emergency exemption for 
pyridate, contact the Agency's Registration Division at the address 
provided under the ``ADDRESSES'' section.

III. Aggregate Risk Assessment and Determination of Safety

    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) .
    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 pyridate 
and to make a determination on aggregate exposure, consistent with 
section 408(b)(2), for time-limited tolerances for combined residues of 
pyridate (O-(6-chloro-3-phenyl-4-pyridazinyl)-S-octyl-carbonothioate), 
the metabolite 6-chloro-3-phenyl-pyridazine-4-ol and conjugates of 6-
chloro-3-phenyl-

[[Page 46294]]

pyridazine-4-ol on peppermint and spearmint at 0.3 ppm. EPA's 
assessment of the dietary 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 pyridate are 
discussed in this unit.

B. Toxicological Endpoint

    1. Acute toxicity. An acute dietary reference dose (acute RfD) of 
0.20 milligrams/kilograms/day (mg/kg/day) has been identified. The 
acute RfD is derived from the systemic no observable adverse effects 
level (NOAEL) of 20 mg/kg/day based on neurotoxic effects (ataxia and 
emesis) seen at the lowest observable adverse effects level (LOAEL) of 
60 mg/kg/day in the 90-day feeding study in dogs and an uncertainty 
factor of 100 (10x for interspecies differences and 10x for 
intraspecies variations). EPA has determined that the 10x factor to 
account for enhanced susceptibility of infants and children, as 
required by FFDCA section 408(b)(2)(C), can be removed. The acute 
Population Adjusted Dose (aPAD) is a modification of the acute RfD to 
accommodate the FQPA Safety Factor. The aPAD is equal to the acute RfD 
divided by the FQPA Safety Factor. Therefore, since EPA has determined 
that the 10x factor to account for enhanced susceptibility of infants 
and children can be removed, the aPAD and acute RfD are the same (0.20 
mg/kg/day).
    2. Short- and intermediate-term toxicity. For short- and 
intermediate-term dermal and inhalation exposures, the systemic NOAEL 
of 20 mg/kg/day from the 90-day feeding study in dogs based on clinical 
signs of neurotoxicity at the LOAEL of 60 mg/kg/day was identified as 
the short- and intermediate-term endpoint to be used in risk 
assessments. Since an oral dose was selected for dermal risk 
assessments, the Agency has determined that a dermal penetration factor 
of 20% is appropriate. The same oral dose (20 mg/kg/day) was also 
selected for inhalation risk assessments. Therefore, for inhalation 
exposure the following are appropriate: (i) Converting inhalation 
exposure in mg/Liter (L) to mg/kg/day (route-to-route extrapolation 
using 100% inhalation absorption); (ii) combining the converted 
exposure with dermal exposure (using 20% dermal absorption) and (iii) 
comparing the combined total to the appropriate oral NOAEL chosen for 
the short- and intermediate-term exposure scenario (NOAEL = 20 mg/kg/
day).
    3. Chronic toxicity. EPA has established the chronic RfD for 
pyridate at 0.11 mg/kg/day. This chronic RfD is derived from a NOAEL of 
10.8 mg/kg/day based on decreased body weight gain in males seen at 
67.5 mg/kg/day (LOAEL) in a 2-year feeding study in rats and an 
uncertainty factor of 100 (10x for interspecies differences and 10x for 
intraspecies variations). EPA has determined that the 10x factor to 
account for enhanced susceptibility of infants and children, as 
required by FFDCA section 408(b)(2)(C), can be removed. The chronic 
Population Adjusted Dose (cPAD) is a modification of the chronic RfD to 
accommodate the FQPA Safety Factor. The cPAD is equal to the chronic 
RfD divided by the FQPA Safety Factor. Therefore since the EPA has 
determined that the 10x factor to account for enhanced susceptibility 
of infants and children can be removed, the cPAD and chronic RfD are 
the same (0.11 mg/kg/day).
    For chronic dermal and inhalation exposures, the NOAEL of 10.8 mg/
kg/day from a 2-year feeding study in rats based on decreased body 
weight gain at the LOAEL of 67.5 mg/kg/day, was identified as the 
chronic endpoint to be used in dermal and inhalation risk assessments. 
Since an oral dose was selected for dermal risk assessments, the Agency 
has determined that a dermal penetration rate of 20% is appropriate. 
The same oral dose (20 mg/kg/day) was also selected for chronic 
inhalation risk assessments. Therefore, for inhalation exposure the 
following are appropriate: (i) Converting inhalation exposure in mg/L 
to mg/kg/day (route-to-route extrapolation using 100% inhalation 
absorption); (ii) combining the converted exposure with dermal exposure 
(using 20% dermal absorption); and (iii) comparing the combined total 
to the appropriate oral NOAEL chosen for the chronic exposure scenario 
(NOAEL = 10.8 mg/kg/day).
    4. Carcinogenicity. Pyridate has not been designated a cancer 
classification by the Agency to date. However, there is no evidence of 
a tumorigenic response in the 2-year rat feeding study and the mouse 
carcinogenicity study with pyridate.

C. Exposures and Risks

    1. From food and feed uses. Tolerances have been established (40 
CFR 180.462) for the combined residues of pyridate (O-(6-chloro-3-
phenyl-4-pyridazinyl)-S-octyl-carbonothioate, the metabolite 6-chloro-
3-phenyl-pyridazine-4-ol and conjugates of 6-chloro-3-phenyl-
pyridazine-4-ol, in or on cabbage, corn, and peanuts. Risk assessments 
were conducted by EPA to assess dietary exposures and risks from 
pyridate as follows:
    i.  Acute exposure and risk. 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 1-day or single exposure. The Dietary Exposure Evaluation Model 
(DEEM) analysis evaluated the individual food consumption as reported 
by respondents in the USDA 1989-91 nationwide Continuing Surveys of 
Food Intake by Individuals (CSFII) and accumulated exposure to the 
chemical for each commodity. At the 95th percentile exposure level, 
assuming 100 percent crop treated (PCT) and tolerance level residues 
for all commodities, less than 1% of the aPAD was utilized for the U.S. 
Population and children (1-6 years old), the subgroup with the highest 
exposure. The results of this analysis indicate that the acute dietary 
risk associated with existing uses and the proposed use of pyridate is 
below the Agency's level of concern.
    ii. Chronic exposure and risk. In conducting chronic dietary risk 
assessments, the following conservative assumptions have been made: (a) 
all of the crops having pyridate tolerances will contain pyridate 
residues and (b) those residues will be at the level of the tolerance. 
This results in an overestimation of human dietary exposure. Thus, in 
making safety determinations for the peppermint and spearmint 
tolerances, the Agency is taking into account these conservative 
exposure assumptions. The combined pyridate tolerances (currently 
published and the section 18 tolerances established by this action) 
result in a Theoretical Maximum Residue Contribution (TMRC) that is 
less than 1% of the RfD for the U.S. population and all population 
subgroups, including non-nursing infants, the subgroup with the highest 
exposure. The results of this analysis indicate that the chronic 
dietary risk associated with existing uses and the proposed use of 
pyridate is below the Agency's level of concern.
    2. From drinking water. The Agency lacks sufficient water-related 
exposure data to complete a comprehensive

[[Page 46295]]

drinking water exposure analysis and risk assessment for pyridate. 
Because the Agency does not have comprehensive and reliable monitoring 
data, drinking water concentration estimates must be made by reliance 
on some sort of simulation or modeling. To date, there are no validated 
modeling approaches for reliably predicting pesticide levels in 
drinking water. The Agency is currently relying on Generic expected 
environmental concentration (GENEEC) and EPA's Pesticide Root Zone 
Model (PRZM<SUP>3</SUP>)/EXAMS for surface water, which are used to 
produce estimates of pesticide concentrations in a farm pond and 
Screening Concentration in ground water (SCI-GROW), which predicts 
pesticide concentrations in ground water. None of these models include 
consideration of the impact processing 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. Based on the GENEEC and 
SCI-GROW models, the acute drinking water concentration values are 
estimated to be 97 parts per billion (ppb) for surface water and 4.4 
ppb for ground water. The chronic drinking water concentration values 
are estimated to be 25 ppb for surface water and 4.4 pbb for ground 
water.
    In the absence of monitoring data for pesticides, 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, drinking water, and residential uses. A DWLOC will 
vary depending on the toxic endpoint, with drinking water consumption, 
and body weights. Different populations will have different DWLOCs. 
DWLOCs are used in the risk assessment process as a surrogate measure 
of potential exposure associated with pesticide exposure through 
drinking water. DWLOC values are not regulatory standards for drinking 
water. Since DWLOCs address total aggregate exposure to pyridate they 
are further discussed in the aggregate risk sections below.
    3. From non-dietary exposure. Pyridate is not registered on any use 
sites which would result in non-dietary, non-occupational exposure. 
Therefore, EPA expects only dietary and occupational exposure from the 
use of pyridate.
    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 pyridate 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, 
pyridate 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 pyridate has a common mechanism of toxicity 
with other substances. For more 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. Aggregate Risks and Determination of Safety for U.S. Population

    1. Acute risk. Using the exposure assumptions of 100 PCT and 
tolerance level residues for all commodities, at the 95th percentile, 
less than 1% of the aPAD was utilized for the U.S. Population. The 
major identifiable subgroup with the highest aggregate exposure is 
children, 1-6 years old (discussed below). EPA generally has no concern 
for exposures below 100% of the aPAD. Despite the potential for 
exposure to pyridate in drinking water, after calculating a DWLOC 
(7,000 ppb) for the U.S. population and comparing it to conservative 
model estimates of acute concentrations of pyridate in surface and 
ground water (97 ppb and 4.4 pbb, respectively), EPA does not expect 
the aggregate exposure to exceed 100% of the aPAD.
    2. Chronic risk. Using the TMRC exposure assumptions described 
above, EPA has concluded that aggregate exposure to pyridate from food 
will utilize less than 1% of the cPAD for the U.S. population. The 
major identifiable subgroup with the highest aggregate exposure is non-
nursing infants (discussed below). EPA generally has no concern for 
exposures below 100% of the cPAD because the cPAD represents the level 
at or below which daily aggregate dietary exposure over a lifetime will 
not pose appreciable risks to human health. Despite the potential for 
exposure to pyridate in drinking water, after calculating a DWLOC 
(3,800 ppb) for the U.S. population and comparing it to conservative 
model estimates of concentrations of pyridate in surface and ground 
water (25 ppb and 4.4 pbb, respectively), EPA does not expect the 
aggregate exposure to exceed 100% of the cPAD.
    3. Short- and intermediate-term risk. Short- and intermediate-term 
aggregate exposure takes into account chronic dietary food and water 
(considered to be a background exposure level) plus other indoor and 
outdoor non-occupational exposure. Since there are no non-dietary, non-
occupational exposures expected from the use of this chemical, no 
short- and intermediate-term risk assessments were conducted.
    4. Aggregate cancer risk for U.S. population. Pyridate has not been 
designated a cancer classification by the Agency to date. However, 
there is no evidence of a tumorigenic response in the 2-year rat 
feeding study and the mouse carcinogenicity study with pyridate. 
Therefore, no aggregate cancer risk assessments were conducted.
    5. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
from aggregate exposure to pyridate residues.

E. Aggregate Risks and Determination of Safety for Infants and Children

    1. Safety factor for infants and children --i. In general. In 
assessing the potential for additional sensitivity of infants and 
children to residues of pyridate, EPA considered data from 
developmental toxicity studies in the rat and rabbit and a 2-generation 
reproduction study in the rat. The developmental toxicity studies are 
designed to evaluate adverse effects on the developing organism 
resulting from maternal pesticide exposure during gestation. 
Reproduction studies provide information relating to effects from 
exposure to the pesticide on the reproductive capability of mating 
animals and data on systemic toxicity.
    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 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

[[Page 46296]]

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. EPA believes that reliable 
data support using the standard MOE and uncertainty factor (usually 100 
for combined interspecies and intraspecies variability) and not the 
additional tenfold MOE/uncertainty factor when EPA has a complete data 
base under existing guidelines and when the severity of the effect in 
infants or children or the potency or unusual toxic properties of a 
compound do not raise concerns regarding the adequacy of the standard 
MOE/safety factor.
    ii. Developmental toxicity studies. In a prenatal developmental 
toxicity study in rats, the maternal NOAEL was 165 mg/kg/day and the 
LOAEL was 400 mg/kg/day based on mortality, significant decreases in 
mean body weight and food consumption as well as clinical signs 
(ventral body position, dyspnea, sedation, and loss of reaction to 
external stimuli). The developmental NOAEL was 165 mg/kg/day and the 
developmental LOAEL was 400 mg/kg/day, based on increased incidences of 
missing and/or unossified sternebrae and a dose-related decrease in 
mean fetal body weight.
    In a prenatal developmental toxicity study in rabbits, the maternal 
NOAEL was 300 mg/kg/day and the LOAEL was 600 mg/kg/day, based on 
decreased body weight and body weight gain, decreased food consumption, 
increased incidence of dried feces, and increased abortions. For 
developmental toxicity, the NOAEL was equal to or greater than 600 mg/
kg/day, the highest dose tested. A developmental LOAEL was not 
established.
    iii. Reproductive toxicity study. In a 3-generation reproduction 
study in rats, the parental systemic NOAEL was 10.8 mg/kg/day and the 
LOAEL was 67.5 mg/kg/day based on depression of maternal body weight 
gain. The NOAEL for offspring was 10.8 mg/kg/day and the LOAEL was 67.5 
mg/kg/day based on decreased pup weight gains (at postnatal day 14 and 
21 in the first litters for both generations).
    iv. Prenatal and postnatal sensitivity. The toxicological data base 
for evaluating prenatal and postnatal toxicity for pyridate is complete 
with respect to current data requirements. There are no prenatal or 
postnatal toxicity concerns for infants and children, based on the 
results of the rat and rabbit developmental toxicity studies and the 2-
generation rat reproductive toxicity study.
    v. Conclusion. There is a complete toxicity database for pyridate 
and exposure data are complete or are estimated base on data that 
reasonably accounts for potential exposures.The Agency concludes that 
reliable data support use of a 100-fold margin of exposure/uncertainty 
factor, rather than the standard 1,000-fold margin/factor, to protect 
infants and children. Therefore, the 10x factor to account for enhanced 
susceptibility of infants and children, as required by FFDCA section 
408(b)(2)(C), can be removed.
    2. Acute risk. Using the exposure assumptions of 100 PCT and 
tolerance level residues for all commodities, at the 95th percentile, 
less than 1% of the aPAD was utilized for children 1-6 years old, the 
subgroup with the highest aggregate exposure. EPA generally has no 
concern for exposures below 100% of the aPAD. Despite the potential for 
exposure to pyridate in drinking water, after calculating a DWLOC 
(2,000 ppb) children 1-6 years old and comparing it to conservative 
model estimates of acute concentrations of pyridate in surface and 
ground water (97 ppb and 4.4 pbb, respectively), EPA does not expect 
the aggregate exposure to exceed 100% of the aPAD.
    3. Chronic risk. Using the TMRC exposure assumptions described 
above, EPA has concluded that aggregate exposure to pyridate from food 
will utilize less than 1% of the cPAD for infants and children. EPA 
generally has no concern for exposures below 100% of the cPAD because 
the cPAD represents the level at or below which daily aggregate dietary 
exposure over a lifetime will not pose appreciable risks to human 
health. Despite the potential for exposure to pyridate in drinking 
water, after calculating a DWLOC (1,100 ppb) for non-nursing infants, 
the subgroup with the highest aggregate exposure and comparing it to 
conservative model estimates of concentrations of pyridate in surface 
and ground water (25 ppb and 4.4 pbb, respectively), EPA does not 
expect the aggregate exposure to exceed 100% of the cPAD.
    4. Short- or intermediate-term risk. There are no non-dietary, non-
occupational exposures expected from the use of pyridate therefore, no 
short- and intermediate-term risk assessments were conducted.
    5. Determination of safety. Based on these risk assessments, EPA 
concludes that there is a reasonable certainty that no harm will result 
to infants and children from aggregate exposure to pyridate residues.

IV. Other Considerations

A. Metabolism in Plants and Animals

    The nature of the pyridate residue in plants and ruminants is 
adequately understood. The total toxic residue consists of pyridate (O-
(6-chloro-3-phenyl-4-pyridazinyl)-S-octyl-carbonothioate), its 
metabolite 6-chloro-3-phenyl-pyridazine-4-ol, and conjugates of that 
metabolite, all expressed as pyridate.

B. Analytical Enforcement Methodology

    A total residue method using ultraviolet detection/high pressure 
liquid chromatography (UV/HPLC) is available for residue data gathering 
and enforcement purposes. The method has been adequately validated by 
recovery data, has passed a successful method trial, and has been 
forwarded to FDA for publication in PAM-II. The limit of quantitation 
is 0.03 ppm. The method may be requested from: Calvin Furlow, PRRIB, 
IRSD (7502C), Office of Pesticide Programs, Environmental Protection 
Agency, 401 M St., SW., Washington, DC 20460. Office location and 
telephone number: Rm 101FF, CM #2, 1921 Jefferson Davis Hwy., 
Arlington, VA, (703) 305-5229.

C. Magnitude of Residues

    Residues of pyridate, its metabolite 6-chloro-3-phenyl-pyridazine-
4-ol and conjugates of that metabolite all expressed as pyridate are 
not expected to exceed 0.3 ppm in/on peppermint, tops (leaves and 
stems) and spearmint, tops (leaves and stems). Secondary residues are 
not expected in animal commodities as no feed items are associated with 
this section 18 use.

D. International Residue Limits

    There are no CODEX, Mexican, or Canadian MRLs established for 
pyridate in/on mint. Therefore, no compatibility problems exist for the 
proposed tolerances.

E. Rotational Crop Restrictions

    A confined accumulation in rotational crops study with pyridate has 
previously been reviewed. Pyridate residues metabolize rapidly in soil. 
No crop rotation label restrictions are needed.

V. Conclusion

    Therefore, the tolerance is established for combined residues of 
pyridate (O-(6-chloro-3-phenyl-4-pyridazinyl)-S-octyl-carbonothioate), 
the metabolite 6-chloro-3-phenyl-pyridazine-4-ol and conjugates of 6-
chloro-3-phenyl-pyridazine-4-ol in or on peppermint

[[Page 46297]]

tops (leaves and stems) and spearmint tops (leaves and stems) at 0.3 
ppm.

VI. Objections and Hearing Requests

    The new FFDCA section 408(g) provides essentially the same process 
for persons to ``object'' to a tolerance regulation as was provided in 
the old section 408 and in section 409. However, the period for filing 
objections is 60 days, rather than 30 days. EPA currently has 
procedural regulations which govern the submission of objections and 
hearing requests. These regulations will require some modification to 
reflect the new law. However, until those modifications can be made, 
EPA will continue to use those procedural regulations with appropriate 
adjustments to reflect the new law.
    Any person may, by October 25, 1999, file written objections to any 
aspect of this regulation and may also request a hearing on those 
objections. Objections and hearing requests must be filed with the 
Hearing Clerk, at the address given under the ``ADDRESSES'' section (40 
CFR 178.20). A copy of the objections and/or hearing requests filed 
with the Hearing Clerk should be submitted to the OPP docket for this 
rulemaking. The objections submitted must specify the provisions of the 
regulation deemed objectionable and the grounds for the objections (40 
CFR 178.25). Each objection must be accompanied by the fee prescribed 
by 40 CFR 180.33(i). 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 tolerance objection fee waivers, 
contact James Tompkins, Registration Division (7505C), Office of 
Pesticide Programs, Environmental Protection Agency, 401 M St., SW., 
Washington, DC 20460. Office location, telephone number, and e-mail 
address: Rm. 239, CM #2, 1921 Jefferson Davis Hwy., Arlington, VA, 
(703) 305-5697, tompkins.jim@epa.gov. Requests for waiver of tolerance 
objection fees should be sent to James Hollins, Information Resources 
and Services Division (7502C), Office of Pesticide Programs, 
Environmental Protection Agency, 401 M St., SW., Washington, DC 20460.
    If a hearing is requested, the objections must include a statement 
of the factual issues on which a hearing is requested, the requestor's 
contentions on such issues, and a summary of any evidence relied upon 
by the requestor (40 CFR 178.27). A request for a hearing will be 
granted if the Administrator determines that the material submitted 
shows the following: There is 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 in the 
manner sought by the requestor would be adequate to justify the action 
requested (40 CFR 178.32). 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 must be 
submitted for inclusion in the public record. Information not marked 
confidential may be disclosed publicly by EPA without prior notice.

VII. Public Record and Electronic Submissions

    EPA has established a record for this regulation under docket 
control number [OPP-300905] (including any comments and data submitted 
electronically). A public version of this record, including printed, 
paper versions of electronic comments, which does not include any 
information claimed as CBI, is available for inspection from 8:30 a.m. 
to 4 p.m., Monday through Friday, excluding legal holidays. The public 
record is located in Rm. 119 of the Public Information and Records 
Integrity Branch, Information Resources and Services Division (7502C), 
Office of Pesticide Programs, Environmental Protection Agency, CM #2, 
1921 Jefferson Davis Hwy., Arlington, VA.
    Objections and hearing requests may be sent by e-mail directly to 
EPA at:
     opp-docket@epa.gov


    E-mailed objections and hearing requests must be submitted as an 
ASCII file avoiding the use of special characters and any form of 
encryption.
     The official record for this regulation, as well as the public 
version, as described in this unit will be kept in paper form. 
Accordingly, EPA will transfer any copies of objections and hearing 
requests received electronically into printed, paper form as they are 
received and will place the paper copies in the official record which 
will also include all comments submitted directly in writing. The 
official record is the paper record maintained at the Virginia address 
in ``ADDRESSES'' at the beginning of this document.

VIII. Regulatory Assessment Requirements

A. Certain Acts and Executive Orders

    This final rule establishes a tolerance under section 408 of the 
FFDCA. 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 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 in accordance with Executive Order 13045, entitled Protection of 
Children from Environmental Health Risks and Safety Risks (62 FR 19885, 
April 23, 1997).
    In addition, since tolerances and exemptions that are established 
on the basis of a petition under FFDCA section 408(l)(6), 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. Nevertheless, the Agency previously 
assessed whether establishing tolerances, exemptions from tolerances, 
raising tolerance levels or expanding exemptions might adversely impact 
small entities and concluded, as a generic matter, that there is no 
adverse economic impact. The factual basis for the Agency's generic 
certification for tolerance actions published on May 4, 1981 (46 FR 
24950), and was provided to the Chief Counsel for Advocacy of the Small 
Business Administration.

B. Executive Order 12875

    Under Executive Order 12875, entitled Enhancing the 
Intergovernmental Partnership (58 FR 58093, October 28, 1993), EPA may 
not issue a regulation that is not required by statute and that creates 
a mandate upon a State, local or tribal government, unless the Federal 
government provides the funds necessary to pay the direct compliance 
costs incurred by those governments. If the mandate is unfunded, EPA 
must provide to OMB a description of the extent of EPA's prior 
consultation with representatives of

[[Page 46298]]

affected State, local, and tribal governments, the nature of their 
concerns, copies of any written communications from the governments, 
and a statement supporting the need to issue the regulation. In 
addition, Executive Order 12875 requires EPA to develop an effective 
process permitting elected officials and other representatives of 
State, local, and tribal governments ``to provide meaningful and timely 
input in the development of regulatory proposals containing significant 
unfunded mandates.''
    Today's rule does not create an unfunded Federal mandate on State, 
local, or tribal governments. The rule does not impose any enforceable 
duties on these entities. Accordingly, the requirements of section 1(a) 
of Executive Order 12875 do not apply to this rule.

C. Executive Order 13084

    Under Executive Order 13084, entitled Consultation and Coordination 
with Indian Tribal Governments (63 FR 27655, May 19, 1998), EPA may not 
issue a regulation that is not required by statute, that significantly 
or uniquely affects the communities of Indian tribal governments, and 
that imposes substantial direct compliance costs on those communities, 
unless the Federal government provides the funds necessary to pay the 
direct compliance costs incurred by the tribal governments. If the 
mandate is unfunded, EPA must provide OMB, in a separately identified 
section of the preamble to the rule, a description of the extent of 
EPA's prior consultation with representatives of affected tribal 
governments, a summary of the nature of their concerns, and a statement 
supporting the need to issue the regulation. In addition, Executive 
Order 13084 requires EPA to develop an effective process permitting 
elected officials and other representatives of Indian tribal 
governments ``to provide meaningful and timely input in the development 
of regulatory policies on matters that significantly or uniquely affect 
their communities.''
    Today's rule does not significantly or uniquely affect the 
communities of Indian tribal governments. This action does not involve 
or impose any requirements that affect Indian tribes. Accordingly, the 
requirements of section 3(b) of Executive Order 13084 do not apply to 
this rule.

IX. 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 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 the rule in the Federal Register. This 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 and pests, Reporting and 
recordkeeping requirements.

    Dated: August 11, 1999.

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), 346a and 371.

    2. In Sec. 180.462, by adding paragraph (b) to read as follows:


Sec. 180.462  Pyridate; tolerances for residues.

*    *    *    *    *
    (b) Section 18 emergency exemptions. A time-limited tolerance is 
established for the residue of the herbicide pyridate in connection 
with use of the pesticide under section 18 emergency exemptions granted 
by EPA. This tolerance will expire and is revoked on the date specified 
in the following table:


------------------------------------------------------------------------
                                                          Expiration/
            Commodity              Parts per million    revocation date
------------------------------------------------------------------------
Peppermint, tops (leaves and      0.3 ppm             12/31/01
 stems).
Spearmint, tops (leaves and       0.3 ppm             12/31/01
 stems).
------------------------------------------------------------------------

*    *    *    *    *

[FR Doc. 99-21832 Filed 8-24-99; 8:45 am]
BILLING CODE 6560-50-F
Pyridate; Pesticide Tolerances for Emergency Exemptions

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