2

Kresoxim-methyl Preliminary Work Plan – Table of Contents 

Overview 3 

Anticipated Data Needs 4 

Statutory and Regulatory Authority 4 

Chemical Facts 5 

Use and Usage Information 5 

Recent Actions 6 

Anticipated Risk Assessments for Registration Review 6 

Timeline 9 

Next Steps 9 

Appendix – Additional Areas Considered in Kresoxim-methyl’s Registration Review 10 

References:

This Preliminary Work Plan summarizes the Environmental Protection Agency's current position 

based on the following documents: 

1. Registration Review: Preliminary Problem Formulation for Environmental Fate and 

Ecological Risk, Endangered Species, and Drinking Water Assessments for Kresoximmethyl. Elizabeth Riley, Iwona Maher. November 20, 2012. 

2. Kresoxim-methyl. Human Health Assessment Scoping Document in Support of 

Registration Review. Myron S. Ottley, Meheret Negussie, Nancy Tsaur. November 30, 

2012. 

3. BEAD Chemical Profile for Registration Review: Kresoxim-methyl (129111). Carl Chen, 

Rafael Prieto, John Faulkner. June 5, 2012. 

4. Kresoxim-methyl: Review of Human Incidents. Shanna Recore. October 9, 2012.

These and other supporting documents for the kresoxim-methyl registration review case may be 

found in the docket EPA-HQ-OPP-2012-0861 at http://www.regulations.gov. 
3

OVERVIEW

The docket for kresoxim-methyl is now open, initiating the first public comment period for this 

registration review (docket number EPA-HQ-OPP-2012-0861). Kresoxim-methyl is a fungicide 

in the strobilurin class that inhibits spore germination, sporulation, and mycelia growth on leaf 

surfaces. It is registered for use on pome fruits, cucurbits, grapes, pecans, commercial 

greenhouses, shade and lath-houses, outdoor nurseries and non-residential landscape areas. This 

Preliminary Work Plan (PWP) document explains what EPA's Office of Pesticide Programs 

knows about kresoxim-methyl, highlighting anticipated data and assessment needs, identifying 

the types of information that would be especially useful to the Agency in conducting the review, 

and providing an anticipated timeline for completing kresoxim-methyl’s review. 

 

The registration review process was designed to include a public participation component to 

solicit input from interested stakeholders. The Agency intends, by sharing this information in the 

docket, to inform the public of what it knows about kresoxim-methyl and what types of new data 

or other information would be helpful for the Agency to receive as it moves toward a decision on 

kresoxim-methyl. The Agency encourages all interested stakeholders to review the PWP and 

Appendix and to provide comments and additional information that will help the Agency’s 

decision-making process for this chemical. In addition to general areas on which persons may 

wish to comment, there are some areas identified in the PWP and Appendix about which the 

Agency specifically seeks comments and information. Interested stakeholders could include: 

environmental non-profit or interest groups; pesticide manufacturers; agricultural labor or 

commodity groups; commercial, institutional, residential, and other users of pesticides; or the 

public at large. 

The PWP begins by listing the anticipated data needs for kresoxim-methyl. Next, it discusses the 

statutory and regulatory authority for Registration Review. Then the document provides 

kresoxim-methyl’s chemical facts, use and usage information, recent actions, the anticipated risk 

assessments, and a projected registration review timeline. Finally, the Appendix to this 

document includes identification and discussion of some areas that are considered generally in 

Registration Review along with some additional chemical case-specific information. 

 
4

ANTICIPATED DATA NEEDS

Table 1 below summarizes anticipated data needs for kresoxim-methyl. For additional 

discussion of the anticipated data needs, see the Registration Review: Preliminary Problem 

Formulation for Environmental Fate and Ecological Risk, Endangered Species, and Drinking 

Water Assessments for Kresoxim-methyl and Kresoxim-methyl. Human Health Assessment 

Scoping Document in Support of Registration Review. 

Table 1: Anticipated Data Needs for Kresoxim-methyl’s Registration Review 

Guideline 

Number Study Title Test 

Material 

Estimated 

Timeframe 

(Months from 

receipt of DCI) 

850.1350 Aquatic Invertebrate Chronic Life Cycle (saltwater) TGAI 12 

850.1400 Fish Early-Life Stage (saltwater) TGAI 12 

850.2100 Avian Acute Oral (passerine species) TGAI 12 

860.1340 Residue Analytical Method TGAI 24 

870.7800 Immunotoxicity TGAI 12 

TGAI = technical grade active ingredient 

STATUTORY AND REGULATORY AUTHORITY

The Food Quality Protection Act (FQPA) of 1996 mandated a registration review program. All 

pesticides distributed or sold in the United States (U.S.) generally must be registered by the 

Environmental Protection Agency (EPA or the Agency), based on scientific data showing that 

they will not cause unreasonable risks to human health or the environment when used as directed 

on product labeling. The registration review program is intended to make sure that, as the ability 

to assess risk evolves and as policies and practices change, all registered pesticides continue to 

meet the statutory standard of no unreasonable adverse effects to human health or the 

environment. Changes in science, public policy, and pesticide use practices will occur over time. 

Through the registration review program, the Agency periodically reevaluates pesticides to make 

sure that as change occurs, products in the marketplace can be used safely. Information on this 

program is provided on EPA’s website1

. 

The Agency is implementing the registration review program pursuant to Section 3(g) of the 

Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), and will review each registered 

pesticide every 15 years to determine whether it continues to meet the FIFRA standard for 

registration. The regulations governing registration review begin at 40 CFR 155.40. The 

Agency will consider benefits information and data as required by FIFRA. The public phase of 

registration review begins when the initial docket is opened for each case. The docket is the 

Agency’s opportunity to state what it knows about the pesticide and what additional risk analyses 

and data or information it believes are needed to make a registration review decision. After 

 

1

 http://www.epa.gov/oppsrrd1/registration_review/ 
5

reviewing and responding to comments and data received in the docket during this initial 

comment period, the Agency will develop a Final Work Plan (FWP) and anticipated schedule for 

the registration review of kresoxim-methyl. Table 2 provides a summary of the current 

regulatory status of kresoxim-methyl. 

Table 2: KRESOXIM-METHYL CHEMICAL FACTS 

PC code 129111 

Case Number 7026 

CAS Number 143390-89-0 

Year first registered 1998 

Pesticide Type Fungicide 

Chemical class Strobilurin 

Reregistration Eligibility 

Decision (RED) 

Kresoxim-methyl was registered after November 1984, and 

therefore was not subject to reregistration. 

Tolerance Reassessment 

Decision (TRED) 

Not applicable 

Cumulative group Not applicable 

40 CFR Citation Tolerances for kresoxim-methyl are established in 40 CFR 180.554. 

Dual-use Conventional pesticidal uses only. 

Non-pesticidal uses No non-pesticidal uses of kresoxim-methyl. 

Pesticide Re-evaluation 

Division, Chemical 

Review Manager 

Katie Weyrauch, weyrauch.katie@epa.gov, (703) 308-0166 

Registration Division, 

Product Manager 

Mary Waller, waller.mary@epa.gov, (703) 308-9354 

USE AND USAGE INFORMATION

Table 3 summarizes the use and usage information for kresoxim methyl. Please see the BEAD 

Chemical Profile for Registration Review: Kresoxim-methyl (129111) in the registration review 

docket for more details. 

Table 3: USE AND USAGE INFORMATION 

Summary of Use Kresoxim-methyl is a systemic fungicide in the strobilurin class. 

Kresoxim-methyl inhibits spore germination, sporulation, and 

mycelia growth on the leaf surface, and is registered to control 

diseases such as apple scab and powdery mildew. 

Use Sites Registered for use on agricultural and non-agricultural use sites, 

including pome fruit, grapes, pecans, cucurbits, and ornamental 

plants in nurseries and greenhouses. 

Summary of Usage From 2006-2010, kresoxim-methyl’s annual agricultural usage 

averaged 30,000 pounds of active ingredient, treating an average of 

250,000 acres. The average application rate was 0.12 pounds active 

ingredient per acre. 

Formulation Type Water dispersible granules 

Application Methods Ground, aerial, manually pressurized handwand, and hose-end 
6

sprayer 

Technical Registrant BASF Corporation 

No. of Registrations 4 Section 3 product registrations; 2 technical and 2 end-use 

products2

. 

Restricted Use No 

Guidance for Commenters: Additional areas of use and usage related information

requested for this registration review, and of particular interest to EPA, are described below. 

 Certain kresoxim-methyl labels are unclear with respect to application parameters like the 

size of the treated area, the extent of a treated “spot,” retreatment intervals, or maximum 

annual application rates. EPA expects to approximate these parameters in order to 

conduct a quantitative assessment for kresoxim-methyl. The Agency will work with 

registrants to clarify kresoxim-methyl product labels. 

 Confirmation of the following label information: sites of application; formulations; 

application methods and equipment; maximum application rates; frequency of 

application, application intervals, and maximum number of applications per season; and 

geographic limitations on use. 

 Use distribution (e.g., acreage and geographical distribution of relevant use sites) 

 Median and 90th percentile reported use rates (lbs ai/acre) from usage data – national, 

state, and county 

 Application timing (date of first application and application intervals) – national, state, 

and county 

 Usage/use information for non-agricultural uses 

 Typical application retreatment interval (days) 

 State or local use restrictions 

 Foreign technical registrants not listed above who supply technical kresoxim-methyl to 

the US market 

RECENT ACTIONS

A new use on cucurbits was registered in 2006 (71 FR 50354; FRL-8088-1). 

ANTICIPATED RISK ASSESSMENTS FOR REGISTRATION REVIEW

The most recent comprehensive human health risk assessment for kresoxim-methyl was 

completed on July 26, 2006 to support the registration of kresoxim-methyl on cucurbits. The 

most recent ecological and environmental fate risk assessment was completed July 12, 2006 for 

the same purpose. Findings and conclusions from these risk assessments are summarized in the 

Registration Review: Problem Formulation for the Environmental Fate, Ecological Risk, 

Endangered Species, and Drink Water Exposure Assessment for Kresoxim-methyl and Kresoximmethyl: Human Health Assessment Scoping Document in Support of Registration Review. 

 

2

 Section 3 product labels can be obtained from the Pesticide Product Label System (PPLS) website 

(http://oaspub.epa.gov/pestlabl/ppls.home). 
7

During registration review, the Agency anticipates the need to conduct a comprehensive 

ecological risk assessment, including an endangered species assessment, for all uses of kresoximmethyl. For human health, EPA anticipates the need to conduct a revised dietary risk assessment 

during registration review as all future drinking water estimates will be based on separate 

assessments for kresoxim-methyl and its degradate, BF 490-1 in accordance with new Agency 

policy and guidance. If toxicological endpoints or points of departure are revised based on the 

data that are anticipated to be required for registration review, they will be considered in the new 

assessments, as well as any changes to the standard operating procedures or default exposure 

assumptions. 

Table 4 summarizes the anticipated registration review risk assessments based on the EFED 

Problem Formulation and HED Scoping Document. 

Table 4: Anticipated Risk Assessments for Kresoxim-methyl’s Registration Review 

Type of Risk Assessment Conduct? Notes 

Ecological and Environmental Fate 

Comprehensive ecological 

(species to be assessed 

include terrestrial and aquatic 

organisms), including 

endangered species 

Y - 

Incidents N No incidents were reported in either the ecological 

incident information system (EIIS) or the avian 

monitory system (AIMS) databases. For additional 

discussion of kresoxim-methyl’s reported ecological 

incidents, see page 14 of the Problem Formulation. 

Human Health 

Dietary 

Food Y The need for a new dietary assessment will be 

dependent on whether drinking water estimates are 

revised. Furthermore, although a new version of 

DEEM (Version 3.16) has been released, a new 

dietary risk assessment may not be needed since it is 

anticipated that the changes in the model will not 

affect the risk conclusion. 

Drinking water Y In accordance with Agency policy, kresoxim-methyl 

and its degradate, BF 490-1, will be assessed 

separately for future drinking water assessments. 

Therefore, if the estimated drinking water 

concentrations are revised, a new drinking water 

assessment may be conducted. 

Occupational 
8

Handlers (mixers, loaders, 

applicators) 

Y A new cancer handler risk assessment may be needed 

to include all of the registered crops, while accounting 

for changes in occupational assessment policy (i.e., 

unit exposures, body weights, and expected lifespan). 

Post-application Y A new cancer post-application risk assessment may 

be needed to include all of the registered crops, while 

accounting for changes in occupational assessment 

policy (i.e., transfer coefficients, body weights, and 

expected lifespan). 

Residential 

Handlers N There are no registered residential uses associated 

with kresoxim-methyl. Therefore, a residential 

handler assessment is not required. 

Post-application Y A cancer residential post-application exposure 

assessment was not previously performed. In 

accordance with the revised residential SOPs, a 

residential post-application risk assessment is needed 

to assess potential exposure resulting from contact 

with treated retail ornamentals. Revised assessment 

will account for changes in SOPs (i.e., transfer 

coefficients, body weight and expected lifespan). 

Other 

Aggregate Y Evaluates the combined risk from dietary and 

residential exposures. If there are changes to the 

dietary or residential estimates, a revised aggregate 

assessment may be preformed. 

Cumulative N Kresoxim-methyl does not appear to produce a toxic 

metabolite produced by other substances. EPA has 

not made a common mechanism of toxicity finding as 

to kresoxim-methyl and any other substance. 

Tolerances Y The data requirement for multi-residue methods is 

fulfilled; however, the methods are not suitable for 

enforcement of tolerances. 

Incidents N Based on low frequency and severity of incident cases 

reported for kresoxim-methyl, there does not appear 

to be a concern at this time that would warrant further 

investigation. The Agency will continue to monitor 

the incident information and if a concern is raised, 

additional analysis will be included in a risk 

assessment. For a discussion of kresoxim-methyl 

reported human incidents, see page 10 of the Scoping 

Document. 

Guidance for Commenters: Additional ecological information requested for this 

registration review, and of particular interest to EPA, is described below. 
9

 Ecological incidents (non-target plant damage and avian, fish, reptilian, amphibian and 

mammalian mortalities) not already reported to the Agency. 

 Water quality monitoring data (see Appendix for further details). 

TIMELINE

EPA has created the following estimated timeline for the completion of kresoxim-methyl’s 

registration review in Table 5 below. 

Table 5: Registration Review for Kresoxim-methyl – Projected Registration Review 

Timeline

Activities Estimated Date 

Opening the Docket 

Open Docket and 60-day Public Comment Period 2012 – December 

Close Public Comment 2013 – February 

Case Development 

Final Work Plan 2013 – May 

Issue DCI 2014 – Jan – March 

Data Submission 2016 – Jan – March 

Open 30-day Public Comment Period for Draft Risk Assessments 2017 – July – Sept 

Registration Review Decision 

Open 60-day Public Comment Period for Proposed Registration Review 

Decision 

2018 – Jan – March 

Registration Review Decision and Begin Post-Decision Follow-up 2018 

Total (years) 6 

NEXT STEPS

After the 60-day public comment period closes, the Agency will review and respond to any 

comments received in a timely manner and then issue a Final Work Plan for the registration 

review of kresoxim-methyl. 

 
10

Appendix – Additional Areas Considered in Kresoxim-methyl’s Registration 

Review

PUBLIC COMMENTS AND FEEDBACK:

Guidance for Commenters: The areas below highlight topics of special interest to the Agency 

where your comments, data submissions, or reference to sources of additional information could 

be of particular use.

Trade Irritants: 

Through the registration review process, the Agency intends to solicit information on trade 

irritants and, to the extent feasible, take steps toward facilitating irritant resolution. The Agency 

will work to harmonize tolerances and international maximum residue limits (MRLs) and may 

modify tolerance levels to do so, when possible. Growers and other stakeholders are asked to 

comment on any trade irritant issues resulting from lack of MRLs or disparities between U.S. 

tolerances and MRLs in key export markets, providing as much specificity as possible regarding 

the nature of the concern. 

Water Quality: 

Kresoxim-methyl is not identified as a cause of impairment for any water bodies listed as 

impaired under section 303(d) of the Clean Water Act3

. In addition, no Total Maximum Daily 

Loads (TMDL) have been developed for kresoxim-methyl4. More information on impaired 

water bodies and TMDLs can be found at the Agency’s website5. The Agency invites 

submission of water quality data for this pesticide. To the extent possible, data should 

conform to the quality standards in Appendix A of the OPP Standard Operating Procedure: 

Inclusion of Impaired Water Body and Other Water Quality Data in OPP’s Registration Review 

Risk Assessment and Management Process6 in order to ensure they can be used quantitatively or 

qualitatively in pesticide risk assessments. 

Environmental Justice: 

EPA seeks to achieve environmental justice, the fair treatment and meaningful involvement of all 

people, regardless of race, color, national origin, or income, in the development, implementation, 

and enforcement of environmental laws, regulations, and policies. To help address potential 

environmental justice issues, the Agency seeks information on any groups or segments of the 

population who, as a result of their location, cultural practices, or other factors, may have 

atypical, unusually high exposure to kresoxim-methyl compared to the general population. 

Please comment if you are aware of any sub-populations that may have atypical, unusually 

high exposure compared to the general population.

 

3 http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885

4

http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_id=885&p_pollutant_

group_name=PESTICIDES

5 http://www.epa.gov/owow/tmdl/

6 http://www.epa.gov/oppsrrd1/registration_review/water_quality_sop.htm
11

ENDANGERED SPECIES:

A risk assessment that supports a complete endangered species determination has not been 

conducted for kresoxim-methyl. The ecological risk assessment planned during registration 

review will allow the Agency to determine whether kresoxim-methyl’s use has “no effect” or 

“may affect” federally listed threatened or endangered species (listed species) or their designated 

critical habitats. When an assessment concludes that a pesticide’s use “may affect” a listed 

species or its designated critical habitat, the Agency will consult with the U.S. Fish and Wildlife 

Service and/or National Marine Fisheries Service (the Services), as appropriate. 

ENDOCRINE DISRUPTOR SCREENING PROGRAM: 

As required by FIFRA and FFDCA, EPA reviews numerous studies to assess potential adverse 

outcomes from exposure to chemicals. Collectively, these studies include acute, subchronic and 

chronic toxicity, including assessments of carcinogenicity, neurotoxicity, developmental, 

reproductive, and general or systemic toxicity. These studies include endpoints which may be 

susceptible to endocrine influence, including effects on endocrine target organ histopathology, 

organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, 

and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and 

chronic studies that assess growth, developmental and reproductive effects in different 

taxonomic groups. As part of its most recent registration decision for kresoxim-methyl, EPA 

reviewed these data and selected the most sensitive endpoints for relevant risk assessment 

scenarios from the existing hazard database. However, as required by FFDCA section 408(p), 

kresoxim-methyl is subject to the endocrine screening part of the Endocrine Disruptor Screening 

Program (EDSP). 

EPA has developed the EDSP to determine whether certain substances (including pesticide 

active and other ingredients) may have an effect in humans or wildlife similar to an effect 

produced by a “naturally occurring estrogen, or other such endocrine effects as the Administrator 

may designate.” The EDSP employs a two-tiered approach to making the statutorily required 

determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a 

chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or T) hormonal 

systems. Chemicals that go through Tier 1 screening and are found to have the potential to 

interact with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPA 

will determine which, if any, of the Tier 2 tests are necessary based on the available data. Tier 2 

testing is designed to identify any adverse endocrine-related effects caused by the substance, and 

establish a dose-response relationship between the dose and the E, A, or T effect. 

Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between 

October 2009 and February 2010, EPA issued test orders/data call-ins for the first group of 67 

chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. Kresoximmethyl is not among the group of 58 pesticide active ingredients on the initial list to be screened 

under the EDSP. Accordingly, as part of registration review, EPA will issue future EDSP 

orders/data call-ins, requiring the submission of EDSP screening assays for kresoxim-methyl. 

For further information on the status of the EDSP, the policies and procedures, the list of 67 
12

chemicals, future lists, the test guidelines and the Tier 1 screening battery, please visit our 

website7. 

HUMAN STUDIES:

Occupational 

Past kresoxim-methyl risk assessments rely in part on data from studies in which adult human 

subjects were intentionally exposed to a pesticide to determine their dermal and inhalation 

exposure. Many such studies, involving exposure to many different pesticides, comprise generic 

pesticide exposure databases such as the Pesticide Handlers Exposure Database (PHED) and the 

Agricultural Reentry Task Force (ARTF) Database. EPA has reviewed all the studies supporting 

these multi-pesticide generic exposure databases, and has found no clear and convincing 

evidence that the conduct of any of them was either fundamentally unethical or significantly 

deficient relative to the ethical standards prevailing at the time the research was conducted. All 

applicable requirements of EPA’s Rule for the Protection of Human Subjects of Research (40 

CFR Part 26) have been satisfied, and there is no regulatory barrier to continued reliance on 

these studies. 

 

7 http://www.epa.gov/endo/