Propiconazole; Notice of Filing a Pesticide Petition to Establish a Tolerance for a Certain Pesticide Chemical in or on Food

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice.

SUMMARY:

This notice announces the filing of a pesticide petition proposing the establishment of regulations to extend the tolerances for residues of a certain pesticide chemical in or on various food commodities.

DATES:

Comments, identified by docket ID number OPP-2004-0053, must be received on or before March 29, 2004.

ADDRESSES:

Comments may be submitted electronically, by mail, or through hand delivery/courier. Follow the detailed instructions as provided in Unit I. of the SUPPLEMENTARY INFORMATION.

FOR FURTHER INFORMATION CONTACT:

Mary L. Waller, Registration Division (7505C), Office of Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; telephone number: (703) 308-9354; e-mail address: waller.mary@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

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

• Crop production (NAICS 111)
• Animal production (NAICS 112)
• Food manufacturing (NAICS 311)
• Pesticide manufacturing (NAICS 32532)

This listing is not intended to be exhaustive, but rather provides a guide for readers regarding entities likely to be affected by this action. Other types of entities not listed in this unit could also be affected. The North American Industrial Classification System (NAICS) codes have been provided to assist you and others in determining whether this action might apply to certain entities. If you have any questions regarding the applicability of this action to a particular entity, consult the person listed under FOR FURTHER INFORMATION CONTACT.

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

1. Docket. EPA has established an official public docket for this action under docket identification (ID) number OPP-2004-0053. The official public docket consists of the documents specifically referenced in this action, any public comments received, and other information related to this action. Although a part of the official docket, the public docket does not include Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. The official public docket is the collection of materials that is available for public viewing at the Public Information and Records Integrity Branch (PIRIB), Rm. 119, Crystal Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA. This docket facility is open from 8:30 a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The docket telephone number is (703) 305-5805.

2. Electronic access. You may access this Federal Register document electronically through the EPA Internet under the “Federal Register” listings at http://www.epa.gov/fedrgstr/.

An electronic version of the public docket is available through EPA's electronic public docket and comment system, EPA Dockets. You may use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public comments, access the index listing of the contents of the official public docket, and to access those documents in the public docket that are available electronically. Although not all docket materials may be available electronically, you may still access any of the publicly available docket materials through the docket facility identified in Unit I.B.1. Once in the system, select “search,” then key in the appropriate docket ID number.

Certain types of information will not be placed in the EPA Dockets. Information claimed as CBI and other information whose disclosure is restricted by statute, which is not included in the official public docket, will not be available for public viewing in EPA's electronic public docket. EPA's policy is that copyrighted material will not be placed in EPA's electronic public docket but will be available only in printed, paper form in the official public docket. To the extent feasible, publicly available docket materials will be made available in EPA's electronic public docket. When a document is selected from the index list in EPA Dockets, the system will identify whether the document is available for viewing in EPA's electronic public docket. Although not all docket materials may be available electronically, you may still access any of the publicly available docket materials through the docket facility identified in Unit I.B. EPA intends to work towards providing electronic access to all of the publicly available docket materials through EPA's electronic public docket.

For public commenters, it is important to note that EPA's policy is that public comments, whether submitted electronically or in paper, will be made available for public viewing in EPA's electronic public docket as EPA receives them and without change, unless the comment contains copyrighted material, CBI, or other information whose disclosure is restricted by statute. When EPA identifies a comment containing copyrighted material, EPA will provide a reference to that material in the version of the comment that is placed in EPA's electronic public docket. The entire printed comment, including the copyrighted material, will be available in the public docket.

Public comments submitted on computer disks that are mailed or delivered to the docket will be transferred to EPA's electronic public docket. Public comments that are mailed or delivered to the docket will be scanned and placed in EPA's electronic public docket. Where practical, physical objects will be photographed, and the photograph will be placed in EPA's electronic public docket along with a brief description written by the docket staff.

C. How and to Whom Do I Submit Comments?

You may submit comments electronically, by mail, or through hand delivery/courier. To ensure proper receipt by EPA, identify the appropriate docket ID number in the subject line on the first page of your comment. Please ensure that your comments are submitted within the specified comment period. Comments received after the close of the comment period will be marked “late.” EPA is not required to consider these late comments. If you wish to submit CBI or information that is otherwise protected by statute, please follow the instructions in Unit I.D. Do not use EPA Dockets or e-mail to submit CBI or information protected by statute.

1. Electronically. If you submit an electronic comment as prescribed in this unit, EPA recommends that you include your name, mailing address, and an e-mail address or other contact information in the body of your comment. Also include this contact information on the outside of any disk or CD-ROM you submit, and in any cover letter accompanying the disk or CD-ROM. This ensures that you can be identified as the submitter of the comment and allows EPA to contact you in case EPA cannot read your comment due to technical difficulties or needs further information on the substance of your comment. EPA's policy is that EPA will not edit your comment, and any identifying or contact information provided in the body of a comment will be included as part of the comment that is placed in the official public docket, and made available in EPA's electronic public docket. If EPA cannot read your comment due to technical difficulties and cannot contact you for clarification, EPA may not be able to consider your comment.

i. EPA Dockets. Your use of EPA's electronic public docket to submit comments to EPA electronically is EPA's preferred method for receiving comments. Go directly to EPA Dockets at http://www.epa.gov/edocket/, and follow the online instructions for submitting comments. Once in the system, select “search,” and then key in docket ID number OPP-2004-0053. The system is an “anonymous access” system, which means EPA will not know your identity, e-mail address, or other contact information unless you provide it in the body of your comment.

ii. E-mail. Comments may be sent by e-mail to opp-docket@epa.gov, Attention: Docket ID Number OPP-2004-0053. In contrast to EPA's electronic public docket, EPA's e-mail system is not an “anonymous access” system. If you send an e-mail comment directly to the docket without going through EPA's electronic public docket, EPA's e-mail system automatically captures your e-mail address. E-mail addresses that are automatically captured by EPA's e-mail system are included as part of the comment that is placed in the official public docket, and made available in EPA's electronic public docket.

iii. Disk or CD-ROM. You may submit comments on a disk or CD-ROM that you mail to the mailing address identified in Unit I.C.2. These electronic submissions will be accepted in WordPerfect or ASCII file format. Avoid the use of special characters and any form of encryption.

2. By mail. Send your comments to: Public Information and Records Integrity Branch (PIRIB) (7502C), Office of Pesticide Programs (OPP), Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001, Attention: Docket ID Number OPP-2004-0053.

3. By hand delivery or courier. Deliver your comments to: Public Information and Records Integrity Branch (PIRIB), Office of Pesticide Programs (OPP), Environmental Protection Agency, Rm. 119, Crystal Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA, Attention: Docket ID Number OPP-2004-0053. Such deliveries are only accepted during the docket's normal hours of operation as identified in Unit I.B.1.

D. How Should I Submit CBI to the Agency?

Do not submit information that you consider to be CBI electronically through EPA's electronic public docket or by e-mail. You may claim information that you submit to EPA as CBI by marking any part or all of that information as CBI (if you submit CBI on disk or CD-ROM, mark the outside of the disk or CD-ROM as CBI and then identify electronically within the disk or CD-ROM the specific information that is CBI). Information so marked will not be disclosed except in accordance with procedures set forth in 40 CFR part 2.

In addition to one complete version of the comment that includes any information claimed as CBI, a copy of the comment that does not contain the information claimed as CBI must be submitted for inclusion in the public docket and EPA's electronic public docket. If you submit the copy that does not contain CBI on disk or CD-ROM, mark the outside of the disk or CD-ROM clearly that it does not contain CBI. Information not marked as CBI will be included in the public docket and EPA's electronic public docket without prior notice. If you have any questions about CBI or the procedures for claiming CBI, please consult the person listed under FOR FURTHER INFORMATION CONTACT.

E. What Should I Consider as I Prepare My Comments for EPA?

You may find the following suggestions helpful for preparing your comments:

1. Explain your views as clearly as possible.

2. Describe any assumptions that you used.

3. Provide copies of any technical information and/or data you used that support your views.

4. If you estimate potential burden or costs, explain how you arrived at the estimate that you provide.

5. Provide specific examples to illustrate your concerns.

6. Make sure to submit your comments by the deadline in this notice.

7. To ensure proper receipt by EPA, be sure to identify the docket ID number assigned to this action in the subject line on the first page of your response. You may also provide the name, date, and Federal Register citation.

II. What Action is the Agency Taking?

EPA has received pesticide petitions as follows proposing the establishment and/or amendment of regulations for residues of a certain pesticide chemical in or on various food commodities under section 408 of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a. EPA has determined that the petitions contain data or information regarding the elements set forth in FFDCA section 408(d)(2); however, EPA has not fully evaluated the sufficiency of the submitted data at this time or whether the data support granting of the petitions. Additional data may be needed before EPA rules on the petitions.

List of Subjects

• Environmental protection
• Agricultural commodities
• Feed additives
• Food additives
• Pesticides and pests
• Reporting and recordkeeping requirements

Summary of Petitions

The petitioner summary of the pesticide petitions is printed below as required by FFDCA section 408(d)(3). The summary of the petitions was prepared by the petitioner and represents the view of the petitioner. The petitions summary announces the availability of a description of the analytical methods available to EPA for the detection and measurement of the pesticide chemical residues or an explanation of why no such method is needed.

Syngenta Crop Protection, Inc.

PP 8F3654 and PP 8F3674

EPA has received pesticide petitions (PP 8F3654 and PP 8F3674) from Syngenta Crop Protection, Inc., P.O. Box 18300, Greensboro, NC 27419-8300 proposing, pursuant to section 408(d) of FFDCA, 21 U.S.C. 346a(d), to amend 40 CFR 180.434 by extending the time-limited tolerances for residues of propiconazole (1-[[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl]-1H-1,2,4-triazole) in or on corn, field, forage at 12 parts per million (ppm); corn, field, grain at 0.1 ppm; corn, field, stover at 12 ppm; corn, sweet, kernel plus cob with husks removed at 0.1 ppm; pineapple at 0.1 ppm; pineapple, fodder at 0.1 ppm (8F3674); peanuts at 0.2 ppm; and peanuts, hay at 20 ppm (8F3654).

A. Residue Chemistry

1. Plant metabolism. The metabolism of propiconazole as well as the nature of the residues is adequately understood for purposes of the tolerances. Plant metabolism has been evaluated in five diverse crops, wheat, grapes, celery, peanuts and carrots which should serve to define the similar metabolism of propiconazole in a wide range of crops. The plant metabolism pathway for propiconazole is well understood. Parent metabolite CGA-64250 is the major compound found in crops. Comparison of the metabolism of propiconazole in different plant species shows that the differences between the respective metabolic pathways to be quantitative in nature.

2. Analytical method. The metabolism data in plants and animals suggest that analytical methods to detect either the phenyl or the triazole ring would be appropriate for the measurement of residues. However, because of the natural occurrence of compounds that interfere with the measurement of triazoles, methods designed to detect this moiety have been proven unreliable and unacceptable. Conversely, conversion of phenyl moiety to 2,4-dichlorobenzoic acid (DCBA) has proven to be satisfactory for all agricultural products analyzed to date. Analytical method AG-454A was developed for the determination of residues of propiconazole and its metabolites containing the DCBA moiety. This method has been accepted and published by EPA as the tolerance enforcement method for crops. The limit of quantitation (LOQ) for the method is 0.05 ppm.

3. Magnitude of residues. Field residue trials have been conducted at various rates, timing intervals, and applications methods to represent the use patterns which would most likely result in the highest residues. For all samples, the total residue method was used for determination of the combined residues of parent and its metabolites which contain the DCBA moiety.

B. Toxicological Profile

1. Acute toxicity. Propiconazole exhibits low toxicity. Data indicated the following: A rat acute oral lethal dose (LD)₅₀ of 1,517 milligrams/kilogram (mg/kg); a rabbit acute dermal LD₅₀>6,000 mg/kg; a rat inhalation lethal concentration (LC)₅₀>5.8 mg/liter air; minimal skin and slight eye irritation; and nonsensitization.

2. Genotoxicty. Propiconazole exhibits no mutagenic potential based on the following data: In vitro gene mutation test (Ames assay, rat hepatocyte DNA repair test, (human fibroblast DNA repair test); in vitro chromosome test, (human lymphocyte cytogenetic test); in vivo mutagenicity test, (Chinese hamster bone marrow cell nucleus anomaly test, Chinese hamster bone marrow cell micronucleus test, mouse dominant lethal test); and other mutagenicity test (BALB/3T3 cell transformation assay).

3. Reproductive and developmental toxicity. In an oral teratology study in the rabbit, a maternal no observed adverse effect level (NOAEL) of 30 mg/kg was based on reduced food intake but without any fetotoxicity even at the top dose of 180 mg/kg. In an oral teratology study in the rabbit, a maternal NOAEL of 100 mg/kg was based on reductions in body weight gain and food consumption and a fetal NOAEL of 250 mg/kg was based on increased skeletal variations at 400 mg/kg. In an oral teratology study in the rat, a maternal and fetal NOAEL of 100 mg/kg was based on decreased survival, body weight gain, and food consumption in the dams and delayed ossification in the fetuses at 300 mg/kg. In a second teratology study in the rat, a maternal and fetal NOAEL of 30 mg/kg was based on reductions in body weight gain and food consumption in the dams and delayed development in the fetuses at 90 and 360/300 mg/kg. A supplemental teratology study in the rat involving eight times as many animals per group as usually required showed no teratogenic potential for the compound. A 2-generation reproduction study in the rat showed excessive toxicity at 5,000 ppm without any teratogenic effects. A 2-generation reproduction study in the rat showed no effects on reproductive or fetal parameters at any dose level. Postnatal growth and survival were affected at the top dose of 2,500 ppm, and parental toxicity was also evident. The NOAEL for development toxicity is 500 ppm.

4. Subchronic toxicity. In a 21-day dermal study in the rabbit, a NOAEL of 200 mg/kg was based on clinical signs of systemic toxicity. In a 28-day oral toxicity study in the rat, a NOAEL of 50 mg/kg was based on increased liver weight. In a subchronic feeding study in the mouse, a NOAEL of 20 ppm (3 mg/kg) was based on liver pathologic changes. In a 13-week feeding study in the male mouse, a NOAEL of 20 ppm (3 mg/kg) was based on liver pathologic changes. In a 90-day feeding study in rats, the NOAEL was 240 ppm (24 mg/kg) based on a reduction in body weight gain. In a 90-day feeding study in dogs, the NOAEL was 250 ppm (6.25 mg/kg) based on reduced food intake and stomach histologic changes.

5. Chronic feeding toxicity and carcinogenicity. In a 12-month feeding study in the dog, a NOAEL of 50 ppm (1.25 mg/kg) was based on stomach histologic changes. In a 24-month oncogenicity feeding study in the mouse, the NOAEL was 100 ppm (15 mg/kg). The maximum tolerated dose (MTD) was exceeded at 2,500 ppm in males based on decreased survival and body weight. Increased incidence of liver tumor was seen in these males but no evidence of carcinogenicity was seen at the next lower dose of 500 ppm in either sex. In a 24-month chronic feeding/oncogenicity study in the rat, a NOAEL of 100 ppm (5 mg/kg) was based on body weight and blood chemistry. The MTD was 2,500 ppm based on reduction in body weight gain and no evidence of oncogenicity was seen. Based on the available chronic toxicity data, Syngenta believes the reference dose (RfD) for propiconazole is 0.0125 mg/kg/day. This RfD is based on a 1 year feeding study in dogs with a NOAEL of 1.25 mg/kg/day (50 ppm) and an uncertainly factor of 100. No additional modifying factor for the nature of effects was judged to be necessary as stomach mucous hyperemia was the most sensitive indicator of toxicity in that study.

Using the “Guidelines for Carcinogenic Risk Assessment” published on September 24, 1986 (51 FR 33992), EPA has classified propiconazole in Group C for carcinogenicity (evidence of possible carcinogenicity for humans). The compound was tested in 24-month studies with both rats and mice. The only evidence of carcinogenicity was an increase in liver tumor incidence in male mice at a dose level that exceeded the MTD. Dosage levels in the rat study were appropriate for identifying a cancer risk. The Cancer Peer Review Committee recommended the RfD approach for quantitation of human risk. Therefore, the RfD is deemed protective of all chronic human health effects, including cancer.

6. Animal metabolism. Metabolism in animals is similar to plant metabolism. In animals both the rat and the goat rapidly metabolize and excrete propiconazole. Neither animal retains significant amounts of propiconazole or its metabolites in tissues. Significant quantities of parent or metabolites do not appear in goat's milk. Similar metabolites are produced by both species, and unconjugated (Phase I) metabolites are similar in plants and animals.

The metabolism profile supports the use of an analytical enforcement method that accounts for combined residues of propiconazole and its metabolites that contain the DCBA moiety.

7. Metabolite toxicology. There are no metabolites of concern based on a differential metabolism between plants and animals.

8. Endocrine disruption. Developmental toxicity studies in rats and rabbits and reproduction studies in rats gave no indication that propiconazole might have any effects on endocrine function related to development and reproduction. The subchronic and chronic studies also showed no evidence of a long-term effect related to the endocrine system. Further, due to the moderate rate of degradation of the product, there is no risk that propiconazole may accumulate in the environment. In animals, propiconazole is quickly excreted and has no tendency for accumulation in the body. Based on these results, it is very likely that propiconazole has no potential to interfere specifically with the endocrine system.

C. Aggregate Exposure

1. Dietary exposure. Tier III/IV acute and chronic dietary exposure evaluations were completed using the Dietary Exposure Evaluation Model (DEEM^TM), version 7.87 from Exponent. All consumption data for these assessments was taken from the U.S. Department of Agriculture's Continuing Survey of Food Intake by Individuals (CSFII) with the 1994-1996 consumption data base and the Supplemental CSFII Children's Survey (1998) consumption data base. These exposure assessments included all registered crop uses (almonds, apricots, bananas, barley, blueberries, celery, cherries, corn (field), corn (sweet), cranberries, dry beans and peas, filberts (hazelnuts), grasses grown for seed, nectarines, oats, peaches, peanuts, pecans, peppermint, pineapples, plums, prunes, raspberries, rice, rye, spearmint, sorghum, sugar cane, wheat and wild rice). Empirically derived processing studies for peanut oil (0.37X), sorghum aspirated grain fractions (5.21X), spearmint oil (0.66X), and sorghum flour (0.23X) were used in these assessments. All other processing factors used DEEM^TM defaults. Secondary residues in animal commodities were estimated based on theoretical worst-case, yet nutritionally adequate animal diets and residue transfer factors calculated from feeding studies.

a. Food. For the purposes of assessing the potential dietary exposures under the current tolerances, Syngenta estimated aggregate exposures from all crops for which tolerances are established. These assessments utilized residue data from field trials where propiconazole was applied at the maximum intended use rate and samples were harvested at the minimum pre-harvest interval (PHI) to obtain maximum residues. In these Tier III/IV dietary exposure assessments, Syngenta Market Basket Survey residue data was used for the following commodities: Bananas, celery, sweet corn, cherries, peaches, peanut butter and wheat flour. Percent of crop treated (%CT) values were based on Doane's 2001 data base. Since percent crop treated is inherent in the market basket data, no percent crop treated correction was used for commodities analyzed in the Syngenta Market Basket Survey.

i. Acute exposure. An acute reference dose of 0.30 mg/kg bwt/day for the females 13-50 years subpopulation only was based on a NOAEL of 30 mg/kg bwt/day from a rat developmental toxicity study and an uncertainly factor of 100X. The 100-fold safety factor includes intraspecies and interspecies variations. No additional FQPA safety factor was applied. Acute exposure to the females 13-50 years subpopulation was expressed as a percent of the acute RfD. Acute dietary exposure to females 13-50 years old at the 99.9th percentile of exposures was negligible (0.3% of the acute RfD of 0.30 mg/kg body weight/day). Since EPA generally has no concern for exposures below 100% of the RfD, Syngenta believes that there is a reasonable certainty that no harm will result from dietary (food) exposure to residues arising from the current uses of propiconazole.

ii. Chronic exposure. The chronic reference dose (RfD) of propiconazole is 0.0125 mg/kg bwt/day and is based on a chronic dog feeding study with a NOAEL of 1.25 mg/kg bwt/day and an uncertainly factor of 100X. The 100-fold safety factor includes intraspecies and interspecies variations. No additional FQPA safety factor was applied. Exposures were expressed as a percent of the chronic RfD. Chronic exposure to the most exposed subpopulation (children 1 and 2 years old) was 0.5% of the chronic RfD of 0.0125 mg/kg bwt/day. Since EPA generally has no concern for exposures below 100% of the RfD, Syngenta believes that there is a reasonable certainty that no harm will result from dietary (food) exposure to residues arising from the current uses of propiconazole.

b. Drinking water. EPA uses the Pesticide Root Zone/Exposure Analysis Modeling System (PRZM/EXAMS) to estimate pesticide concentrations in surface water and Screening Concentration in Ground Water (SCI-GROW) to predict pesticide concentrations in ground water. None of these models include consideration of the impact processing of raw water (mixing, dilution, or treatment) 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 conservative approximation of the estimated environmental concentration (EEC) of specific pesticides in drinking water. The highest use rate for propiconazole is on turf; therefore, this use was evaluated to assess the potential environmental exposure to drinking water. For ground water (SCI-GROW) modeling, Syngenta has determined that EECs of propiconazole at the highest use rate (1.77 pound/active ingredient/acre x 4 applications, turf use) are 1.48 parts per billion (ppb) for both acute and chronic exposure. Using the same propiconazole use rate for surface water (PRZM/EXAMS) modeling, acute and chronic EECs were 4.69 ppb and 2.99 ppb, respectively. EECs of propiconazole are compared to the acute and chronic Drinking Water Levels of Comparison (DWLOC). Since the surface water EECs exceed the ground water EECs, the surface water values will be used for comparison purposes and will be considered protective for any ground water concentration concerns.

i. Chronic risk. DWLOCs were calculated based on a chronic Population Adjusted Dose (PAD) of 0.013 mg/kg/day. Chronic drinking water exposure represents 2.3% of the chronic PAD for a 10 kg child consuming 1 L water/day. The children 1 to 2 years subpopulation generated the lowest chronic DWLOC of 129 ppb. Since the chronic DWLOC of 129 ppb is considerably higher than the chronic EEC of 2.99 ppb, EPA should not have a concern for chronic risk to either surface water or ground water.

ii. Acute risk. The acute DWLOC was calculated based on an acute PAD of 0.30 mg/kg/day. Acute drinking water exposure represents 0.05% of the acute PAD for a 60 kg female consuming 2 L water/day. The females 13 years and older subpopulation is the only subgroup of concern and generated an acute DWLOC of 8,972 ppb. Since the acute DWLOC of 8,972 ppb is considerably higher than the acute EEC of 4.69 ppb, EPA should not have a concern for acute risk to either surface water or ground water.

2. Non-dietary exposure. Propiconazole is registered for residential use as a preservative treatment for wood and for lawn and ornamental uses. At this time, no reliable data exist which would allow quantitative incorporation of risk from these uses into a human health risk assessment. The exposure to propiconazole from contacting treated wood products is anticipated to be very low since the surface of wood is usually coated with paint or sealant when used in or around the house. The non-occupational exposure from lawn and ornamental applications is also considered to be minor. It is estimated that less than 0.01% of all households nationally use propiconazole in a residential setting.

3. Aggregate exposure. Based on the completeness and reliability of the toxicity data supporting these petitions, Syngenta believes that there is a reasonable certainty that no harm will result from aggregate exposure to residues arising from current propiconazole uses, including anticipated dietary exposure from food, water, and all other types of non-occupational exposures.

D. Cumulative Effects

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 propiconazole has a common mechanism of toxicity with other substances or how to include this pesticide in a cumulative risk assessment. For the purposes of this tolerance action, EPA has not assumed that propiconazole has a common mechanism of toxicity with other substances.

E. Safety Determination

The dietary exposure assessment for propiconazole showed that there were acceptable safety margins with respect to both chronic and acute exposure through the dietary consumption of propiconazole-treated commodities. The most sensitive subpopulation was children (1-2 years old) with a chronic exposure of 0.5% of the chronic reference dose of 0.0125 mg/kg bwt/day. Females 13 years and older is the only population subgroup of concern for the acute dietary exposure assessment. Dietary exposure to females (13-50 years old) at the 99.9th percentile of exposure was negligible (0.3% of the acute RfD of 0.30 mg/kg bwt/day).

EPA has determined that reliable data support using the standard MOE and uncertainty factor (100 for combined interspecies and intraspecies variability) for propiconazole and that an additional safety of 10 is not necessary to be protective of infants and children.

For the drinking water portion of the aggregate assessment, the EECs of propiconazole in surface water were greater than those for ground water. Surface water EECs were 4.69 ppb and 2.99 ppb for acute and chronic exposure, respectively. The chronic DWLOC was calculated as 129 ppb for the most sensitive subgroup, children (1-2 years old). For the acute assessment, the females 13 years and older subpopulation is the only subgroup of concern and provided an acute DWLOC of 8,972 ppb. Since both chronic and acute EECs were well below the chronic and acute DWLOCs, there should be no concern for acute risk from either surface water or ground water.

Exposure from non-food sources, residential and lawn applications of propiconazole products, is considered to be negligible. Based upon the current chronic and acute aggregate exposure analysis, aggregate exposures are below 100% of the chronic and acute reference doses. The worst-case chronic food exposure for children 1-2 years old represents 0.5% of the chronic RfD of 0.0125 mg/kg bwt/day. The worst-case chronic drinking water exposure for children 1-2 years old (based upon surface water modeling) represents 2.3% of the chronic reference dose. Since the residential exposure for propiconazole is negligible, the worst-case aggregate chronic risk (food plus drinking water) is approximately 3%. The worst-case aggregate acute risk (food plus drinking water) to females (13-50 years old) at the 99.9th percentile of exposure is negligible (0.3% of the acute RfD of 0.30 mg/kg bwt/day).

Syngenta has considered the potential aggregate exposure from food, water and non-occupational exposure routes and concluded that aggregate exposure is not expected to exceed 100% of the chronic and acute RfDs and there is a reasonable certainty that no harm will result to any populations subgroups, including infants and children, from the aggregate exposure to propiconazole.

F. International Tolerances

International CODEX values are established for almond, animal products, bananas, barley, coffee, eggs, grapes, mango, meat, milk, oat, peanut-whole, peanut grains, pecans, rape, rye, stone fruit, sugar cane, sugar beets, sugar beet tops, and wheat. The U.S. residue definition includes both propiconazole and metabolites determined as 2,4-dichlorobenzoic acid (DCBA), while the CODEX definition is for propiconazole, per se, i.e. parent only. This difference results in unique tolerance expressions with the U.S. definition resulting in the higher tolerance levels.