[Federal Register Volume 63, Number 91 (Tuesday, May 12, 1998)]
[Rules and Regulations]
[Pages 26082-26089]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-12578]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[OPP-300648; FRL-5787-8]
RIN 2070-AB78


Azoxystrobin; Pesticide Tolerances for Emergency Exemptions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: This regulation establishes a time-limited tolerance for 
combined residues of azoxystrobin or methyl (E)-2-[2-[6-(2-
cyanophenoxy)pyrimidin-4-yloxy]phenyl]-3-methoxyacrylate) and its Z 
isomer in or on cucurbits and watercress . This action is in response 
to EPA's granting of an emergency exemption under section 18 of the 
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) authorizing 
use of the pesticide on cucurbits and watercress in several states. 
This regulation establishes a maximum permissible level for residues of 
azoxystrobin in this food commodity pursuant to section 408(l)(6) of 
the Federal Food, Drug, and Cosmetic Act (FFDCA), as amended by the 
Food Quality Protection Act (FQPA) of 1996.

[[Page 26083]]

The tolerance will expire and is revoked on June 30, 1999.

DATES: This regulation is effective May 12, 1998. Objections and 
requests for hearings must be received by EPA on or before July 13, 
1998.

ADDRESSES: Written objections and hearing requests, identified by the 
docket control number, [OPP-300648], 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-300648], 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, 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: [email protected]. Copies of 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 file 
format or ASCII file format. All copies of objections and hearing 
requests in electronic form must be identified by the docket control 
number [OPP-300648]. No Confidential Business Information (CBI) should 
be submitted through e-mail. Electronic copies of objections and 
hearing requests on this rule may be filed online at many Federal 
Depository Libraries.

FOR FURTHER INFORMATION CONTACT: By mail: Virginia Dietrich, 
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: Crystal Mall #2, 
1921 Jefferson Davis Hwy., Arlington, VA, (703) 308-9359, e-mail: 
[email protected].

SUPPLEMENTARY INFORMATION: EPA, on its own initiative, pursuant to 
section 408(e) and (l)(6) of the FFDCA, 21 U.S.C. 346a(e) and (l)(6), 
is establishing a tolerance for combined residues of the fungicide 
azoxystrobin and its Z isomer, in or on cucurbits and watercress at 1.0 
and 1.0 part per million (ppm). This tolerance will expire and is 
revoked on June 30, 1999. EPA will publish a document in the Federal 
Register to remove the revoked tolerance from the Code of Federal 
Regulations.

I. Background and Statutory Authority

    The FQPA (Pub. L. 104-170) was signed into law August 3, 1996. FQPA 
amends both the FFDCA, 21 U.S.C. 301 et seq., and 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 below 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 tolerance to set binding precedents for the 
application of section 408 and the new safety standard to other 
tolerances and exemptions.

II. Emergency Exemption for Azoxystrobin on Cucurbits and 
Watercress and FFDCA Tolerances

    For watercress, copper hydroxide is the only material registered 
for control of Cercospora leaf spot disease. Several applications of 
copper hydroxide are required per season for adequate control. Although 
copper hydroxide is still effective at controlling Cercospora leaf spot 
disease, due to the many required applications, levels of copper in 
soil and watercress plants have reached phytotoxic levels. As a 
consequence, in areas where watercress has been grown for several 
years, yield has been significantly reduced.
    For cucurbits, azoxystrobin has been requested for the control of 
gummy stem blight and powdery mildew because unusually wet and cloudy 
weather conditions favor disease development. Similar weather 
conditions in 1997 resulted in estimated production losses of 68.4 and 
36.2% in cantaloupe and honeydews. Registered alternatives are 
ineffective due to a combination of weather and resistance factors.
    EPA has authorized under FIFRA section 18 the use of azoxystrobin 
on cucurbits and watercress for control of gummy stem blight on 
cucurbits and Cercospora leaf spot disease in watercress in several 
States. 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 azoxystrobin in or on 
cucurbits and watercress. In doing so, EPA considered the new 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 
new 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

[[Page 26084]]

provided in section 408(l)(6). Although this tolerance will expire and 
is revoked on June 30, 1999, under FFDCA section 408(l)(5), residues of 
the pesticide not in excess of the amounts specified in the tolerance 
remaining in or on cucurbits and watercress 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 this tolerance earlier if any experience with, scientific 
data on, or other relevant information on this pesticide indicate that 
the residues are not safe.
    Because this tolerance is being approved under emergency conditions 
EPA has not made any decisions about whether azoxystrobin meets EPA's 
registration requirements for use on cucurbits and watercress or 
whether a permanent tolerance for this use would be appropriate. Under 
these circumstances, EPA does not believe that this tolerance serves as 
a basis for registration of azoxystrobin 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 the approved States to use this 
pesticide on this crop under section 18 of FIFRA without following all 
provisions of section 18 as identified in 40 CFR part 166. For 
additional information regarding the emergency exemption for 
azoxystrobin, contact the Agency's Registration Division at the address 
provided above.

III. Risk Assessment and Statutory Findings

    EPA performs a number of analyses to determine the risks from 
aggregate exposure to pesticide residues. First, EPA determines the 
toxicity of pesticides based primarily on toxicological studies using 
laboratory animals. These studies address many adverse health effects, 
including (but not limited to) reproductive effects, developmental 
toxicity, toxicity to the nervous system, and carcinogenicity. Second, 
EPA examines exposure to the pesticide through the diet (e.g., food and 
drinking water) and through exposures that occur as a result of 
pesticide use in residential settings.

A. Toxicity

    1. Threshold and non-threshold effects. For many animal studies, a 
dose response relationship can be determined, which provides a dose 
that causes adverse effects (threshold effects) and doses causing no 
observed effects (the ``no-observed effect level'' or ``NOEL'').
    Once a study has been evaluated and the observed effects have been 
determined to be threshold effects, EPA generally divides the NOEL from 
the study with the lowest NOEL by an uncertainty factor (usually 100 or 
more) to determine the Reference Dose (RfD). The RfD is a level at or 
below which daily aggregate exposure over a lifetime will not pose 
appreciable risks to human health. An uncertainty factor (sometimes 
called a ``safety factor'') of 100 is commonly used since it is assumed 
that people may be up to 10 times more sensitive to pesticides than the 
test animals, and that one person or subgroup of the population (such 
as infants and children) could be up to 10 times more sensitive to a 
pesticide than another. In addition, EPA assesses the potential risks 
to infants and children based on the weight of the evidence of the 
toxicology studies and determines whether an additional uncertainty 
factor is warranted. Thus, an aggregate daily exposure to a pesticide 
residue at or below the RfD (expressed as 100% or less of the RfD) is 
generally considered acceptable by EPA. EPA generally uses the RfD to 
evaluate the chronic risks posed by pesticide exposure. For shorter 
term risks, EPA calculates a margin of exposure (MOE) by dividing the 
estimated human exposure into the NOEL from the appropriate animal 
study. Commonly, EPA finds MOEs lower than 100 to be unacceptable. This 
100-fold MOE is based on the same rationale as the 100-fold uncertainty 
factor.
    Lifetime feeding studies in two species of laboratory animals are 
conducted to screen pesticides for cancer effects. When evidence of 
increased cancer is noted in these studies, the Agency conducts a 
weight of the evidence review of all relevant toxicological data 
including short-term and mutagenicity studies and structure activity 
relationship. Once a pesticide has been classified as a potential human 
carcinogen, different types of risk assessments (e.g., linear low dose 
extrapolations or MOE calculation based on the appropriate NOEL) will 
be carried out based on the nature of the carcinogenic response and the 
Agency's knowledge of its mode of action.
    2. Differences in toxic effect due to exposure duration. The 
toxicological effects of a pesticide can vary with different exposure 
durations. EPA considers the entire toxicity data base, and based on 
the effects seen for different durations and routes of exposure, 
determines which risk assessments should be done to assure that the 
public is adequately protected from any pesticide exposure scenario. 
Both short and long durations of exposure are always considered. 
Typically, risk assessments include ``acute,'' ``short-term,'' 
``intermediate term,'' and ``chronic'' risks. These assessments are 
defined by the Agency as follows.
    Acute risk, by the Agency's definition, results from 1-day 
consumption of food and water, and reflects toxicity which could be 
expressed following a single oral exposure to the pesticide residues. 
High end exposure to food and water residues are typically assumed.
    Short-term risk results from exposure to the pesticide for a period 
of 1-7 days, and therefore overlaps with the acute risk assessment. 
Historically, this risk assessment was intended to address primarily 
dermal and inhalation exposure which could result, for example, from 
residential pesticide applications. However, since enaction of FQPA, 
this assessment has been expanded to include both dietary and non-
dietary sources of exposure, and will typically consider exposure from 
food, water, and residential uses when reliable data are available. In 
this assessment, risks from average food and water exposure, and high-
end residential exposure, are aggregated. High-end exposures from all 
three sources are not typically added because of the very low 
probability of this occurring in most cases, and because the other 
conservative assumptions built into the assessment assure adequate 
protection of public health. However, for cases in which high-end 
exposure can reasonably be expected from multiple sources (e.g. 
frequent and widespread homeowner use in a specific geographical area), 
multiple high-end risks will be aggregated and presented as part of the 
comprehensive risk assessment/characterization. Since the toxicological 
endpoint considered in this assessment reflects exposure over a period 
of at least 7 days, an additional degree of conservatism is built into 
the assessment; i.e., the risk assessment nominally covers 1-7 days 
exposure, and the toxicological endpoint/NOEL is selected to be 
adequate for at least 7 days of exposure. (Toxicity results at lower 
levels when the dosing duration is increased.)
    Intermediate-term risk results from exposure for 7 days to several 
months. This assessment is handled in a manner similar to the short-
term risk assessment.
    Chronic risk assessment describes risk which could result from 
several months to a lifetime of exposure. For this assessment, risks 
are aggregated

[[Page 26085]]

considering average exposure from all sources for representative 
population subgroups including infants and children.

B. Aggregate Exposure

    In examining aggregate exposure, FFDCA section 408 requires that 
EPA take into account available and reliable information concerning 
exposure from the pesticide residue in the food in question, residues 
in other foods for which there are tolerances, residues in groundwater 
or surface water that is consumed as drinking water, and other non-
occupational exposures through pesticide use in gardens, lawns, or 
buildings (residential and other indoor uses). Dietary exposure to 
residues of a pesticide in a food commodity are estimated by 
multiplying the average daily consumption of the food forms of that 
commodity by the tolerance level or the anticipated pesticide residue 
level. The Theoretical Maximum Residue Contribution (TMRC) is an 
estimate of the level of residues consumed daily if each food item 
contained pesticide residues equal to the tolerance. In evaluating food 
exposures, EPA takes into account varying consumption patterns of major 
identifiable subgroups of consumers, including infants and children. 
The TMRC is a ``worst case'' estimate since it is based on the 
assumptions that food contains pesticide residues at the tolerance 
level and that 100% of the crop is treated by pesticides that have 
established tolerances. If the TMRC exceeds the RfD or poses a lifetime 
cancer risk that is greater than approximately one in a million, EPA 
attempts to derive a more accurate exposure estimate for the pesticide 
by evaluating additional types of information (anticipated residue data 
and/or percent of crop treated data) which show, generally, that 
pesticide residues in most foods when they are eaten are well below 
established tolerances.
    Percent of crop treated estimates are derived from federal and 
private market survey data. Typically, a range of estimates are 
supplied and the upper end of this range is assumed for the exposure 
assessment. By using this upper end estimate of percent of crop 
treated, the Agency is reasonably certain that exposure is not 
understated for any significant subpopulation group. Further, regional 
consumption information is taken into account through EPA's computer-
based model for evaluating the exposure of significant subpopulations 
including several regional groups, to pesticide residues. For this 
pesticide, the most highly exposed population subgroup (nonursing 
infants (<1 year old)) was not regionally based.

IV. 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 
azoxystrobin and to make a determination on aggregate exposure, 
consistent with section 408(b)(2), for a time-limited tolerance for 
combined residues of azoxystrobin and its Z isomer) on cucurbits and 
watercress at 1.0 and 1.0 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 and The Agency's selection of 
toxicological endpoints upon which to assess risk caused by 
azoxystrobin are discussed below.
    1. Acute toxicity. The Agency evaluated the existing toxicology 
database for azoxystrobin and did not identify an acute dietary 
endpoint. Therefore, a risk assessment is not required.
    2. Short - and intermediate - term toxicity. The Agency evaluated 
the existing toxicology database for short- and intermediate-term 
dermal and inhalation exposure and determined that this risk assessment 
is not required. [Note: From a 21-day dermal toxicity study the NOEL 
was 1,000 mg/kg/day at the highest dose tested (Acute inhalation 
toxicity category III).
    3. Chronic toxicity. EPA has established the RfD for azoxystrobin 
at 0.18 milligrams/kilogram/day (mg/kg/day). This RfD is based on a 
chronic toxicity study in rats with a NOEL of 18.2 mg/kg/day. Reduced 
body weights and bile duct lesions were observed at the lowest-effect-
level (LEL) of 34 mg/kg/day. An Uncertainty Factor (UF) of 100 was used 
to account for both the interspecies extrapolation and the intraspecies 
variability.
    4. Carcinogenicity. The HED RfD/Peer Review Committee (November 7, 
1996) determined that azoxystrobin should be classified as ``Not 
Likely'' to be a human carcinogen according to the proposed revised 
Cancer Guidelines. This classification is based on the lack of evidence 
of carcinogenicity in long-term rat and mouse feeding studies.

B. Exposures and Risks

    1. From food and feed uses. Permanent tolerances have been 
established (40 CFR 180.507(a)) for the combined residues of 
azoxystrobin and its Z isomer, in or on a variety of raw agricultural 
commodities at levels ranging from 0.01 ppm in pecans to 1.0 ppm in 
grapes. In addition, time-limited tolerances have been established (40 
CFR 180.507(b) at levels ranging from 0.006 ppm in milk to 20 ppm in 
rice hulls) in conjunction with previous Section 18 requests. Risk 
assessments were conducted by EPA to assess dietary exposures and risks 
from azoxystrobin 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 one day or single exposure. The Agency did not conduct an acute 
risk assessment because no toxicological endpoint of concern was 
identified during review of available data.
    ii. Chronic exposure and risk. In conducting this chronic dietary 
risk assessment, HED has made very conservative assumptions -- 100% of 
cucurbits, watercress and all other commodities having azoxystrobin 
tolerances will contain azoxystrobin residues and those residues would 
be at the level of the tolerance -- which result in an overestimation 
of human dietary exposure. Thus, in making a safety determination for 
this tolerance, HED is taking into account this conservative exposure 
assessment.
    The existing azoxystrobin tolerances (published, pending, and 
including the necessary Section 18 tolerance(s)) result in a 
Theoretical Maximum Residue Contribution (TMRC) that is equivalent to 
the following percentages of the RfD:

------------------------------------------------------------------------
       Population Sub-Group          TMRC (mg/kg/day)        % RFD      
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U.S. Population (48 States)                     0.002                 1%

[[Page 26086]]

                                                                        
Nursing Infants (<1 year old)                   0.004                 2%
Non-Nursing Infants (<1 year old)               0.009                 5%
Children (1-6 years old)                        0.005                 3%
Children (7-12 years old)                       0.003                 2%
Hispanics                                       0.003                 2%
Non-Hispanics Others                            0.005                 3%
U.S. Population (summer season)                 0.003                 2%
Females (13-19, not preg or                                             
 nursing)                                       0.002                 1%
------------------------------------------------------------------------

    The subgroups listed above are: (a) the U.S. population (48 
states); (b) those for infants and children; (c) females (13-19 years 
old, not pregnant or nursing); and, (d) the other subgroups for which 
the percentage of the RfD occupied is greater than that occupied by the 
subgroup U.S. population (48 states).
    2. From drinking water. There is no established Maximum Contaminant 
Level for residues of azoxystrobin in drinking water. No health 
advisory levels for azoxystrobin in drinking water have been 
established.
    i. Acute exposure and risk. An assessment was not appropriate since 
no toxicological endpoint of concern was identified during review of 
the available data.
    ii. Chronic exposure and risk. Based on the chronic dietary (food) 
exposure estimates, chronic drinking water levels of concern (DWLOC) 
for azoxystrobin were calculated and are summarized in Table 1. 
Estimated environmental concentrations (EECs) using GENEEC for 
azoxystrobin on bananas, grapes, peaches, peanuts, pecans, tomatoes, 
and wheat are listed in SWAT Team Second Interim Report (6/20/97). The 
highest EEC for azoxystrobin in surface water is from the application 
of azoxystrobin on grapes (39 g/L) and is substantially lower 
than the DWLOCs calculated. Therefore, chronic exposure to azoxystrobin 
residues in drinking water do not exceed the Agency's level of concern.

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                                                        Table 1. Drinking Water Levels of Concern                                                       
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                                                                                 TMRC [Food Exposure]    Max Water Exposure\1\   DWLOC 2,3,4 (g/
                                                          RfD (mg/kg/day)            (mg/kg/day)              (mg/kg/day)                   L)          
--------------------------------------------------------------------------------------------------------------------------------------------------------
U.S. Population (48 States).........................                     0.18                  0.00231                    0.178                     6200
Females (13+ years old, not pregnant or nursing)....                     0.18                  0.00176                    0.178                     5300
Non-nursing Infants (< 1 year old)..................                     0.18                  0.00879                    0.171                    1700 
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Maximum Water Exposure (mg/kg/day) = RfD (mg/kg/day) - TMRC from DRES (mg/kg/day)                                                                   
\2\ DWLOC(g/L) = Max water exposure (mg/kg/day) * body wt (kg) /[(10-3 mg/g)*water consumed daily (L/day)]                            
\3\ HED Default body wts for males, females, and children are 70 kg, 60 kg, and 10 kg respectively.                                                     
\4\ HED Default Daily Drinking Rates are 2 L/Day for Adults and 1 L/Day for children                                                                    

    3. From non-dietary exposure. Azoxystrobin is not currently 
registered for use on residential non-food sites.
    4. Cumulative exposure to substances with common mechanism of 
toxicity. Azoxystrobin is related to the naturally occurring 
strobilurins. There are no other members of this class of fungicides 
registered with the Agency. 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.'' The Agency believes that 
``available information'' in this context might include not only 
toxicity, chemistry, and exposure data, but also scientific policies 
and methodologies for understanding common mechanisms of toxicity and 
conducting cumulative risk assessments. For most pesticides, although 
the Agency has some information in its files that may turn out to be 
helpful in eventually determining whether a pesticide shares a common 
mechanism of toxicity with any other substances, EPA does not at this 
time have the methodologies to resolve the complex scientific issues 
concerning common mechanism of toxicity in a meaningful way. EPA has 
begun a pilot process to study this issue further through the 
examination of particular classes of pesticides. The Agency hopes that 
the results of this pilot process will increase the Agency's scientific 
understanding of this question such that EPA will be able to develop 
and apply scientific principles for better determining which chemicals 
have a common mechanism of toxicity and evaluating the cumulative 
effects of such chemicals. The Agency anticipates, however, that even 
as its understanding of the science of common mechanisms increases, 
decisions on specific classes of chemicals will be heavily dependent on 
chemical specific data, much of which may not be presently available.
    Although at present the Agency does not know how to apply the 
information in its files concerning common mechanism issues to most 
risk assessments, there are pesticides as to which the common mechanism 
issues can be resolved. These pesticides include pesticides that are 
toxicologically dissimilar to existing chemical substances (in which 
case the Agency can conclude that it is unlikely that a pesticide 
shares a common mechanism of activity with other substances) and 
pesticides that produce a common toxic metabolite (in which case common 
mechanism of activity will be assumed).
    EPA does not have, at this time, available data to determine 
whether azoxystrobin 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, 
azoxystrobin 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 azoxystrobin has a

[[Page 26087]]

common mechanism of toxicity with other substances.

C. Aggregate Risks and Determination of Safety for U.S. Population

    1. Chronic risk. Using the conservative TMRC exposure assumptions 
described above, and taking into account the completeness and 
reliability of the toxicity data, HED has estimated the exposure to 
azoxystrobin from food will utilize 1% of the RfD for the U.S. 
population. HED generally has no concern for exposures below 100% of 
the RfD because the RfD 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 
azoxystrobin in drinking water, HED does not expect the aggregate 
exposure to exceed 100% of the RfD. Under current HED guidelines, the 
registered non-dietary uses of azoxystrobin do not constitute a chronic 
exposure scenario. HED concludes that there is a reasonable certainty 
that no harm will result from chronic aggregate exposure to 
azoxystrobin residues. EPA concludes that there is a reasonable 
certainty that no harm will result from aggregate exposure to 
azoxystrobin residues.
    2. 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 indoor and outdoor 
residential exposure. This risk assessment is not applicable since no 
indoor and outdoor residential exposure uses are currently registered 
for azoxystrobin.

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

    1. Safety factor for infants and children-- In general. In 
assessing the potential for additional sensitivity of infants and 
children to residues of azoxystrobin, 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 pre-and post-natal toxicity and the 
completeness of the database 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 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 inter- and intra-
species 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.
    2. Developmental toxicity studies--i.  Rabbit. In the developmental 
toxicity study in rabbits, developmental NOEL was 500 mg/kg/day, at the 
highest dose tested (HDT). Because there were no treatment-related 
effects, the developmental LEL was >500 mg/kg/day. The maternal NOEL 
was 150 mg/kg/day. The maternal LEL of 500 mg/kg/day was based on 
decreased body weight gain during dosing.
    ii. Rat. In the developmental toxicity study in rats, the maternal 
(systemic) NOEL was not established. The maternal LEL of 25 mg/kg/day 
at the lowest dose tested (LDT) was based on increased salivation. The 
developmental (fetal) NOEL was 100 mg/kg/day (HDT).
    3. Reproductive toxicity study-- i. Rat. In the reproductive 
toxicity study (MRID #43678144) in rats, the parental (systemic) NOEL 
was 32.3 mg/kg/day. The parental LEL of 165.4 mg/kg/day was based on 
decreased body weights in males and females, decreased food consumption 
and increased adjusted liver weights in females, and cholangitis. The 
reproductive NOEL was 32.3 mg/kg/day. The reproductive LEL of 165.4 mg/
kg/day was based on increased weanling liver weights and decreased body 
weights for pups of both generations.
    ii. Pre- and post-natal sensitivity. The pre- and post-natal 
toxicology data base for azoxystrobin is complete with respect to 
current toxicological data requirements. The results of these studies 
indicate that infants and children are not more sensitive to exposure, 
based on the results of the rat and rabbit developmental toxicity 
studies and the 2-generation reproductive toxicity study in rats. The 
additional 10X safety factor to account for sensitivity of infants and 
children was removed by an ad hoc FQPA Safety Factor Committee.
    iii. Conclusion. The results of these studies indicate that infants 
and children are not more sensitive to exposure, based on the results 
of the rat and rabbit developmental toxicity studies and the 2-
generation reproductive toxicity study in rats. The additional 10X 
safety factor to account for sensitivity of infants and children was 
removed by an ad hoc FQPA Safety Factor Committee.
    4. Chronic risk. Using the conservative exposure assumptions 
described above, EPA has concluded that aggregate exposure to 
azoxystrobin from food will utilize 2 to 5% of the RfD for infants and 
children. EPA generally has no concern for exposures below 100% of the 
RfD because the RfD 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 
azoxystrobin in drinking water and from non-dietary, non-occupational 
exposure, EPA does not expect the aggregate exposure to exceed 100% of 
the RfD. EPA concludes that there is a reasonable certainty that no 
harm will result to infants and children from aggregate exposure to 
azoxystrobin residues.

V. Other Considerations

A. Metabolism In Plants and Animals

    The nature of the residue in grapes is adequately understood. The 
residue of concern in grapes is parent azoxystrobin and its Z isomer. 
The qualitative nature of the residue in wheat is adequately 
understood. Again, the major residues are azoxystrobin and the Z isomer 
in wheat metabolism studies. These data are being translated for 
watercress for this emergency exemption.
    The qualitative nature of the residue in animals is adequately 
understood for the purposes of this Section 18 request. A ruminant 
metabolism study has been submitted, however the animal metabolism data 
have not been reviewed by the Office of Pesticide Program's Metabolism 
Assessment Review Committee. The residues of concern in ruminants 
appears to be different from that of plants. Unidentified metabolite 
compounds, designated metabolites 2, 20, and 28, appear to be the major 
components of the residue in ruminant tissues. For the purposes of 
these time-limited tolerances for emergency exemptions only, the 
residues of concern in animal tissues are azoxystrobin and its Z-
isomer.

[[Page 26088]]

B. Analytical Enforcement Methodology

    A method (SOP RAM 243/03, GLC/NPD) to determine residues of 
azoxystrobin and its Z isomer in banana, peach, peanut, tomato, and 
wheat commodities has been submitted. This method has been 
independently validated as per PR Notice 88-5. An Agency validation of 
this method is pending. The Agency concludes this method is adequate 
for enforcement of the requested Section 18 tolerances on plant 
commodities.
    GLC/NPD method RAM 255/01 is adequate for collection of residue 
data for azoxystrobin in animal commodities. Adequate independent 
method validation and concurrent method recovery data have been 
submitted. Method SOP RAM 255/01 has been submitted for Agency method 
validation. The Agency concludes this method is adequate for 
enforcement of the necessary Section 18 tolerances on livestock 
commodities.

C. Magnitude of Residues

    Residues of azoxystrobin and its Z isomer are not expected to 
exceed 1.0 ppm in/on cucurbits or watercress as a result of this 
Section 18 use. Time-limited tolerances should be established at this 
level.

D. Rotational Crop Restrictions

    Rotational crop data were previously submitted. Based on this 
information, a 45 day plantback interval is appropriate for all crops.

E. International Residue Limits

    There are no CODEX, Canadian, or Mexican Maximum Residue Limits 
(MRL) for azoxystrobin on cucurbits or watercress. Thus, harmonization 
is not an issue for these section 18 requests.

VI. Conclusion

    Therefore, the tolerance is established for combined residues of 
azoxystrobin and its Z isomer in cucurbits and watercress at 1.0 and 
1.0 ppm.

VII. Objections and Hearing Requests

    The new FFDCA section 408(g) provides essentially the same process 
for persons to ``object'' to a tolerance regulation issued by EPA under 
new section 408(e) and (l)(6) 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 July 13, 1998, 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 above (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). 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.

VIII. Public Docket

    EPA has established a record for this rulemaking under docket 
control number [OPP-300648] (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 Room 119 of the Public Information and Records 
Integrity Branch, Information Resources and Services Division (7502C), 
Office of Pesticide Programs, Environmental Protection Agency, Crystal 
Mall #2, 1921 Jefferson Davis Highway, Arlington, VA.
    Electronic comments may be sent directly to EPA at:
    [email protected].


    Electronic comments must be submitted as an ASCII file avoiding the 
use of special characters and any form of encryption.
    The official record for this rulemaking, as well as the public 
version, as described above 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 rulemaking record which 
will also include all comments submitted directly in writing. The 
official rulemaking record is the paper record maintained at the 
Virginia address in ``ADDRESSES'' at the beginning of this document.

IX. 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) (Pub. L. 104-4). Nor does 
it require any prior consultation as specified by Executive Order 
12875, entitled Enhancing the Intergovernmental Partnership (58 FR 
58093, October 28, 1993), or 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 these tolerances and exemptions that are 
established 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

[[Page 26089]]

Flexibility Act (RFA) (5 U.S.C. 601 et seq.) do not apply. 
Nevertheless, the Agency has 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.

X. Submission to Congress and the Comptroller General

    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the 
Small Business Regulatory Enforcement Fairness Act of 1996, 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 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: April 27, 1998.

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. 346a and 371.

    2. Section 180.507 is amended in paragraph (b) by alphabetically 
adding the following commodities to the table to read as follows:


Sec.  180.507   Azoxystrobin; tolerances for residues.

    *  *  *  *  *  
    (b) *  *  *  

                                                                        
------------------------------------------------------------------------
                                                          Expiration/   
            Commodity              Parts per million    Revocation Date 
------------------------------------------------------------------------
                                                                        
*            *            *              *              *              *
                                          *                             
Cucurbits.......................  1.0                 6/30/99           
                                                                        
*            *            *              *              *              *
                                          *                             
Watercress......................  1.0                 6/30/99           
------------------------------------------------------------------------

*    *    *    *    *

[FR Doc. 98-12578 Filed 5-11-98; 8:45 am]
BILLING CODE 6560-50-F