Docket Number EPA-HQ-OPP-2010-0923 www.regulations.gov



## Chlorpropham Summary Document Registration Review: Initial Docket

December 2010

### TABLE OF CONTENTS

I. Preliminary Work Plan (PWP) ....................................................................4

II. Fact Sheet .....................................................................................................11

III. Summary of Data Gaps...............................................................................17

________________________ ______________________ ____________________

Please Note

This Preliminary Work Plan and Fact Sheet su mmarize the Environmental Protection Agency’s current position on chlorpropham based on the following documents:

1. Registration Review: Prelim inary Problem Formulation for Environmental Fate and Ecological Risk, Endangered Species, and Dr inking Water Exposur e Assessments for Chlorpropham

. Dated November 4, 2010.

2. Chlorpropham. Human-Health Assessment Scop ing Document in Support of Registration

Review. Dated November 2, 2010.

3. Appendix A: Label, Use, and Usage Table . Dated March 5, 2010.

4. Chlorpropham: Review of Human Incidents . Dated August 20, 2010.

5. Waiver Review on Generic DCI Regarding Ch lorproham for Use on Easter Lilies and Ginkgo Trees

. Dated September 20, 2001.

6. Report of FQPA Tolerance Reassessment Pr ogress and Interim Risk Management Decision for Chlorpropham . Dated September 2002.

These and other supporting documents for the ch lorpropham registration review case may be found in the docket EPA-HQ-OPP-2010- 0923 at http://www.regulations.gov.

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### I. Preliminary Work Plan – Chlorpropham

Introduction :

The Food Quality Protection Act (FQPA) of 1996 mandated a registration review program. All pesticides distributed or sold in the United Stat es (U.S.) generally must be registered by the Environmental Protection Agency (EPA or the Ag ency), based on scientific data showing that they will not cause unreasonable ri sks 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 unreasonabl e 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 prog ram, the Agency periodically r eevaluates pesticides to make sure that as change occurs, products in the mark etplace can be used safely. Information on this program is provided at: http://www. epa.gov/oppsrrd1/registration_review/.

The Agency is implementing the registration revi ew program pursuant to Section 3(g) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), a nd will review each registered pesticide every 15 years to determine whether it continues to meet th e FIFRA standard for registration. 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 belie ves are needed to make a registration review decision. After reviewing and responding to comments and data received in the docket during this initial comment period, the Agency will de velop and commit to a final work plan and schedule for the registration review of chlorpropham.

Chlorpropham is a carbamate plant growth regulator registered for use for sprout control on postharvest, stored potatoes. Also, Special Local Need (SLN) registrations for chlorpropham allow chlorpropham use to prevent bud formation on gi nkgo trees in Washington, D.C. and to prevent

bud formation and control Botrytis on Easter lilies in California and Oregon. There are currently no residential uses for chlorpropham. The Reregistration Eligibility Decision (RED) for Chlorpropham was completed in October 1996 and the Report of FQPA Tolerance Reassessment Progress and Interim Risk Management Decision (TRED) for Chlorpropham was completed in September 2002

.

Anticipated Risk Assessment and Data Needs :

The Agency anticipates the need to require da ta and conduct an ecological risk assessment for chlorpropham, including an endangered species a ssessment. For human health, revised dietary and occupational risk assessments may be need ed during registration re view to incorporate updated toxicological endpoints, exposure estimates , and data anticipated to be required through a registration review data call-in. Below is a su mmary of the issues relevant to the registration review of chlorpropham.

4Ecological Risk:

• In past assessments, due to the limited amount of outdoor chlorpropha m use, the potential for chlorpropham to enter the environment has been assumed to be low. Consequently, the Agency has not previously conducted an environmental fate and ecological risk assessment for chlorpropham. A summary of th e available environmental fate and effects data was prepared in suppor t of the 1996 RED.

• An ecological risk assessment of all regist ered uses of chlorp ropham will be conducted during registration review. The new assessment will incorporate the most up-to-date modeling methodologies, updated toxicological endpoints, and data submitted under the anticipated registration review data call-in.

• The Agency has not conducted an ecological risk assessment that supports a complete endangered species determination for chlorp ropham. The ecological risk assessment planned during registration review will a llow the Agency to determine whether chlorpropham’s use has “no effect” or “may affect” federally listed threatened or endangered species (listed species) or thei r 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.

• Data gaps exist in the environmental fate a nd toxicity databases for chlorpropham. The Agency had previously required th rough Data Call-In Notice GDCI-018301-17712, issued in December 1996, a number of environm ental fate and ecological effects studies as confirmatory data for th e chlorpropham RED. However, the Agency waived these study requirements after the registrant voluntarily cancelle d the use of chlorpropham on spinach. The justification fo r waiving the study requirements was also based on the very limited use of chlorpropham on Easter lilies and ginkgo trees, and the determination that available data for structurally similar herbic ides, propanil and propham, could be used as surrogate data for chlorpropham. However, based on current environmental fate and ecological risk assessment standards, data are needed for the registration review assessment of chlorpropham.

• EPA anticipates requiring the following gui deline studies in order to conduct a comprehensive ecological risk assessment, in cluding an endangered species assessment, for the registration review of chlorpropham.

 Guideline No. 835.1230 – Sediment and Soil Absorption/Desorption

 Guideline No. 835.1240 – Soil Column Leaching

 Guideline No. 835.4100 – Aerobic Soil Metabolism

 Guideline No. 850.1300 – Daphnid Chronic Toxicity

 Guideline No. 850.1400 – Fish Early-Li fe Stage Toxicity, freshwater

 Guideline No. 850.2100 – Avian Acute Oral Toxicity, Passerine

 Guideline No. 850.2300 – Avian Reproduction

5 Guideline No. 850.4100 – Terrestrial Plant T oxicity: Tier 2 seedling emergence 1

 Guideline No. 850.4150 – Terrestrial Plant Toxicity: Tier 2 vegetative vigor 1

 Guideline No. 850.4400 – Aquatic Plant Toxicity, Tier 2 1

 Guideline No. 850.5400 – Algal Toxicity, Tier 2 1

• The Agency seeks additional information, particularly use and usage information, in order to conduct a refined, complete ecological risk assessment, including an endangered species assessment for chlorpropham. S ee the “Guidance for Commenters” section

below.

• Please refer to the November 4, 2010 document Registration Review: Preliminary Problem Formulation for Environmental Fate and Ecological Risk, Endangered Species, and Drinking Water Exposure Assessments for Chlorpropham in the registration review docket (EPA-HQ-OPP-2010-0923) for a detailed discussion of the anticipated risk

assessment and data needs.

Human Health Risk:

• The most recent human health risk asse ssment, including an updated drinking water assessment, was completed in 2002 in support of the chlorpropham TRED.

• During registration review, the Agency anticipates conducting a new drinking water assessment for the Easter lily use and the amount of chlorpropham that deposits from the aerial release into the environment from the stored potato use.

• The Agency anticipates conducting a new dietar y risk assessment, incorporating refined estimated drinking water concentrations (E DWCs), updated anticipated residues, and Pesticide Data Program (PDP) data.

• The chlorpropham tolerance expression will be reviewed during registration review to ensure that it appropriately covers the metabolites and de gradates of chlorpropham and that it specifies the residues to be measured for each commodity.

• The residue chemistry database is sufficient to support the current registrations; however, there are some outstanding data requirements concerning the analy tical methods. These data were required by a previous Data Call -in (DCI) for chlorpropham issued in April 1994. These data, when submitted, will complete the residue chemistry data requirements for chlorpropham. Th e overdue, outstanding data are:

1 The Agency anticipates requiring a Ti er II study. The anticipated Data Call-In Notice will note that a Tier I study may be conducted in lieu of a Tier II study with the understanding that adverse effects (even if <25%) would necessitate a Tier II study as well. The purpose of a Tier II study is to establish either a No Observed Adverse Effect Concentration (NOAEC) or a concentration at which there is a 5% observed effect (EC05) to be used in an endangered speci es risk assessment for nontarget plants. If neither an NOAEC nor an EC05 value is available, then the Agen cy may have to presume that chlorpropham “may affect” listed nontarget plant species in the regist ration review endangered species risk assessment.

6 A revised analytical method for tolerance enforcement in stored potato

commodities.

 Independent laboratory validation for the enforcement method to detect chlorpropham and its 4-HAS me tabolite in meat and milk.

• Occupational exposures have not been previ ously assessed for airb last application to ginkgo trees and for the post-appli cation use on Easter lilies. In addition, the previously assessed occupational handler exposure scenarios did not include estimates of inhalation exposure. Therefore, the Agency anticipa tes conducting a revised occupational exposure assessment during registration review.

• EPA anticipates requiring the following guide line studies in order to complete the toxicity database for chlorpropham and conduct a complete human health risk assessment for the registration review of chlorpropham:

 Guideline No. 870.3465 90-day Inhalation-Toxicity 1

 Guideline No. 870.6200 Acute and Subchronic Neurotoxicity

 Guideline No. 870.7800 Immunotoxicity

• Please refer to the November 2, 2010 document Chlorpropham. Human-Health Assessment Scoping Document in Support of Registration Review in the registration review docket (EPA-HQ-OPP-2010-0923) for a deta iled discussion of the anticipated risk

assessment and data needs.

Endocrine Disruptor Screening Program :

As required under FFDCA section 408(p), EP A has developed the Endocrine Disruptor Screening Program (EDSP) to determine whether certain substances (inc luding pesticide active and other ingredients) may have an effect in humans or wildlife si milar 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 ap proach 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 estroge n, androgen, and or thyroid (E, A, or T) hormonal systems. Chemicals that go th rough Tier 1 screening and are found to have the potential to interact with E, A, or T hormonal systems will proceed to the next stag e of the EDSP where EPA will determine which, if any, of th e Tier 2 tests are necessary base d on the available data. Tier 2 testing is designed to identify a ny adverse endocrine related eff ects caused by the substance, and establish a quantitative relationship betw een the dose and the E, A, or T effect.

Between October 2009 and February 2010, EPA issued test orders/data call-ins for the first group of 67 chemicals, which contains 58 pesticid e active ingredients and 9 inert ingredients.

This list of chemicals was selected based on th e potential for human exposure through pathways such as food and water, residen tial activity, and certain post-applic ation agricultural scenarios.

This list should not be construed as a lis t of known or likely endocrine disruptors.

1 While the inhalation guideline calls for a 90-day study duration, a 28-day study duration will satisfy the Agency’s inhalation exposure data needs.

7Chlorpropham is not among the group of 58 pesticide active ingredients on th e initial list to be

screened under the EDSP. Under FFDCA sec. 408(p) the Agency must screen all pesticide chemicals. Accordingly, EPA anticipates i ssuing future EDSP orders/data call-ins for all Registration Review cases, including those for which EPA has already opened a Registration Review docket for a pes ticide active ingredient.

For further information on the status of the ED SP, the policies and procedures, the list of 67 chemicals, the test guidelines and the Tier 1 screening battery, pleas e visit our website: http://www.epa.gov/endo/

.

Timeline :

EPA has created the following estimated timeline for the completion of the chlorpropham registration review.

Registration Review for Chlorpropham – Projected Registration Review Timeline

Activities Estimated Date Opening the Docket Open Docket and Public Comment Period 2010 – December

Close Public Comment 2011 – February Case Development

Final Work Plan 2011 – May

Issue DCI 2012 – Jan. – March

Data Submission 2014 – Jan. – March Open Public Comment Period for Draft Risk Assessments 2015 – July – Sept.

Close Public Comment Period 2015 – Oct. – Dec. Registration Review Decision Open Public Comment Period for Proposed Registration Review

Decision 2016 – Jan. – March

Close Public Comment Period 2016 – April – June Registration Review Decision and Begin Post-Decision Follow-up 2016 Total (years) 6

Guidance for Commenters :

The public is invited to comment on EPA’s preliminary work plan and rationale. The Agency will carefully consider all comments as well as any additional information or data provided in a timely manner prior to issuing a final work plan for the chlorpropham case.

Trade Irritants:

Through the registration review process, the Ag ency intends to solicit information on trade irritants and, to the extent feas ible, take steps toward facilitating irritant resolution. Growers and other stakeholders are asked to comment on any tr ade irritant issues resulting from lack of Maximum Residue Limits (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.

8Water Quality:

Chlorpropham is not identified as a cause of impair ment for any water bodies listed as impaired under section 303(d) of the Clean Water Act, based on information provided at http://iaspub.epa.gov/tmdl_waters10/attains_ nation_cy.cause_detail_303d?p_cause_group_id=88 5. In addition, no Total Maximum Daily Loads (T MDL) have been developed for chlorpropham, based on information provided at http://iaspub.epa.gov/tmdl_waters1 0/attains_nation.tmdl_pollutant_ detail?p_pollutant_group_id=885&p_pollutant_gr oup_name=PESTICIDES. More information on impaired water bodies and TMDLs can be f ound at http://www.epa.gov/owow/tmdl/. 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 Im paired Water Body and Other Water Quality Data in OPP’s Registration Review Risk A ssessment and Management Process (see http://www.epa.gov/ oppsrrd1/registration_review/water_ quality_sop.htm) in order to ensure they can be used quantitatively or qualitatively in pesticide risk assessments.

Environmental Justice:

EPA seeks to achieve environmenta l justice, the fair tr eatment and meaningful involvement of all people, regardless of race, color, national origi n, or income, in the deve lopment, implementation, and enforcement of environmental laws, regulati ons, 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 thei r location, cultural practices, or other factors, may have atypical, unusually high exposure to chlorproph am compared to the general population. Please comment if you are aware of any sub-populatio ns that may have atypical, unusually high exposure compared to the general population.

Other Information:

Stakeholders are also specifically asked to prov ide information and data that will assist the Agency in refining the risk assessments, including any species-specific ecological determinations. The Agency is interested in obtaining the following information:

1. information which may help the Agency calcu late how much chlorp ropham is released into the environment from potato storag e facilities where ch lorpropham is used

2. confirmation on the following label information

a. sites of application

b. formulations

c. application methods and equipment

d. maximum application rates

e. frequency of application, applicati on intervals, and maximum number of applications per season

f. geographic limitations on use

3. use or potential use distribution ( e.g. , acreage and geographical di stribution of relevant crops)

4. use history

95. median and 90 th percentile reported use rates (lbs ai/1000 sq ft) from usage data – national, state, and county

6. application timing (date of first application and application interval s) by crop – national, state, and county

7. sub-county crop location data

8. usage/use information for non-agricultural uses

9. directly acquired county-level usage da ta (not derived from state level data)

a. maximum reported use rate (lbs a i/acre) from usage data – county

b. percent crop treated – county

c. median and 90 th percentile number of applications – county

d. total pounds per year – county

e. the year the pesticide was last us ed in the county/sub-county area

f. the years in which the pesticide was applied in the county/sub-county area

10. typical application interval (days)

11. state or local use restrictions

12. ecological incidents (non-target plant damage and avian, fish, reptilian, amphibian and mammalian mortalities) not alr eady reported to the Agency

13. monitoring data

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 i ssue a Final Work Plan for the registration review of chlorpropham.

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### II. FACT SHEET

Background Information :

• Chlorpropham registration review case number: 0271.

• Chlorpropham PC code: 018301.

• Chlorpropham CAS No.: 101-21-3.

• Chlorpropham was first registered fo r use in the United States in 1962.

• The RED for Chlorpropham was completed in October 1996 and the TRED for Chlorpropham was completed in September 2002.

• The technical registrants for chlorpropham are Aceto Agricultural Chemicals Corporation, Decco US Post-Harvest, Inc., and Pin Nip, Division of 1,4 Group, Inc.

• There are currently thir teen end-use products and three t echnical products registered for chlorpropham. There are also 5 active state-specific Special Local Need (SLN) registrations.

• Tolerances for chlorpropham are established in 40 CFR Part 180.181.

• Pesticide Re-evaluation Divi sion, Chemical Review Mana ger: Eric Miederhoff, miederhoff.eric@epa.gov

.

• Registration Division contact: Tony Kish, kish.tony@epa.gov.

Use & Usage Information : (For additional details on label rates and use sites, refer to Appendix A: Label, Use, and Usage Table in the chlorpropham docket EPA-HQ-OPP-2010-0923.)

• Based on the percent of the volume treated and total pounds applied, chlorpropham is the top active ingredient (a.i.) used as a po st-harvest treatment on potatoes (USDA NASS, 2007). During the 2005-2006 marketing year , 168,100 pounds of chlorpropham were applied to potatoes accounting for nearly 50% of the volume treated (USDA NASS, 2007). This usage covers applications ma de in off-farm warehouses, shipping and processing facilities, and on farms with stor age facilities. Chlorpropham was also the leader when usage was previously surveyed in 1996.

• Chlorpropham may be formulated as an emulsifiable concentrate, a liquid ready-to-use, and as a solid (for use in aerosol generator/fogger).

• This chemical is applied as a post-harv est fumigation/non-fumigation treatment for potatoes. It may also be used as a broa dcast (mist) treatment on ginkgo trees or as a directed spray for field grown Easter lilies.

11Ecological Risk Assessment Status :

Please refer to the Registration Review: Preliminary Problem Formulation for Environmental Fate and Ecological Risk, Endangered Species, and Drinking Water Exposure Assessments for Chlorpropham

, dated November 4, 2010, for the most recen t ecological review of chlorpropham.

Due to the limited amount of outdoor chlorpropham use, the potential for chlorpropham to enter

the environment had been assumed to be low. Consequently, the Agency had not previously conducted an environmental fate and ecological risk assessment for chlorpropham. Rather, a summary of the available environmental fate a nd effects data was prep ared in support of the

1996 RED.

Additionally, during th e evaluation of a waiver request for a number of ecological studies, the Agency used surrogate data from two structurally similar chemi cals to perform a screening-level assessment. This assessment (please refer to Waiver Review on Generic DCI Regarding Chlorproham for Use on Easter Lilies and Ginkgo Trees

. dated September 20, 2001 for additional information) concl uded that chlorpropham may im pact endangered species of

freshwater fish and invertebrates.

Exposure Pathways :

• Based on the limited acceptable environmental fa te data, chlorpropham is expected to be mobile to moderately mobile in soils. Surface water contamination resulting from the outdoor use may be expected to occur predom inantly via spray drift and/or from the transport in runoff. Vapor pressure data suggest that one route of dissipation for chlorpropham will be volatilization.

• The geographically limited SLN Easter lily and gingko tree uses may result in chlorpropham deposition into local surface wa ter and subsequent exposure to aquatic organisms. Terrestrial organisms may be exposed through dermal uptake/ingestion, root uptake, or inhalation.

• The potato storage use may result in atmospheri c transport of chlorpropham as a vapor or aerosol. Terrestrial organisms may be expos ed to chlorpropham through ingestion, root uptake, or inhalation.

Summary of Toxicity Data :

• Chlorpropham is classified as:

 Moderately toxic to freshwat er fish and invertebrates on an acute exposure basis.

 Practically nontoxic to terre strial birds on an acute or al and subacute dietary exposure basis.

 Practically nontoxic to mammals on an acute oral exposure basis.

12 Practically nontoxic to honey bees on an acute contact exposure basis.

• No data are available on the to xicity of chlorpropham to a quatic or terrestrial plants. However, chlorpropham is a known herbicide and plant growth regulator and, thus, phytotoxic effects are considered likely.

Human Health Risk Assessment Status :

Please refer to Chlorpropham. Human-Health Assessment Scoping Document in Support of Registration Review , dated November 2, 2010, for a detailed discussion of the key findings of the

most recent human health risk assessment. A summary follows:

• Past chlorpropham risk assessments rely in part on data from st udies in which adult human subjects were intentionally exposed to a pesticide to determine their dermal and inhalation exposure. Many such studies, invo lving exposure to many different pesticides, comprise generic pesticide exposure database s such as the Pestic ide Handlers Exposure Database (PHED) and the Agricultural Reen try 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 relativ e to the ethical standards prevailing at the time the research was conducte d. All applicable re quirements of EPA’s

Rule for the Protection of Hu man Subjects of Research ( 40 CFR Part 26) have been satisfied, and there is no regulatory barri er to continued reli ance on these studies.

Hazard Characterization :

• Chlorpropham is a plant growth regulator that works by st opping cell division and plant tissue growth. Chlorpropham is classified as a carbanilate herbicide and contains a carbamate linkage, but was not found to cause c holinesterase inhibition in a reproduction study or in chronic studies in dogs and rats.

• Chlorpropham has low acute oral and dermal toxicities (Toxicity Category III for oral and IV for dermal exposure). Chlorpropham is a mild eye and skin irritant (Toxicity Category III and IV, respectively). It is not a dermal sensitizer.

• Chlorpropham is classified as a Group E chemical (i.e., no evidence of noncarcinogenicity in humans).

• Chlorpropham has an FQPA Safety Factor of 1x.

Dietary (Food and Drinking Water) :

• The most recent dietary-exposure assessment was performed in conjunction with the

TRED in 2002.

• An unrefined acute dietary-risk assessme nt was conducted for chlorpropham use on potatoes using tolerance-level residues and 100% cr op treated. Dietary-risk estimates are

13provided for the population subgroup females 13-50 years old (the only population requiring an acute assessment). This assessmen t concluded that the acute risk estimate is below the Agency’s level of concern (<100% acute population-adjusted dose (aPAD)) at

the 95 th exposure percentile (4% of the aPAD) for females 13-50 years old.

• A partially refined chronic dietary exposure assessment was performed using PDP monitoring data for potatoes and milk and anticipated residues derived from feeding

studies for other livestock commodities. This assessment concluded that for all commodities, the chronic risk estimates are below the Agency’s level of concern (<100% chronic population-adjusted dose (cPAD)) for the general U.S. population (4% of the cPAD) and all population subgroups. The ch ronic dietary exposure estimate for the highest exposed population s ubgroup, children 1-6 years ol d, is 10% of the cPAD.

• The only chlorpropham use that may result in exposure throu gh drinking water is application to Easter lilies. The Agency assessed potential exposure to water based on the Easter lily use which is limited to Curry County, Oregon and Del Norte County, California. Approximately 150 acres (1/4 squa re mile) receives treatment with chlorpropham annually. Any pot ential exposure would be lim ited to these two counties. Please refer to the 2002 chlorp ropham TRED for more information on the drinking water

assessment.

 Surface water intakes are not located near lily bulb cultivating areas; therefore, the potential for exposure to chlorpropham in su rface water sources of drinking water is negligible. The Agency concluded th at no population groups are exposed to chlorpropham residues in surface water sour ces of drinking water at a level that poses an acute or chronic risk concern.

 For acute risk from ground water sources of drinking water, potential exposure to chlorpropham from drinking water is not of concern.

 For chronic risk from ground water sources of drinking water, the Easter lily use is

not of concern.

 For carcinogenic risk, potential chroni c exposure to chlorpropham from ground water sources of drinking wate r associated with the Easter lily bulb use is estimated to range from 2.0 ppb to 8.0 ppb. This range is based on varying modeling parameters including degradation half life and assuming 100% of the parent chlorpropham is degraded to 3-chloroanaline. As such, these estimates may not be

suitable for a cancer assessment and will overestimate cancer risk. The conservative nature of the risk estimates, combined with the limited use area, gave the Agency reasonable assurance that aggr egate cancer risks are not of concern.

Residential (Non-occupational) :

• As there are no registered uses at residential sites, resident ial handler and post-application

assessments were not conducted in the most recent risk assessment.

14Occupational :

• The most recent occupational exposure asse ssment was completed in 1995 in support of the chlorpropham RED.

• The 1995 assessment included the potential fo r exposure to handlers resulting from the chlorpropham Section 24(c) use on Easter lilies. However, these handler assessments did not include estimates of inhalation exposur e. Also, handler exposure has not been previously assessed for airblast application to ginkgo trees.

The post-harvest application of chlorpr opham on potatoes can be done using either automated sprayers or a forced air distributi on method. Exposure data were not available for the automated sprayer application on potatoes. Additionally, it was assumed that the

forced air distribution method was a closed automated system; therefore, a handler

assessment on this use was not warranted.

Provided that commercial pesticide handl ers use label-required personal protective equipment (PPE), all assessed margins of exposure (MOEs) were not of concern.

• Occupational post-applic ation exposure was not assessed previously.

Cumulative :

• Although chlorpropham is a carbanilate herbic ide and contains a carbamate linkage, it

was not included in the carbamate cumulativ e risk assessment because it is not an N

methyl carbamate. Chlorpropham does not inhibit cholinesterase and, thus, does not share a common mechanism of toxicity with the N -methyl carbamate assessment group.

Incidents :

• The Agency consulted the Ecological Incident Information System and the Avian Incident Monitoring System databases for re ports of ecological incidents. Neither database reported any incide nts involving chloropropham.

• The Agency consulted the OPP Incident Data System (IDS), the Centers for Disease

Control and Prevention/National Institute for Occupational Safety and Health (CDC/NIOSH), Sentinel Even t Notification System for Occupational Risk-Pesticides (SENSOR) and the Agricultura l Health Study databases for human health incidents involving chlropropham. From 1998 to 2007, the NIOSH SENSOR database identifies seven cases that reportedly i nvolve the active ingredient chlorpropham. The health effects reported include: gastrointestinal (75%), respiratory (50%), ocular (25%), neurological (25%), and dermal (25%). Symp toms are not mutually exclusive; a patient may have many symptoms. These cases are classi fied as low to moderate severity (three as low, one as moderate). Two cases ( one occupational and one nonoccupational) were the result of drift exposure. One case involved a landscap er experiencing dermal symptoms while applying chlorpropham. On e case involved exposur e to the applicator while spraying greenhouse ornamentals.

15Tolerances and International Harmonization :

• The U.S., Mexican, Canadian, and Codex residue definitions for plant commodities are harmonized. For potatoes, the U.S. tole rance and Codex maximum residue limits (MRLs) are harmonized; however, the U.S. to lerance level and the Canadian MRL for residues in/on potato are not ha rmonized (U.S.: 30 ppm vs. Canadian: 15 ppm). Only

the U.S. has a tolerance established for re sidues in/on potato processed products (wet peel). For livestock commodities, the Code x tolerance expression is not harmonized and

the MRLs are set at different levels for cattle meat, byproducts, and milk (i.e., U.S. meat: 0.06 ppm vs. Codex MRLs cover cattle commod ities and are established for residues in fat and kidney, while U.S. tolerances cover commodities from cattle, goats, hogs, horses, and sheep). Canadian MRLs are not established for residues in livestock commodities

and are therefore not harmonized.

Data Call-In Status :

• Generic data call-ins (GDC I-018301-17113, GDCI-018301-17712, and GDCI-018301- 17906) were issued in April 1994, December 1996, and December 2003, respectively, to provide data for the 1996 Chlorpropham RE D and the 2002 TRED. Analytical method data from Guideline Nos. 171-4d and 171-4j are overdue and remain outstanding from GDCI-018301-17113. All data requirements fr om subsequent data call-ins for chlropropham have been fulfilled.

Labels :

• Labels can be obtained from the Pesticid e Product Label System (PPLS) website: http://oaspub.epa.gov/pestlabl/ppls.home

.

1617 III. Summary of Data Gaps – Chlorpropham

The table below summarizes all anticipa ted and previously required data for chlorpropham in Section I of this document (Preliminary Work Plan), the Registration Review: Preliminary Problem Formulati on for Environmental Fate an d Ecological Risk, Endangered Species, and Drinking Water Exposure Assessments for Chlorpropham

, dated November 4, 2010, and the Chlorpropham. Human-Health Assessm ent Scoping Document in Support of Registration Review dated November 2, 2010.

Guideline

Number Data Needs Test

Material Estimated

Timeframe

ANTICIPATED REGISTRATION REVIEW DCI STUDIES

870.3465 90-Day Inhalation Toxicity 1 TGAI 24

870.6200 Acute and Subchronic Neurotoxicity TGAI 24

870.7800 Immunotoxicity TGAI 12

835.1230 Sediment and soil absorption/desorption for parent and degradates TGAI 12

835.1240 Soil Column Leaching TGAI 12

835.4100 Aerobic Soil Metabolism TGAI 24

850.2100 Avian Acute Oral Toxicity, passerine TGAI 12

850.4100 Terrestrial Plant Toxicity, Tier II (seeding emergence) 2 TGAI 12

850.4150 Terrestrial Plant Toxicity, Tier II (vegetative vigor) 2 TGAI 12

850.4400 Aquatic Plant Toxicity, Tier 2 2 TGAI 12

850.5400 Algal Toxicity, Tier 2 2 TGAI 12

850.2300 Avian Reproduction TGAI 24

850.1300 Daphnid Chronic Toxicity TGAI 12

850.1400 Fish Early-Life Stage Toxicity, freshwater TGAI 12

OUTSTANDING DATA FROM GDCI-018301-17113

171-4d Res. analyt. method - animal 12
171-4j Mag. Meat/milk/poultry/egg 18

1 While the inhalation guideline calls for a 90-day study duration, a 28-day study duration will satisfy the Agency’s inhalation exposure data needs.

2 The Agency anticipates requiring a Ti er II study. The anticipated Data Call-In Notice will note that a Tier I study may be conducted in lieu of a Tier II study with the understanding that adverse effects (even if <25%) would necessitate a Tier II study as well. The purpose of a Tier II study is to establish either a No Observed Adverse Effect Concentration (NOAEC) or a concentration at which there is a 5% observed effect (EC05) to be used in an endangered speci es risk assessment for nontarget plants. If neither an NOAEC nor an EC05 value is available, then the Agen cy may have to presume that chlorpropham “may affect” listed nontarget plant species in the regist ration review endangered species risk assessment.