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                 Proposed Interim Registration Review Decision
                               Case Number 7223
                                       
                                       
                                 December 2020
                                       
                                       
                                                                   Approved by:
  

Mary Elissa Reaves, Ph.D.

Acting Director

Pesticide Re-evaluation Division
                                                                          Date:
      12-17-2020
                                       
                                       
                                       
			
                               Table of Contents

I.	INTRODUCTION	3
B.	Summary of Public Comments on the Draft Risk Assessments and Agency Responses	5
II.	USE AND USAGE	8
III.	SCIENTIFIC ASSESSMENTS	9
A.	Human Health Risks	10
1.	Risk Summary and Characterization	10
2.	Human Incidents and Epidemiology	12
3.	Tolerances	13
4.	Human Health Data Needs	14
B.	Ecological Risks	15
1.	Risk Summary and Characterization	15
2.	Ecological Incidents	18
3.	Ecological and Environmental Fate Data Needs	18
A.	Proposed Risk Mitigation and Regulatory Rationale	19
1.	Occupational Handlers	19
B. Label Cleanup	22
1.  Non-Target Organism Advisory Statement	23
2.	Herbicide Resistance Management	23
3.	Spray Drift Management	24
4.	Tolerance Actions	25
5.	Proposed Interim Registration Review Decision	25
6.	Data Requirements	26
IV.	NEXT STEPS AND TIMELINE	26
A.	Proposed Interim Registration Review Decision	26
B.	Implementation of Mitigation Measures	26
Appendix A:  Summary of Proposed Actions for Dimethenamid/-p	27
Appendix B:  Proposed Labeling Changes for Dimethenamid/-p Products	28
Appendix C:  Endangered Species Assessment	36
Appendix D: Endocrine Disruptor Screening Program	38


INTRODUCTION
	
This document is the Environmental Protection Agency's (EPA or the Agency) Proposed Interim Registration Review Decision (PID) for dimethenamid and dimethenamid-p (PC Code 129051 and 120051; Case 7223) and is being issued pursuant to 40 CFR §§ 155.56 and 155.58. (In this PID, the Agency uses a shorthand when referring to dimethenamid and dimethenamid-p together unless otherwise noted: dimethenamid/-p.  If reference is made to one or the other active ingredient in Case 7223, the Agency uses either "dimethenamid" or "dimethenamid-p," as appropriate). A registration review decision is the Agency's determination whether a pesticide continues to meet, or does not meet, the standard for registration in the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). The Agency may issue, when it determines it to be appropriate, an interim registration review decision before completing a registration review. Among other things, the interim registration review decision may determine new risk mitigation measures are necessary, lay out interim risk mitigation measures, identify data or information required to complete the review, and include schedules for submitting the required data, conducting the new risk assessment and completing the registration review. Additional information on dimethenamid/-p, can be found in EPA's public docket (EPA-HQ-OPP-2015-0803) at www.regulations.gov. Since 2000, all new crop use registrations for this case have been for dimethenamid-p, and therefore this document focuses primarily on the active ingredient dimethenamid-p.

FIFRA, as amended by the Food Quality Protection Act (FQPA) of 1996, mandates the continuous review of existing pesticides. All pesticides distributed or sold in the United States must be registered by EPA based on scientific data showing that they will not cause unreasonable risks to human health or to the environment when used as directed on product labeling. The registration review program is intended to make sure that, as the ability to assess and reduce risk evolves and as policies and practices change, all registered pesticides continue to meet the statutory standard of no unreasonable adverse effects. Changes in science, public policy, and pesticide use practices will occur over time. Through the registration review program, the Agency periodically re-evaluates pesticides to make sure that as these changes occur, products in the marketplace can continue to be used safely. Information on this program is provided at http://www.epa.gov/pesticide-reevaluation. In 2006, the Agency implemented the registration review program pursuant to FIFRA § 3(g) and will review each registered pesticide every 15 years to determine whether it continues to meet the FIFRA standard for registration.

The EPA is issuing a PID for dimethenamid/-p so that it can (1) move forward with aspects of the registration review that are complete and (2) implement interim risk mitigation (see Appendices A and B). The Agency is currently working with the U.S. Fish and Wildlife Service and the National Marine Fisheries Service (collectively referred to as, "the Services") to improve the consultation process for national threatened and endangered (listed) species for pesticides in accordance with the Endangered Species Act (ESA) § 7. Therefore, although EPA has not yet fully evaluated risks to federally-listed species, the Agency will complete its listed species assessment and any necessary consultation with the Services for dimethenamid/-p prior to completing the dimethenamid/-p registration review. Likewise, the Agency will complete endocrine screening for dimethenamid/-p, pursuant to the Federal Food, Drug, and Cosmetic Act (FFDCA) § 408(p), before completing registration review. See Appendices C and D, respectively, for additional information on the listed species assessment and the endocrine screening for the dimethenamid/-p registration review.

Dimethenamid was first registered in the United States in 1993, where as dimethenamid-p was first registered in the U.S. in 1999. Products containing these active ingredients are registered as selective, systemic herbicides for the control of sedges, annual grasses, and broadleaf weeds in a wide range of agricultural and non‐agricultural use sites. Both dimethenamid and dimethenamid-p are used on major agricultural use sites including crops such as field corn, grain sorghum, soybean, dry beans, peanuts, and potatoes. Both are registered for use on grass grown for seed. Dimethenamid-p is also used on major non‐agricultural use sites including landscape and grounds maintenance areas, tree plantations, turf‐grass areas, golf courses, ornamental gardens, and commercial ornamental production sites. Since 2000, all new FIFRA Section 3 crop use registrations have been formulated with dimethenamid‐p. According to the classification of herbicides, dimethenamid/‐p belong to the family of chloroacetamide herbicides.
 
This document is organized into five sections: Introduction, which includes this summary and a summary of public comments and EPA's responses; Use and Usage, which describes how and why dimethenamid/-p is used and summarizes data on its use; Scientific Assessments, which summarizes EPA's risk and benefits assessments, updates or revisions to previous risk assessments, and provides broader context with a discussion of risk characterization; Proposed Interim Registration Review Decision, which describes the mitigation measures proposed to address risks of concern and the regulatory rationale for EPA's PID; and, lastly, Next Steps and Timeline for completion of this registration review.

       Summary of Dimethenamid/-p Registration Review
   
   Pursuant to 40 CFR § 155.50, EPA formally initiated registration review for dimethenamid/-p with the opening of the registration review docket for the case. The following summary highlights the docket opening and other significant milestones that have occurred thus far during the registration review of dimethenamid/-p.

 July 2016 - The Dimethenamid and Dimethenamid/-p Preliminary Work Plan (PWP),                       Problem Formulation for the Ecological Risk and Drinking Water Exposure Assessments to be Conducted For the Registration Review of Dimethenamid and Dimethenamid-p and  Dimethenamid/Dimethenamid-P. Human Health Assessment Scoping Document in Support of Registration Review, along with other supporting documents, were posted to the docket for a 60-day public comment period. 

 November 2016 - The Dimethenamid and Dimethenamid-p Final Work Plan (FWP) for dimethenamid/-p was issued. The FWP identified data needs for the registration review of dimethenamid/-p.  
      
 August 2017 - Generic Data Call-Ins (GDCIs)--GDCI-129051-1652 (dimethenamid) and GDCI-120051-1651 (dimethenamid-p) --were issued for data needed to conduct the registration review risk assessments. All data requirements have been satisfied, with the exception of the higher tier honeybee data required by the dimethenamid GDCI. See Section III for details.

 September 2020 - The Agency announced the availability of Dimethenamid/ Dimethenamid-p: Draft Ecological Risk Assessment for Registration Review and Dimethenamid/Dimethenamid-P: Draft Human Health Risk Assessment for Registration Review, along with other supporting documents, for a 60-day public comment period. During the comment period, EPA received comments from BASF, the National Cotton Council, National Agricultural Aviation Association, and the United States Department of Agriculture. These comments and the Agency's responses are summarized below. The comments did not change the conclusions in the risk assessments or registration review timeline for dimethenamid/-p.

 December 2020 - The Agency has completed the Proposed Interim Decision for dimethenamid/-p. The PID, along with other supporting documents, is posted to the docket for a 60-day public comment period. 

       Summary of Public Comments on the Draft Risk Assessments and Agency Responses 

During the 60-day public comment period for the dimethenamid/-p Draft Risk Assessments, which opened on September 2, 2020 and closed on November 1, 2020, the Agency received public comments from 4 sources. Comments were submitted by BASF (technical registrant), National Cotton Council (NCC), National Agricultural Aviation Association (NAAA), and the United States Department of Agriculture (USDA). Substantive comments, comments of a broader regulatory nature, and the Agency's responses to those comments are summarized below. The Agency thanks all commenters for their comments and has considered them in developing this PID.
 
Comments Submitted by BASF in Document ID: EPA-HQ-OPP-2015-0803-0024 

Comment:  BASF commented on potential risks of concern the Agency identified for specific occupational handler scenarios, and proposed risk mitigation measures to address those risks.  The registrant supplemented these comments in subsequent discussions with the Agency.

BASF also requested clarification on whether or not the Agency's human health risk assessment used the orchard/vineyard scenario to represent the use of dimethenamid-p on hops (neither active ingredient in this case is registered for use on orchard crops or vineyards).

The registrant also addressed the need for a subchronic inhalation study in the context of established waiver criteria and the need for higher tier pollinator data. 

EPA Response:  EPA considered BASF's proposals for addressing occupational handler risks in developing this PID. These proposals are discussed in detail in in Section IV of this document. 
The Agency is confirming the use of the orchard/vineyard scenario as surrogate for hops, and thanks BASF for its willingness to work with the Agency on the issues presented in these comments. 

Subchronic inhalation data were not included in the registration review DCIs for dimethenamid/-p and are not currently required, but the Agency will consider BASF's comments as it prepares for future assessments of dimethenamid/-p. 

Comments Submitted by USDA in Document ID: EPA-HQ -OPP-2015-0803-0022

Comment: USDA provided updated usage data for dimethenamid/-p. The comments also discussed uncertainties in the assessment of risks for handlers in nursery scenarios, and suggested that Agency assumptions about the amount of dimethenamid/-p impregnated fertilizer processed in an 8-hour period overstate potential exposures to mixer/loaders involved in the process. While USDA acknowledges that there is no readily available information regarding how much impregnated fertilizer is handled in a day, it suggests that 640 tons is a more reasonable assumption than the 960 tons that was used in EPA's assessment. USDA calculated that, at the lower rate, risks to mixer/loaders exposed during the fertilizer-impregnation process would not be of concern. Alternatively, USDA proposed that a combination of both engineering controls and Personal Protective Equipment (PPE) could be used to reduce mixer/loader exposures during the impregnation process.

EPA Response: EPA acknowledges and thanks USDA for its comments and continued outreach to stakeholders and growers. The uncertainty USDA referred to in the assessment of risks to handlers in the nursery scenario is a 10X factor based on the absence of subchronic inhalation toxicity data. Without those data, the Agency is not able to refine the hazard assessment for dimethenamid/-p. Additionally, the Agency does not have access to information about the amount of impregnated fertilizer processed by handlers on a daily basis with which to refine handler risks in that scenario. The Agency took a different approach than the one suggested by USDA after consulting with an agricultural retailer about the blending and customization of fertilizers for growers. The Agency is proposing to address the potential risks to handlers based on information provided by the agricultural retailer and a proposal from BASF, as discussed in Section IV. 
 
Comment: USDA asked for confirmation about what model the Agency used for estimating drinking water exposures and noted that monitoring data indicate that dimethenamid/-p has been found in water at concentrations at several orders of magnitude below EPA's modeled EDWCs.

EPA Response: EPA thanks USDA for the comments on the dietary assessment.  Dimethenamid was assessed with the version of Pesticides in Water Calculator (PWC) current at the time and the Agency would not expect changes in the overall exposure estimates or risk conclusions using the newer version of the model. As USDA noted, there were no dietary risks of concern noted in HED's dimethenamid risk assessment; therefore, EPA is not updating the assessment with additional refinements at this time. EPA may update the drinking water assessment in future actions, if warranted. The DWA has been posted to the docket. 

Comment: USDA also provided comments on EPA's dimethenamid ecological risk assessment.  USDA requested EPA consider adding additional characterization related to the RQs for mammals exposed to liquid formulations (using mean Kenaga residue values), include information on the percent of a mammal's diet that would need to be consumed to exceed the LOC, add characterization related to exposure from aerial applications of dimethenamid, and relate best practices for applying dimethenamid relate to the risk assessment findings.  In addition, USDA requested EPA consider using average application rates, instead of labeled maximum rates, in the risk assessment.  The comments also noted the "...incidents and water monitoring data indicate a low likelihood of harm to non-target organisms, and that existing label mitigations are protective."  

EPA Response: EPA thanks USDA for the comments and the additional information related to the ecological risk assessment. While some of USDA's suggestions related to how the calculated risks reflect typical use of dimethenamid/-p products, this additional characterization would not be reflected in updated RQs in the ecological risk assessment; however; this information was considered as part of the risk management process in the development of this PID.  For example, EPA continues to calculate RQs using maximum applications rates since labels allow use up to those maximum rates.  However, additional usage information helps add characterization on the how extensive and likely it is that there may be exceedances based on typical usage data.  While a low number of incidents and results from monitoring data can help inform regulatory decisions, it is not appropriate to only rely on those sources to predict risk.  EPA has identified a number of potential risks of concern for non-target organisms and has proposed mitigation to address those potential risks. 

Comment: USDA encourages EPA to consider a more comprehensive approach to MRL harmonization by evaluating not only existing U.S. tolerances, but also cases where Codex has established an MRL and EPA has no corresponding tolerance. For dimethenamid/-p, these cases include eggs, meat from mammals other than marine mammals, milk, poultry meat, and poultry edible offal (Codex Alimentarius, 2006). USDA encourages EPA to evaluate the potential for Codex-aligned tolerances for these commodities.

EPA Response: EPA thanks the USDA for its comments and will take them into consideration. Regarding the potential for additional harmonization with Codex, EPA attempts to harmonize existing US tolerances with Codex MRLs where feasible. However, harmonization is not possible in some cases due to a difference in tolerance expression (e.g., a difference in metabolites covered), a difference in commodity definition (e.g., livestock meat versus livestock fat), or a difference in use pattern (e.g., treatments in the field versus post-harvest treatments). Additionally, the Agency does not establish new tolerances in the registration review process other than those that might result from crop group updates. Any petition to establish a new tolerance should be sent to the Registration Division Product Manager for dimethenamid.

Comments Submitted by the NCC in Document ID: EPA-HQ-OPP-2015-0803-0023

Comment: The NCC provided comments related to the use and benefits of dimethenamid/-p in the cotton growing regions. The NCC surveyed agronomists and weed scientists who noted the importance of dimethenamid/-p in cotton production, particularly as related to resistance management and good residual activity. NCC also encouraged the Agency to revise the risk assessments to reflect the water model currently approved for regulatory use in the Office of Pesticide Programs.

EPA Response: EPA appreciates the NCC's input on the use and benefits of this herbicide in cotton production and has considered them in developing this for their comments. EPA acknowledges the many benefits associated with the use of dimethenamid/-p. The Agency also thanks NCC for its comments regarding impregnated fertilizer. At this time the risk assessment will not be updated, but these comments have been considered in the development of this PID.

As noted above, dimethenamid/-p was assessed with the version of PWC current at the time and would not expect changes in the overall exposure estimates or risk conclusions using the newer version of the model.

Comments Submitted by NAAA in Document ID: EPA-HQ-OPP-2015-0803-0021

Comment: NAAA stated the overall importance of aerial applications and the advantages of aerial applications over other forms of application. While NAAA supports the proposed spray drift mitigation language for aerial applications, NAAA described the need for clear label language regarding the specific altitude above which temperature inversions are not of concern. NAAA states it is currently collaborating with the USDA-ARS Aerial Application Technology Research Unit to conduct a literature review on the matter.    

EPA Response: EPA thanks NAAA for the comments and for their work with USDA-ARS to conduct a literature review.  The Agency will review any additional information submitted regarding the altitude of temperature inversions as it relates to pesticide applications.  The Agency will also consider revisions to the label language if supported by the information submitted.

USE AND USAGE

Dimethenamid/-p are Group 15 herbicides that control weed seedlings before they emerge. 
Registered agricultural use sites include dried beans, chickpeas, cotton, corn, fallow lands, garbanzo beans, garlic, hops, horseradish, leeks, lentils, onions, peanuts, potatoes, scallions, shallots, squash, sorghum, soybeans, sugar beets, and grass grown for seed. Dimethenamid-p is also used on major non‐agricultural use sites including landscape and grounds maintenance areas, tree plantations, turfgrass areas, golf courses, ornamental gardens, commercial ornamental production sites and grass grown for seed; dimethenamid is also registered for use on turfgrass. 
REGISTERED END-USE PRODUCTS include emulsifiable concentrates (EC), granules (G), and as a liquid impregnated onto dry bulk fertilizer formulations. Products can be applied using ground, aerial, backpack/handheld sprayers, and soil incorporation equipment, and liquid impregnated dry bulk fertilizer.

Agricultural Usage

Dimethenamid was first registered in the United States in 1993; dimethenamid-p was first registered in the United States in 1999. Because dimethenamid-p is more biologically active, the market has shifted from dimethenamid to dimethenamid-p over time, and dimethenamid-p is used at lower rates. All high acreage field crops (e.g., corn, soybean, etc.) for which dimethenamid was initially registered are now registered use sites for dimethenamid-p. In terms of total acres treated, dimethenamid-p appears to be slowly replacing dimethenamid in all surveyed use sites.[1] 

From 2014-2018, an annual average of 210,000 lbs dimethenamid were applied to about 270,000 acres of corn, dry beans/peas, sorghum, soybeans, and sweet corn.[1] Total acres treated accounts for multiple applications to a single acre. In the same period, an annual average of 6,000,000 lbs of dimethenamid-p were applied to about 11,700,000 acres of alfalfa, beans (snap/bush/
pole/green), corn, cotton, dry beans/peas, fallow, garlic, onions, peanuts, peas (fresh/green /sweet), potatoes, pumpkins, sorghum, soybeans, squash, sugar beets, and sweet corn.[1]

Dimethenamid has reported usage for corn, sorghum, soybeans, dry beans/peas, and corn. However, usage data indicate that less than 1% of these crops are treated with dimethenamid.[1] Dimethenamid-p has reported usage for onions, potatoes, sweet corn, garlic, dry beans/peas, sugar beets, corn, soybeans, and squash. Approximately 40% of the onion crop is treated with dimethenamid-p, while only 5% of the squash, soybean, and corn crops are treated with dimethenamid-p.[1] Potatoes, sweet corn, garlic, dry beans/peas, and sugar beets were between 10-20 PCT with dimethenamid-p.[1] High PCT values are associated with the active ingredient can indicate the use of the chemical is beneficial to the grower. Although the greatest number of pounds active ingredient applied and total acres treated were on soybeans and squash, a PCT of 5 suggests growers are not relying heavily on dimethenamid-p, but primarily use other active ingredients.

Non-agricultural Usage

Recent non-agricultural usage data does not show use of dimethenamid or dimethenamid-p. The most recent information available to the Agency dates from 2011-2013 and likely is not representative of current market trends.

SCIENTIFIC ASSESSMENTS

 Human Health Risks 

A summary of the Agency's human health risk assessment is presented below. The Agency used the most current science policies and risk assessment methodologies to prepare a risk assessment in support of the registration review of dimethenamid/-p.  For additional details on the human health and drinking water assessments for dimethenamid/-p, see the Dimethenamid/ Dimethenamid-p: Draft Human Health Risk Assessment for Registration Review, and other supporting documents, which are available in the public docket. 

Risk Summary and Characterization

Dietary (Food + Water) Risks

Both the acute and chronic dietary risk assessments are unrefined. They were based on tolerance-level residues, relied 2018 default processing factors, and assumed 100% crop treated. Estimated drinking water concentrations (EDWCs) used in the assessments are screening level upper-bound estimates based on the use parameters for turf that yield the highest potential exposures and were modeled with the total-residue method. 

Drinking water is the biggest contributor to dietary risk and modeled concentrations in groundwater were used for the assessment. As a conservative measure, the Agency determined that the residues of concern in drinking water are parent and the ethanesulfonic acid and oxanilic acid degradates (also referred to as the dimethenamid-ESA degradate and the dimethenamid-OA degradate, respectively).  There is little or no toxicity data available for the degradates and, although the degradates appear to be less toxic than the parent, they are included as residues of concern since they were identified as potentially significant degradates in the available fate data and found in greater abundance than the parent in some of the water monitoring studies.

For the acute assessment, dietary (food and drinking water) risks are below the level of concern (LOC) (<100% of the aPAD) at the 95th percentile of exposure for all population subgroups, while the chronic dietary risks are below the LOC (<100% of the aPAD) for all population subgroups. The population subgroup with the highest estimated acute and chronic dietary exposure is infants (<1 year of age) with an estimated risk at 95th percentile of exposure equivalent to 11% of the aPAD and a risk at 94% of the cPAD, respectively. Because the dietary (and aggregate) risks were not of concern, refinements to the assessment were not needed.

Residential Handler Risks

A quantitative residential handler assessment for dimethenamid/-p has not been conducted, as products labeled with residential use sites (EPA Reg. No. 7969-239, 7969-273, 7969-358) require that handlers wear baseline attire, chemical-resistant gloves, and protective eyewear, while EPA Reg No. 7969-239 also requires coveralls. Based on these requirements for PPE, the 
Agency has assumed that these products containing dimethenamid-p are not intended for homeowner use.

Residential Post-Application Risks

No residential post-application incidental oral (children 1 to <2 years old) margins of exposure
(MOEs) were identified as risks of concern. The Agency has not identified a dermal hazard at doses relevant to the risk assessment, and a quantitative residential post-application dermal exposure assessment was not conducted.

Aggregate Risks

Acute aggregate exposures to dimethenamid/-p are anticipated to occur from food and drinking water uses only. Because no acute dietary risks of concern were identified, there are no risks for acute aggregate exposure. Similarly, because no long-term non-dietary exposure is expected to occur with dimethenamid/-p, evaluation of chronic aggregate risk involved only dietary (food + drinking water) estimates. There were no risk concerns for chronic dietary exposure, and so there are no risk concerns for chronic aggregate exposure. Short-term aggregate risk estimates (food, water, and residential) were not of concern for children 1 to <2 years old, based on incidental oral exposure and background dietary (food + water) exposure' the resulting MOE is 330 (LOC = 100; with MOEs greater or equal to the LOC not a risk of concern).

Cumulative Risks

EPA has not made a common mechanism of toxicity to humans finding as to dimethenamid/-p and any other substance and it does not appear to produce a toxic metabolite produced by other substances. Therefore, EPA has not assumed that dimethenamid/-p has a common mechanism of toxicity with other substances for this assessment.

Non-Occupational Spray Drift Assessment

The Agency has determined that a quantitative risk assessment is not needed for non-occupational spray drift exposures. The currently registered maximum single application rate of dimethenamid/-p (for field crops) is 1.5 lb ai/A. A quantitative spray drift assessment for dimethenamid/dimethenamid-P is not needed because this maximum application rate multiplied by the adjustment factor for drift of 0.26 is less than the maximum direct spray residential turf application rate (also 1.5 lb ai/A). There are no risks of concern for residential post-application exposures to dimethenamid/-p, and the concentration of drift residues deposited on residential sites would be lower than those associated with direct applications to turf. Thus, a quantitative assessment is not needed and there are no risks of concern for non-occupational drift exposures.

Occupational Handler Risks 

Occupational handler inhalation exposure and risk estimates were calculated for the registered
uses of dimethenamid/-p. Most risk estimates were not of concern for handlers wearing label-required clothing and PPE (i.e., no respirator). Four occupational handler scenarios resulted in MOEs below the LOC of 1,000, representing potential risks of concern:

   1. Mixer/Loader/Applicators applying a liquid formulation with a mechanically pressurized handgun as a drench or soil- and ground-directed application to the following use sites:
 Nursery (ornamentals, vegetables, trees, container stock), MOE=40 (at baseline); 400 when a PF10 respirator is added
 Hops (represented by the orchard/vineyard scenario), MOE = 610 (at baseline); 6100 with a PF10 respirator is added
 Field crop, typical, MOE = 610 (at baseline); 6100 with a PF10 respirator is added
   2. Mixer/Loader; applying a liquid formulation for commercial impregnation of dry bulk fertilizer, MOE = 670 (with engineering controls applied)

Occupational Post-Application Risks 

Because a dermal hazard not being identified, a quantitative dermal occupational post-application exposure assessment was not conducted. The Agency may revisit the need for a quantitative occupational post-application inhalation exposure assessment for dimethenamid/-p, if new policies or procedures are put into place that necessitate a change.

Human Incidents and Epidemiology

Both the OPP Incident Data System (IDS) and the Centers for Disease Control and Prevention/National Institute for Occupational Safety and Health (CDC/NIOSH) Sentinel Event Notification System for Occupational Risk-Pesticides (SENSOR) databases were consulted for pesticide incident data on the active ingredients dimethenamid/-p.

From January 1, 2010 to April 13, 2020, there were no dimethenamid/-p incidents reported to either the Main or Aggregate IDS. However, there was one moderate severity incident reported for dimethenamid/-p in the Main IDS. The incident involved a 30-year-old female who was sprayed with a product containing dimethenamid (Reg. No. 7969-156) while out running, after which she experienced an asthma attack. The Aggregate IDS also records of eight minor incidents involving active ingredient dimethenamid/-p.

A query of SENSOR-Pesticides from 2012-2015 was conducted and no cases involving dimethenamid or dimethenamid-p were identified.
  
Dimethenamid/-p is part of the Agricultural Health Study (AHS), a long-term epidemiological study. As of May 2020, three AHS publications investigated the association between dimethenamid/-p exposure and health effects. These studies are summarized below. For additional information regarding the AHS study, please see the Dimethenamid and Dimethenamid-p: Tier I Update Review of Human Incidents and Epidemiology for Draft Risk Assessment, which can be found in the public docket.

One study examined the association between dimethenamid/-p exposure and prostate cancer among male pesticide applicators. Two other studies examined the association between dimethenamid/-p exposure and of sleep apnea and respiratory effects among male pesticide applicators. At this time, the Agency has determined that there is no epidemiological evidence to suggest a clear associative or causal relationship between dimethenamid exposure and prostate cancer, and insufficient epidemiological evidence for sleep apnea and these respiratory effects.

The Agency will continue to monitor the incident and epidemiology information, and additional analyses will be conducted if that information indicates a concern.

Tolerances

The Agency has determined that the tolerance expressions for dimethenamid/-p, as currently captured in 40 CFR §180.464, are not in accordance with the Agency's Interim Guidance on Tolerance Expressions. For 40 CFR §180.464(a), EPA is recommending that the tolerance expression be changed to read: 

      Tolerances are established for residues of dimethenamid (2-chloro-N-(2,4-dimethyl-
      3-thienyl)-N-(2-methoxy-1-methylethyl)acetamide) or dimethenamid-P (2-chloro-N-(2,4-
      dimethyl-3-thienyl)-N-[(1 S)-2-methoxy-1-methylethyl]acetamide), including its metabolites and degradates, in or on the commodities in the table below. Compliance with the tolerance levels specified below is to be determined by measuring only dimethenamid or dimethenamid-P as the sum of its R- and S-isomers in or on the commodity.

For 40 CFR §180.464(c), the Agency is recommending that the tolerance expression be changed to read: 

      Tolerances with regional registrations. Tolerances are established for residues of dimethenamid (2-chloro-N-(2,4-dimethyl-3-thienyl)-N-(2-methoxy-1-methylethyl)acetamide) or dimethenamid-P (2-chloro-N-(2,4-dimethyl-3-thienyl)-N-[(IS)-2-methoxy-1-methylethyl]acetamide), including its metabolites and degradates, in or on the commodities listed in the table below. Compliance with the tolerance levels specified below is to be determined by measuring only dimethenamid or dimethenamid-P as the sum of its R- and S-isomers in or on the commodity.

No change to the established tolerance definition (parent only) is recommended.
The Agency anticipates the following changes to the tolerances for dimethenamid/-p. The Agency intends to undertake these tolerance actions pursuant to its Federal Food, Drug Cosmetic Act (FFDCA) authority. Recommendations for dimethenamid/-p tolerances are presented below in Table 1.

Table 1: Summary of Anticipated Tolerance Actions
Table 1 Tolerance Summary for Dimethenamid and Dimethenamid-p. (40 CFR §180.464(a)).
                                  Commodity/
                         Correct Commodity Definition
                          EstablishedTolerance (ppm)
                          Recommended Tolerance (ppm)
                                   Comments
                              40 CFR §180.464(a)
Beet, sugar, dried pulp
0.01
Remove
Residues are covered by the tolerance established for the raw agricultural commodity, beet, sugar, roots (0.01 ppm).
Beet, sugar, molasses
0.01
Remove

Cassava, bitter, leaves
--
0.01
Tolerances in/on these commodities are required due to registered use on crop subgroup 1C. The tolerance in/on beet, garden, tops or beet, sugar, tops[1] (0.01 ppm) applies.
Cassava, sweet, leaves
--
0.01

Lentil, dry, seed
--
0.01
A tolerance in/on this commodity is required due to registered use on lentils. No data for pea are available. The tolerance in/on bean, dry, seed (0.01 ppm) applies.
Onion, Welsh
0.01
Remove
The established tolerance in/on onion, green (0.01 ppm) also applies to Welsh onion.
Sweet potato, leaves
--
0.01
Tolerances in/on these commodities are required due to registered use on crop subgroup 1C. The tolerance in/on beet, garden, tops or beet, sugar, tops[1] (0.01 ppm) applies.
Tanier, leaves
--
0.01

Taro, leaves
--
0.01

Turnip, greens
0.1
Remove
The only registered use of dimethenamid/dimethenamid-P on turnip (EPA Reg. No. 7969-156) is clearly for the root crop, turnip. 
Yam, true, leaves
--
0.01
A tolerance in/on this commodity is required due to registered use on crop subgroup 1C. The tolerance in/on beet, garden, tops or beet, sugar, tops (0.01 ppm) applies.    
1. ChemSAC has agreed that the representative crops for Crop Group 2 are garden beet leaves or sugar beet leaves. See Recommendation for Amending Crop Group 2 Leaves of Root and Tuber Vegetable to Approve Its Members, Representative Commodities, and Associated Commodity Definitions dated 09/15/2017. Tolerances for residues of dimethenamid/dimethenamid-P in/on garden beet tops and sugar beet tops are both 0.01 ppm.

International Harmonization

Codex and Canadian MRLs for residues of the parent have been established for some of the same commodities that have tolerances in the U.S.  Mexico adopts U.S. tolerances and/or Codex MRLs for its export purposes. Further harmonization with Canadian MRLs is not achievable without the concomitant loss of harmonization with Codex MRLs.

Human Health Data Needs

The toxicity database is considered complete for both dimethenamid and dimethenamid-p, with the exception of a subchronic inhalation study.  The Agency, based on a Weight of Evidence (WOE) approach that considered all available hazard and exposure information, previously determined that the requirement for a subchronic inhalation study could be waived (M. King, 06/19/2014, TXR 0056993).  Subsequently, when occupational use scenarios were updated, HASPOC recommended that the subchronic inhalation toxicity study is required at this time for dimethenamid/-p (J. Leonard, 6/11/20). Until an appropriate subchronic inhalation study is provided, an additional database uncertainty factor (UFDB) of 10X arising from the lack of this study is needed, resulting in a LOC of 1000 for inhalation exposures to occupational handlers.  

Ecological Risks

A summary of the Agency's ecological risk assessment is presented below. The Agency used the most current science policies and risk assessment methodologies to prepare a risk assessment in support of the registration review of dimethenamid/-p. For additional details on the ecological assessment for dimethenamid/-p, see the Draft Ecological Risk Assessment for Dimethenamid and Dimethenamid-p, which is available in the public docket.

EPA is currently working with its federal partners and other stakeholders to implement an interim approach for assessing potential risk to listed species and their designated critical habitats. Once the scientific methods necessary to complete risk assessments for listed species and their designated critical habitats have been fully implemented, the Agency will complete its endangered species assessment for dimethenamid/-p. See Appendix C for more details. As such, potential risks for non-listed species only are described below. 

 Risk Summary and Characterization

Terrestrial Risks 

Terrestrial wildlife exposure estimates were calculated for birds and mammals for the dietary exposure pathway. Dimethenamid/‐p is applied via aerial and ground application methods for liquids and via ground spreader for the granular uses. Therefore, potential dietary exposure for terrestrial wildlife is based on consumption of residues on food items following spray (foliar) applications, and from possible dietary ingestion of the granular formulation. Risk to mammals and birds from the foliar and granular uses was assessed at the maximum application rates. The highest exposure to birds and mammals results from the application scenario of 1.5 lb ai/A applied two times at a 35‐day interval (some turf uses).

Mammals 

For mammals, dimethenamid/‐p is classified as "moderately toxic" to "slightly toxic. In a mammalian reproduction study with the rat, the NOAEC is 500 mg a.i./kg diet based on body weight effects at 2000 mg a.i./kg diet.

Based on acute oral toxicity, the foliar acute risk quotients (RQs) ranged from <0.01‐0.49, thus, there are no LOC exceedances for mammals. For sublethal/chronic risk, the dose-based RQs ranged from 0.03‐9.4.

Birds, Reptiles, and Terrestrial-Phase Amphibians 

Dimethenamid/‐p is classified as "slightly toxic" to birds on an acute oral basis. On a subacute dietary basis, data are available for the mallard duck, bobwhite quail, and a passerine species [Canary (Serinus canaria)] and for all three species tested, dimethenamid‐p is classified as "practically non‐toxic" with a non‐definitive endpoint (e.g., LC50 >5000 mg a.i./kg‐diet).

Foliar acute RQs ranged from <0.01‐0.80 (exceeding the LOC of 0.5). The RQ of 0.8 is for small birds feeding on short grass, which is not a typical dietary item for small birds. With mean Kenaga EECs, there are no acute LOC exceedances for birds.

While there is an LOC exceedance for small birds consuming granules with an assumption of a 1 mg granule weight, a 20 gram bird would need to consume ~1000 granules to reach the LOC. While birds do consume grit, consumption of 1000 granules is beyond the expected intake. Risk to birds and mammals from the granular use is considered low.

Chronic RQs ranged from 0.09‐1.5 (again, the greatest exceedances of the LOC were estimated for short grass dietary items). The endpoint is based on a 6.6% body weight reduction at a dose of 900 mg ai/kg diet. At the LOAEC, there were no chronic RQ exceedances.

Terrestrial Invertebrates (honey bees) 
 
Dimethenamid/-p is a selective herbicide with limited systemicity, registered for pre-emergent/post-emergent control of annual grasses, weeds, and sedges in various crops. Leading uses include corn, sorghum, soybeans and sweet corn.  While none of these crops require bee pollination, all are attractive sources of pollen for bees. Pumpkins and squash are registered crops (in OR and WA only) that are bee-attractive for pollen and nectar and require managed pollinator services. Pollinators may be exposed via direct deposition or off-field via drift for applications made during bloom or via translocation of residues to pollen and nectar after bloom. Pollen and nectar residue data are not available for dimethenamid/‐p, but, the Tier 1 battery of acute and chronic toxicity tests on adult and larval bees is complete.

On-field Risks
  
On the basis of acute contact exposure to adult honey bees, RQs range from 0.028‐ 0.043 for application rates of 1 (rounded up from 0.98) and 1.5 lb a.i./A, respectively. Based on this analysis, there are no LOC exceedances for the highest use rates, thus, contact risk to adult bees is low. 

Chronic RQs for larval bees (range: 2.2  -  3.2) exceed the LOC of 1.0. EECs also exceed the chronic larval LOAEL, which is based on a 50% reduction in survival/emergence.  Chronic RQs for adult honey bees were not calculated due to the non-definitive endpoint (the LOAEL of 2.5 ug ai/bee/day was based on a 15% reduction in food consumption at the lowest dose tested). EECs were 13 -20 times higher than the LOAEL, indicating potential risk to adult bees. A refinement to factor a solvent effect is in progress for this study but exceedances will remain. There are no incident reports involving bees associated with the use of dimethenamid-p. 

The application timing for dimethenamid/-p is described as pre‐ and post‐emergence, with the initial application in the early crop growth stages. With a variety of pollinator attractive
uses, and sensitivity to both adult and larval stage bees, submission of reliable residue data
(e.g., from foliar residue, magnitude of residue, or rotational crop studies) may provide useful
estimates for refinement of risk.

Off-field Risks

In addition to foraging on treated fields, bees may also forage in areas adjacent to treated fields. AgDrift model estimates for risk extend 125‐180 feet from treated fields for aerial applications and up to 50 feet for ground applications. Effects distances are greatest for higher boom heights and smaller droplet sizes.

Terrestrial Plants 

As dimethenamid/-p is an herbicide, risks to non-target plants from exposure to dimethenamid/-p are not unexpected. The risk is greatest for terrestrial plants in semi-aquatic areas vulnerable to runoff. Based on the 90th percentile EEC assumptions for spray drift at the 0.98 lb a.i./A rate, modeling predicted LOC exceedances for plants inhabiting dry areas and ponds/wetlands at distances from the edge of the field up to 790‐1000 ft for aerial application with medium/coarse sprays and 420‐680 ft with coarse/very coarse sprays. For low‐boom ground application and medium/coarse sprays the effects distance is 68‐118 ft; for high-boom and medium/coarse sprays, it is 120‐200 ft.

Plant incidents are discussed in Section III.B.2 below.

Aquatic Risks

Freshwater and Estuarine/Marine Fish and Aquatic-Phase Amphibians 

On an acute and chronic exposure basis, there are no LOC exceedances for aquatic vertebrates
(acute RQs <0.01; chronic RQs 0.08‐0.20).  Acute risks to freshwater and estuarine/marine fish, and chronic risks to estuarine/marine fish are low. Chronic RQs for estuarine/marine fish were not calculated as chronic toxicity data for these taxa were waived on the basis of low chronic toxicity in freshwater species. 

Aquatic Invertebrates 

On an acute and chronic exposure basis, there are no LOC exceedances (acute RQs <0.01‐0.01;
chronic RQs 0.01‐0.02).  Acute risk to freshwater and estuarine/marine invertebrates is low, as are chronic risks to freshwater species. Chronic RQs for estuarine/marine invertebrates were not calculated as chronic toxicity data for these taxa were waived on the basis of low chronic toxicity in freshwater species.

Aquatic Vascular and Non-Vascular Plants 

Potential risks of concern to aquatic vascular and non‐vascular plants were identified. RQs range from 1.3‐3.6 and 0.86‐2.3 for vascular and non‐vascular plants, respectively (LOC=1).

Ecological Incidents

The Incident Data System (IDS) provides information on the available ecological pesticide
incidents, including those that have been aggregately reported to the EPA. The incident
database was queried on November 7, 2019. All reported incidents were to plants and there have been no new incidents reported since the publication of the PWP.

Plant incidents were reported for a number of different use sites. For dimethenamid, there were 19 incidents reported between 1997 and 2001.There were eight incidents reported for dimethenamid-p between 2001 and 2014. All 27 incidents were considered to be of "possible" certainty. 

The Agency will continue to monitor ecological incident information as it is reported to the Agency. 

Ecological and Environmental Fate Data Needs

The environmental fate database is complete. Given risks concerns at the Tier I level, the following data would be helpful in order to conduct a complete pollinator risk assessment. These data are described under the Guidance for Assessing Pesticide Risks to Bees.

       Non‐guideline (Tier II): Semi‐field testing for pollinators (tunnel or colony feeding studies)
       Non‐guideline (Tier II): Field trial of residues in pollen and nectar
       OCSPP 850.3040 (Tier III): Field testing for pollinators (pending risk conclusions from the Agency's analysis of Tier II studies)

 SUMMARY OF BENEFITS

Dimethenamid-p can be applied both before and after crop emergence, allowing growers a longer application window throughout the growing season. Fertilizer impregnation with dimethenamid/-p allows growers to complete herbicide and fertilizer applications simultaneously in a single pass through the field. Dimethenamid/-p controls major agricultural and non-agricultural broadleaf and grassy weeds such as redroot pigweed, waterhemp, and foxtails. Dimethenamid-p is reported to provide up to 12 weeks of residual control in field ornamentals, landscape, and nurseries, and 6-8 weeks of control in container plants. 

For corn production, several herbicides are available to control weeds before they emerge. This is not the case for hops, where dimethenamid-p, pendimethalin, and flumioxazin are the only residual herbicides that can be applied during the growing season (non-dormant season). Though growers have several herbicide options for general weed control in nurseries, dimethenamid-p is the only herbicide that can reportedly control woodsorrel, marsh parsley, and Kyllinga.  For corn, hops, and nursery-grown ornamentals, dimethenamid-p is a valuable tool in herbicide rotational programs for resistance management.  

For additional information please see Dimethenamid and Dimethenamid-P: Use, Usage and Benefits Information Including Impacts from Mitigation, which is available in the public docket.

IV.	PROPOSED INTERIM REGISTRATION REVIEW DECISION

    A.	Proposed Risk Mitigation and Regulatory Rationale

The Agency has reviewed the uses, risks, and benefits of dimethenamid/-p. As discussed in Section III of this document, EPA identified potential risks of concern for some occupational handlers, which, as detailed below, can be mitigated with specific label changes involving PPE, application method, and application volume and rate. The Agency has also identified potential risks of concern for wildlife, which can be addressed via spray drift management and advisory labeling. The registrant of technical grade dimethenamid/-p, BASF, has agreed to the mitigation proposed in this PID. 

       1.	Occupational Handlers
      
The Agency is proposing mitigation measures for several occupational handler scenarios. Scenarios with MOEs less than the LOC of 1000 (representing potential risks of concern) reflecting PPE on current dimethenamid/-p labels (i.e., no respirators) are:
 Mixer/loader/applicators of liquid formulations using mechanically pressurized handguns for drench and soil- or ground-directed applications on the sites listed below:
          Hops (represented by the orchards/vineyard scenario) MOE = 610
          Nursery (ornamentals, vegetables, trees, container stock), MOE=40 
          Field crop, typical, MOE = 610
         and
       Mixer/loaders of liquid formulations used for impregnation of dry bulk fertilizers in commercial facilities, MOE = 670 (with the use of closed systems)
      
a. 	Respirators--Applications to Hops and Nursery Sites 

To mitigate potential inhalation risks to occupational handlers applying dimethenamid/-p in the field, the Agency is proposing the use of PF-10 respirators (in addition to current PPE requirements on the label) for mixer/loader/applicators of liquid formulations using mechanically pressurized handguns for drench, and soil- and ground directed applications for hops and nurseries. The MOEs shown here are based on the use of these respirators.  The LOC is 1000.
 Hops (represented by the orchards/vineyard scenario) MOE = 6100
 Nurseries, MOE = 400 

The risks from use of dimethenamid/-p on hops are no longer of concern with the addition of the PF-10 respirator.  For the nursery scenario, an additional measure is needed to address the risks of concern, as described in Section b below.  

Mixer/loader/applicators typically do not use mechanically pressurized handguns to apply pesticides to field crops, so the Agency is proposing an alternative approach to risk management, as described below. The risk management proposal for the mixer/loader impregnated fertilizer scenario as discussed in Section c below. 

EPA has required fit testing, training, and medical evaluations for all handlers who are required to wear respirators and whose work falls within the scope of the WPS.  If a dimethenamid/-p handler currently does not have a respirator, an additional cost will be incurred by the handler or the handler's employer, which includes the cost of the respirator plus, for WPS-covered products, the cost for a respirator fit test, training, and medical exam.  

Respirator costs are extremely variable depending upon the protection level desired, disposability, comfort, and the kinds of vapors and particulates being filtered. Based on available information that EPA has, the cost of the respirators (whether disposable or reusable) is relatively minor in comparison to the fit-test requirement under the Worker Protection Standard.  The Agency expects that the average cost of a particulate filtering facepiece respirator is lower than the average cost of an elastomeric half mask respirator. The cost of a respirator fit test, training and medical exam was estimated to about $180 annually.  However, if a dimethenamid/-p handler typically uses other chemicals requiring a respirator in the production system or as part of the business, additional fit testing is not needed. The handler or employer may only incur the cost of purchasing filters for the respirator on a more frequent basis. Respirator fit tests are currently required by the Occupational Safety and Health Administration (OSHA) for other occupational settings to ensure proper protection. 

EPA acknowledges that requiring a respirator and the associated fit testing, training, and medical evaluation places a burden on handlers or employers. However, the proper fit and use of respirators is essential to accomplish the protections respirators are intended to provide. In estimating the inhalation risks, and the risk reduction associated with different respirators, EPA's human health risk assessments assume National Institute for Occupational Safety and Health (NIOSH) protection factors (i.e., respirators are used according to OSHA's standards). If the respirator does not fit properly, use of dimethenamid/-p may cause unreasonable adverse effects on the pesticide handler. 

b. 	Spray Volume for Nursery Applications

As noted above, for mixer/loader/applicators treating nursery sites with liquid formulations, using mechanically-pressurized handguns for drench or soil-/ground directed applications wearing PF-10 respirators, the estimated risks would still fall below the LOC (MOE = 400, relative to the LOC of 1000, representing a potential risk of concern).  The Agency is proposing that, in addition to the respirators, labels require use of an increased spray volume from 20 Gallons Per Acre (GPA) to 30 GPA for this scenario. 

Increasing the minimum spray volume would have no effect on the application rate of dimethenamid because applicators would still apply the required amount of dimethenamid/-p, albeit in a larger spray volume. However, the spray will be more dilute, so handlers will be exposed to less of the pesticide in a day's work. Increasing the spray volume could necessitate that the spray tank be refilled more often. In addition, dependent on field acreage, applicators may need to dedicate more days per year to spray all acres. For instance, if growers typically sprayed 1000 acres per day, the increased volume per acre would reduce the number of treated acres to 666 acres per day, requiring an additional day to spray the remaining acres. 

If growers cannot increase the application volumes as proposed, they would have to consider using another herbicide or combination of herbicides to control the same weeds as dimethenamid/-p alone, which could result in increased costs or reduced control of target weeds. 
            
       Prohibition of Application Equipment for Use on Field Crops

The Agency is proposing to prohibit the use of mechanically pressurized handguns for drench, soil- and ground-directed applications to field crops. In discussions with the registrant, it was brought to our attention that dimethenamid/-p is generally not used in this way, so the registrant has agreed to the prohibition. This proposed mitigation measure is likely to have minimal impacts to growers. 

d.  	Fertilizer Impregnation
       
Risks to mixer/loaders conducting commercial impregnation of dimethenamid/-p formulated end-use products onto dry bulk fertilizer using closed mixing/loading systems are represented by an MOE of 670. The assessment is based on a processing rate of 960 tons of fertilizer per 8-hour day (information supplied by a registrant for alachlor). In most cases, these handlers will not be applying dimethenamid/-p to fertilizer every day for more than a one-month time frame; however, there may be large agribusinesses and/or commercial applicators who may do so over a period of weeks. Thus, risks were assessed for short- and intermediate- term exposures.

Reducing these risks can be achieved using several different approaches to limit the amount of active ingredient handled by a mixer/loader per day.  

At present, the labels of dimethenamid/-p products registered for fertilizer impregnation require a minimum fertilizer application rate of 200 lbs./A. In order to address these risks of concern, the Agency is proposing that the minimum amount of impregnated fertilizer applied to the field per be increased to 300 pounds per acre. The maximum rate of dimethenamid/-p applied to the field (1.5 lb.s a.i./A) would not change, but the amount of dimethenamid-p per ton of fertilizer would be lower, and the exposure to mixers and loaders at commercial facilities would be reduced below the Agency's level of concern.  The Agency is also proposing that the maximum amount of impregnated fertilizer be increased to 1000 lbs/A, consistent with typical agronomic practices -- if fertilizer rates are too low, application may not be uniform across the field. The higher fertilizer application rate can reduce exposures for the mixer/loaders involved in fertilizer impregnation even further.

If, for some reason, growers cannot increase the minimum fertilizer application rate, they would have to consider using another herbicide or combination of herbicides in the fertilizer, or apply dimethenamid/-p separately from non-impregnated fertilizer, potentially resulting in increased grower costs. 

    B. Label Cleanup 

The Agency is proposing an update to labels to current standards for certain PPE and advisory statements, and to specify that lentils be included as a use site separate from dry beans. 

The Agency is proposing that glove statements be made consistent with Chapter 10 of the Label Review Manual. In particular, the Agency is proposing the removal of reference to specific categories in EPA's chemical-resistance category selection chart and requiring that labels specify the appropriate glove types to use. For example, the chemical-resistant glove statements in the label should remove "such as" language and not state the solvent category, but rather add all acceptable glove types that provide high-level chemical resistance for the solvent category as mentioned in Table 3 of Chapter 10 of the Label Review Manual. This minor clarification does not fundamentally change the personal protective equipment that workers are currently required to use.

EPA is proposing to update the ground and surface water advisories that are currently on the label, and to add an advisory statement about cleaning up spilled granules. As advisories, the proposed changes should not result in economic impacts for growers.

Additionally, the Agency is proposing that lentils be listed as a separate crop on labels that mention them, as they are not considered by the Agency to fall under the definition of "dry beans". See Appendix B for additional details. As advisories, the proposed changes should not result in economic impacts for growers.

Other elements of label clarification are discussed in this section, with required labeling detailed in Appendix B.

       1.  Non-Target Organism Advisory Statement

The Agency is proposing the addition of a non-target organism advisory to dimethenamid/-p product labels. The protection of pollinating organisms is a priority for the Agency. Dimethenamid/-p may negatively impact forage and habitat of pollinators and other non-target organisms. It is the Agency's goal to reduce spray drift whenever possible and to educate growers on the potential for indirect effects on the forage and habitat of pollinators and other non-target organisms. The proposed non-target organism advisory language addresses these concerns.

 Herbicide Resistance Management 

On August 24, 2017, EPA finalized a Pesticide Registration Notice (PRN) on herbicide resistance management.  Consistent with the Notice, EPA is proposing the implementation of herbicide resistance measures for existing chemicals during registration review, and for new chemicals and new uses at the time of registration. In registration review, herbicide resistance elements will be included in every herbicide PID. 

The development and spread of herbicide resistant weeds in agriculture is a widespread problem that has the potential to fundamentally change production practices in U.S. agriculture. While herbicide resistant weeds have been known since the 1950s, the number of species and their geographical extent, has been increasing rapidly. Currently there are over 250 weed species worldwide with confirmed herbicide resistance. In the United States, there are over 155 weed species with confirmed resistance to one or more herbicides.

Management of herbicide resistant weeds, both in mitigating established herbicide resistant weeds and in slowing or preventing the development of new herbicide resistant weeds, is a complex problem without a simple solution. Coordinated efforts of growers, agricultural extension, academic researcher, scientific societies, pesticide registrants, and state and federal agencies are required to address this problem.

EPA is requiring measures for the pesticide registrants to provide growers and users with detailed information and recommendations to slow the development and spread of herbicide resistant weeds. This is part of a more holistic, proactive approach recommended by crop consultants, commodity organizations, professional/scientific societies, researchers, and the registrants themselves. 

Spray Drift Management 

The Agency is proposing label changes to reduce off-target spray drift and establish a baseline level of protection against spray drift that is consistent across all dimethenamid/-p products. Reducing spray drift will reduce the extent of environmental exposure and risk to non-target plants and animals. Although the Agency is not making a complete endangered species finding at this time, these label changes are expected to reduce the extent of exposure and may reduce risk to listed species whose range and/or critical habitat co-occur with the use of dimethenamid/-p.  

The Agency is proposing the following spray drift mitigation language to be included on all dimethenamid/-p product labels for products applied by liquid spray application. The proposed spray drift language is intended to be mandatory, enforceable statements and supersede any existing language already on product labels (either advisory or mandatory) covering the same topics. The Agency is also providing recommendations which allow dimethenamid/-p registrants to standardize all advisory language on dimethenamid/-p product labels. Registrants must ensure that any existing advisory language left on labels does not contradict or modify the new mandatory spray drift statements proposed in this PID, once effective.

 For ground boom applications, apply with the release height no more than 4 feet above the ground or crop canopy.
 For aerial applications, do not apply when wind speeds exceed 15 mph at the application site. If the windspeed is greater than 10 mph, the boom length must be 65% or less of the wingspan for fixed wing aircraft and 75% or less of the rotor diameter for helicopters. Otherwise, the boom length must be 75% or less of the wingspan for fixed-wing aircraft and 90% or less of the rotor diameter for helicopters.
 For aerial applications, the release height must be no higher than 10 feet from the top of the crop canopy or ground, unless a greater application height is required for pilot safety.
 For ground applications, do not apply when wind speeds exceed 15 miles per hour at the application site.
 Applicators are to select a nozzle and pressure combination that delivers a medium or coarser droplet size (ASABE S572 for ground applications and ASABE S641 for aerial applications).

In addition to including the spray drift restrictions on dimethenamid/-p labels, all references to volumetric mean diameter (VMD) information for spray droplets are to be removed from all dimethenamid/-p labels where such information currently appears. The new language above, which cites ASABE S572 for groundboom equipment and ASABE S641 for aerial equipment, eliminates the need for VMD information.

The Agency has determined that a maximum release height of 4 feet allows adequate coverage for the majority of nozzles. Therefore, EPA does not anticipate any negative impacts to growers from the requirement.

For aerial applications, allowing application at a maximum 15 mph windspeed will provide growers with greater flexibility to make applications in a timely manner.  A release height of 10 feet is a standard application practice and no impacts are anticipated. For ground applications, allowing application at a maximum 15 mph windspeed will provide growers with greater flexibility to make applications in a timely manner.

The Agency is proposing a restriction on droplet size, because coarser droplets have been demonstrated to decrease spray drift, and therefore, reduce potential risks to non-target species. Because chemical-specific data for the performance of droplet sizes is limited, EPA was not able to evaluate the effects of medium or coarser droplet sizes (as defined by ASABE S572 for groundboom application equipment and ASABE S641 for aerial application equipment) specifically for dimethenamid/-p. However, dimethenamid/-p are herbicides that are applied directly to the soil prior to weed emergence and work by inhibiting weed seedling growth. To be effective, these herbicides require soil incorporation to ensure contact with the weed seedlings. Soil incorporation will facilitate the chemicals' homogenous spread throughout the application site, and negate the need for smaller droplet size. For this reason, a medium or coarser droplet size should have little to no effect on the efficacy of dimethenamid or dimethenamid-p.

Tolerance Actions 

The Agency is anticipating changes to some of the tolerances as discussed in Section III.A.3 and will use its FFDCA rulemaking authority to make the needed changes to the tolerances.

Proposed Interim Registration Review Decision 

In accordance with 40 CFR §§ 155.56 and 155.58, the Agency is issuing this PID. Except for the Endocrine Disruptor Screening Program (EDSP) and the Endangered Species Act (ESA) components of this case, the Agency has made the following proposed interim decision: (1) no additional data are required at this time; and (2) EPA proposes that dimethenamid/-p does not meet the FIFRA registration standard without the changes to the affected registrations and their labeling described in Section IV. A and Appendices A and B. 

In this PID, the Agency is not making any human health or environmental safety findings associated with the EDSP screening of dimethenamid/-p. Similarly, the Agency is not making a complete endangered species finding for dimethenamid/-p. Although the Agency is not making a complete endangered species finding at this time, EPA expects that the proposed mitigation will reduce the extent of environmental exposure and may reduce risk to listed species whose range and/or critical habitat co-occur with the use of dimethenamid/-p. The Agency intends to complete a listed species assessment and any necessary Endangered Species Act (ESA) Section 7 consultation with the services, and an EDSP FFDCA Section 408(p) determination, before issuing a final registration review decision for forchlorfenuron. For more information, see Appendices C and D.

Data Requirements

The Agency does not anticipate calling-in additional data for registration review of dimethenamid/-p at this time. All data requirements from the registration review DCI have been satisfied with the exception of the Tier II and III honeybee data. EPA has determined that these data are needed for dimethenamid/-p, based on potential risk concerns identified in the Agency's review of the Tier I honey bee studies.

NEXT STEPS AND TIMELINE 

       A.	Proposed Interim Registration Review Decision

A Federal Register Notice will announce the availability of this PID for dimethenamid/-p and will allow a 60-day comment period. If there are no significant comments or additional information submitted to the docket during the comment period that leads the Agency to change its proposed interim decision, EPA may issue an interim registration review decision for dimethenamid/-p. However, a final decision for dimethenamid/-p may be issued without the Agency having previously issued an interim decision. A final decision on the dimethenamid/-p registration review case will occur after: (1) an EDSP FFDCA § 408(p) determination, and (2) an endangered species determination under the ESA and any needed § 7 consultation with the Services.

       B.	Implementation of Mitigation Measures 

Once the Interim Registration Review Decision is issued, the dimethenamid/-p registrants must submit amended labels that include the label changes described in Appendices A and B. The revised labels and requests for amendment of registrations must be submitted to the Agency for review within 60 days following issuance of the Interim Registration Review Decision in the docket.
   

Appendix A:  Summary of Proposed Actions for Dimethenamid/-p

                            Affected Population(s)

                              Source of Exposure
                               Route of Exposure
                             Duration of Exposure
                         Potential Risk(s) of Concern
                               Proposed Actions
Occupational Handlers (mixer/loader/applicator; mixer/loader)

Particulates/
droplets in the air
Inhalation
Short- and intermediate-term
Liver effects
-Require use of PF10 respirator
-Increase the min-max range of fertilizer lbs per acre
-Increase application volume
-Prohibit use of mechanically pressurized handguns on typical field crops
Terrestrial vertebrates
Residues on food items, ingestion of granules
Ingestion
Acute and chronic
Mortality
Weight effects
Drift management
Terrestrial invertebrates
Residues in food sources
Ingestion
Acute and chronic
Reduced food consumption
Drift management
Non-target organism advisory
Terrestrial Plants
Runoff and drift
Uptake
                                      --
Decreased growth 
Drift management
Aquatic Plants
Runoff and drift
Uptake
                                      --
Effects on cell density and frond biomass
Drift management
Appendix B:  Proposed Labeling Changes for Dimethenamid/-p Products

                                  Description
             Proposed Label Language for Dimethenamid/-p Products
                              Placement on Label
                               End-Use Products
--------------------------------------------------------------------------------
Mechanism of Action 
Note to registrant:
 --------------------------------------------------------------------------------
   Include the name of the ACTIVE INGREDIENT in the first column (choose one)
 --------------------------------------------------------------------------------
   Include the word "GROUP" in the second column
 --------------------------------------------------------------------------------
   Include the MECHANISM OF ACTION CODE in the third column (for Herbicides this is the Site of Action)
 --------------------------------------------------------------------------------
   Include the type of pesticide (i.e., HERBICIDE) in the fourth column. 
                                       
--------------------------------------------------------------------------------
DIMETHENAMID 
--------------------------------------------------------------------------------
or
--------------------------------------------------------------------------------
DIMETHENAMID-P
--------------------------------------------------------------------------------
GROUP
--------------------------------------------------------------------------------
15
--------------------------------------------------------------------------------
HERBICIDE
                                       
Front Panel, upper right quadrant.
All text should be black, bold face and all caps on a white background, except the mode of action code, which should be white, bold face and all caps on a black background; all text and columns should be surrounded by a black rectangle.
        Updated Gloves Statement -- if gloves are required by the label
                                       
Note to registrant:

Update the gloves statements to be consistent with Chapter 10 of the Label Review Manual.  In particular, remove reference to specific categories in EPA's chemical-resistance category selection chart and list the appropriate chemical-resistant glove types to use. 


In the Personal Protective Equipment (PPE) within the Precautionary Statements and Agricultural Use Requirements, if applicable
Respiratory Protection for labels allowing use in Nurseries and on Hops, which do not prohibit application with a mechanically pressurized handgun
                                       
Note: Registrants should adjust the PPE statement depending on the uses allowed in the end-use product label.
"In addition to the PPE above, Mixers, Loaders, and Applicators using mechanically-pressurized handguns when applying to nursery sites (ornamentals, vegetables, trees, container stock) and/or hops must"

[Note to registrant: If your end-use product only requires protection from particulates only (low volatility), use the following language]

"Wear a minimum of:
 a NIOSH-approved elastomeric half mask respirator with organic vapor (OV) cartridges and combination N1, R, or P filters; OR
 a NIOSH-approved gas mask with OV canisters; OR
 a NIOSH-approved powered air purifying respirator with OV cartridges and combination HE filters."

*Drop the "N" option if there is oil in the product's formulation and/or the product is labeled for mixing with oil-containing products.

[Note to registrant: For respiratory protection from organic vapor and particulates (or aerosols), use the following language:]
"Wear a minimum of a NIOSH-approved elastomeric half mask respirator with organic vapor (OV) cartridges and combination N*, R, or P filters; OR a NIOSH-approved gas mask with OV canisters; OR a NIOSH-approved powered air purifying respirator with OV cartridges and combination HE filters."

[Note to registrant: For products requiring protection for organic vapor only, use the following language:] 
"Wear a minimum of a NIOSH-approved elastomeric half mask respirator with organic vapor (OV) cartridges; OR a NIOSH-approved full face respirator with OV cartridges; OR a gas mask with OV canisters; OR a powered air purifying respirator with OV cartridges." 

*Drop the "N" option if there is oil in the product's formulation and/or the product is labeled for mixing with oil-containing products.
In the Personal Protective Equipment (PPE) within the Precautionary Statements
                         Requirements for Non-WPS Uses
Respirator fit testing, medical qualification, and training 
Using a program that conforms to OSHA's requirements (see 29 CFR Part 1910.134), employers must verify that any handler who uses a respirator is:
 Fit-tested and fit-checked,
 Trained, and 
 Examined by a qualified medical practitioner to ensure physical ability to safely wear the style of respirator to be worn. A qualified medical practitioner is a physician or other licensed health care professional who will evaluate the ability of a worker to wear a respirator. The initial evaluation consists of a questionnaire that asks about medical conditions (such as a heart condition) that would be problematic for respirator use. If concerns are identified, then additional evaluations, such as a physical exam, might be necessary. The initial evaluation must be done before respirator use begins. Handlers must be reexamined by a qualified medical practitioner if their health status or respirator style or use-conditions change. 
Upon request by local/state/federal/tribal enforcement personnel, employers must provide documentation demonstrating how they have complied with these requirements."
Precautionary Statements under the heading "Hazards to Humans and Domestic Animals"
                         Non-target Organism Advisory
"NON-TARGET ORGANISM ADVISORY: This product is toxic to plants and may adversely impact the forage and habitat of non-target organisms, including pollinators, in areas adjacent to the treated site.  Protect the forage and habitat of non-target organisms by following label directions intended to minimize spray drift."
Environmental Hazards section of the label, under the general heading "Precautionary Statements" 
                            Surface Water Advisory
"Do not apply directly to water, or to areas where surface water is present or to intertidal areas below the mean high water mark. Do not contaminate water when disposing of equipment washwater or rinsate. Drift and runoff may be hazardous to aquatic organisms in water adjacent to treated areas. This product may impact surface water quality due to runoff of rainwater. This is especially true for poorly draining soils and soils with shallow ground water."

Environmental Hazards section of the label, under the general heading "Precautionary Statements"
                            Ground Water Advisory 
                   (specify dimethenamid or dimethenamid-p)
"[Name of chemical] is known to leach through soil into groundwater under certain conditions as a result of label use. This chemical may leach into groundwater if used in areas where soils are permeable, particularly where the water table is shallow."
Environmental Hazards section of the label, under the general heading "Precautionary Statements"
                           For granular formulations
"Granules exposed on soil surface may be hazardous to wildlife. Cover or collect
granules spilled during loading".
Environmental Hazards
                        Herbicide Resistance Management
                                       
                                       
                                       
Include resistance management label language for herbicides from PRN 2017-1 and PRN 2017-2 (https://www.epa.gov/pesticide-registration/pesticide-registration-notices-year)
   

Directions for Use, prior to directions for specific crops under the heading "WEED RESISTANCE- MANAGEMENT"
                  Labels allowing use on lentils or dry beans
The labels of all products registered for use on lentils should be revised to list lentils as a separate use site from dry beans.
                              Directions for Use
                  Labels of liquid products allowing use on 
nursery sites (ornamentals, vegetables, trees, container stock) that do not prohibit use with a mechanically pressurized handgun)
Applications to nursery sites (ornamentals, vegetables, trees, container stock) must use at least 30 Gallons Per Acre when applications are made using mechanically- pressurized handguns. 

             Directions for Use in the directions for nursery uses
           Labels allowing use for impregnating dry bulk fertilizer
"Apply 300 to 1,000 pounds of the fertilizer and herbicide blend per acre. Application must be made uniformly to the soil to prevent possible crop injury and for satisfactory weed control. Impregnated fertilizer spread at 1/2 rate and overlapped to obtain a full rate will offer a more uniform distribution."
             Directions for Use in the Dry Bulk Fertilizer section
Spray Drift Management Application Restrictions for all products delivered via liquid spray application and allow aerial application
"MANDATORY SPRAY DRIFT MANAGEMENT
Aerial Applications: 
 --------------------------------------------------------------------------------
   Do not release spray at a height greater than 10 ft above the ground or vegetative canopy, unless a greater application height is necessary for pilot safety.
    Applicators are required to select a nozzle and pressure that deliver a Medium or Coarser droplet size (ASABE S641). 
    If the windspeed is 10 miles per hour or less, applicators must use (1/2) swath displacement upwind at the downwind edge of the field.  When the windspeed is between 11-15 miles per hour, applicators must use (3/4) swath displacement 
    Do not apply when wind speeds exceed 15 mph at the application site. If the windspeed is greater than 10 mph, the boom length must be 65% or less of the wingspan for fixed wing aircraft and 75% or less of the rotor diameter for helicopters. Otherwise, the boom length must be 75% or less of the wingspan for fixed-wing aircraft and 90% or less of the rotor diameter for helicopters.
Directions for Use, in a box titled "Mandatory Spray Drift Management" under the heading "Aerial Applications" 
Placement for these statements should be in general directions for use, before and use-specific directions for use
Spray Drift Management for products that are applied as liquids and allow ground boom applications
"MANDATORY SPRAY DRIFT MANAGEMENT
Ground Boom Applications: 
 --------------------------------------------------------------------------------
   User must only apply with the release height recommended by the manufacturer, but no more than 4 feet above the ground or crop canopy.
    Applicators are required to select a nozzle and pressure that deliver a Medium or Coarser droplet size (ASABE S572).
    Do not apply when wind speeds exceed 15 mph at the application site. Do not apply during temperature inversions."
Directions for Use, in a box titled "Mandatory Spray Drift Management" under the heading "Ground Boom Applications"
Advisory Spray Drift Management Language for all products delivered via liquid spray application
"SPRAY DRIFT ADVISORIES
THE APPLICATOR IS RESPONSIBLE FOR AVOIDING OFF-SITE SPRAY DRIFT.
BE AWARE OF NEARBY NON-TARGET SITES AND ENVIRONMENTAL CONDITIONS.

IMPORTANCE OF DROPLET SIZE
An effective way to reduce spray drift is to apply large droplets. Use the largest droplets that provide target pest control. While applying larger droplets will reduce spray drift, the potential for drift will be greater if applications are made improperly or under unfavorable environmental conditions.

Controlling Droplet Size  -  Ground Boom (note to registrants: remove if ground boom is prohibited on product labels)
:: Volume - Increasing the spray volume so that larger droplets are produced will reduce spray drift. Use the highest practical spray volume for the application.  If a greater spray volume is needed, consider using a nozzle with a higher flow rate.
:: Pressure - Use the lowest spray pressure recommended for the nozzle to produce the target spray volume and droplet size.
:: Spray Nozzle - Use a spray nozzle that is designed for the intended application. Consider using nozzles designed to reduce drift.

Controlling Droplet Size  -  Aircraft (note to registrants: remove if aerial application is prohibited on product labels)
:: Adjust Nozzles - Follow nozzle manufacturers' recommendations for setting up nozzles.  Generally, to reduce fine droplets, nozzles should be oriented parallel with the airflow in flight.

BOOM HEIGHT  -  Ground Boom (note to registrants: remove if ground boom is prohibited on product labels)
For ground equipment, the boom should remain level with the crop and have minimal bounce.

RELEASE HEIGHT - Aircraft (note to registrants: remove if aerial application is prohibited on product labels)
Higher release heights increase the potential for spray drift.  

SHIELDED SPRAYERS
Shielding the boom or individual nozzles can reduce spray drift.  Consider using shielded sprayers.  Verify that the shields are not interfering with the uniform deposition of the spray on the target area.

TEMPERATURE AND HUMIDITY
When making applications in hot and dry conditions, use larger droplets to reduce effects of evaporation.

TEMPERATURE INVERSIONS
Drift potential is high during a temperature inversion. Temperature inversions are characterized by increasing temperature with altitude and are common on nights with limited cloud cover and light to no wind. The presence of an inversion can be indicated by ground fog or by the movement of smoke from a ground source or an aircraft smoke generator. Smoke that layers and moves laterally in a concentrated cloud (under low wind conditions) indicates an inversion, while smoke that moves upward and rapidly dissipates indicates good vertical air mixing. Avoid applications during temperature inversions. 

WIND
Drift potential generally increases with wind speed.  AVOID APPLICATIONS DURING GUSTY WIND CONDITIONS.
Applicators need to be familiar with local wind patterns and terrain that could affect spray drift."
Directions for Use, just below the Spray Drift box, under the heading "Spray Drift Advisories"
Advisory Spray Drift Management Language for all products that allow liquid applications with handheld technologies
"SPRAY DRIFT ADVISORIES
Handheld Technology Applications: 
 --------------------------------------------------------------------------------
   Take precautions to minimize spray drift."

   
Directions for Use, just below the Spray Drift box, under the heading "Spray Drift Advisories"



 Appendix C:  Endangered Species Assessment

In 2013, EPA, along with the Fish and Wildlife Service (FWS), the National Marine Fisheries Service (NMFS), and the United States Department of Agriculture (USDA) released a summary of their joint Interim Approaches for assessing risks to endangered and threatened (listed) species from pesticides. These Interim Approaches were developed jointly by the agencies in response to the National Academy of Sciences' (NAS) recommendations that discussed specific scientific and technical issues related to the development of pesticide risk assessments conducted on federally threatened and endangered species. 

Since that time, EPA has conducted biological evaluations (BEs) on three pilot chemicals representing the first nationwide pesticide consultations (final pilot BEs for chlorpyrifos, malathion, and diazinon were completed in January 2017). These initial pilot consultations were envisioned to be the start of an iterative process. The agencies are continuing to work to improve the consultation process. For example, after receiving input from the Services and USDA on proposed revisions to the pilot interim method and after consideration of public comments received, EPA released an updated Revised Method for National Level Listed Species Biological Evaluations of Conventional Pesticides (i.e., Revised Method) in March 2020. During the same timeframe, EPA also released draft BEs for carbaryl and methomyl, which were the first to be conducted using the Revised Method.

Also, a provision in the December 2018 Farm Bill included the establishment of a FIFRA InterAgency Working Group (IWG) to provide recommendations for improving the consultation process required under section 7 of the Endangered Species Act for pesticide registration and Registration Review and to increase opportunities for stakeholder input. This group includes representation from EPA, NMFS, FWS, USDA, and the Council on Environmental Quality (CEQ). Given this new law and that the first nationwide pesticide consultations were envisioned as pilots, the agencies are continuing to work collaboratively as consistent with the congressional intent of this new statutory provision. EPA has been tasked with a lead role in this group, and EPA hosted the first Principals Working Group meeting on June 6, 2019. The recommendations from the IWG and progress on implementing those recommendations are outlined in reports to Congress. 

Given that the agencies are continuing to work toward implementation of the Revised Method to assess the potential risks of pesticides to listed species and their designated critical habitat, the ecological risk assessment supporting this PID for dimethenamid/-p does not contain a complete ESA analysis that includes effects determinations for specific listed species or designated critical habitat. Although EPA has not yet completed effects determinations for specific species or habitats, for this PID, EPA's evaluation assumed, for all taxa of non-target wildlife and plants, that listed species and designated critical habitats may be present in the vicinity of the application of dimethenamid/-p. This will allow EPA to focus its future evaluations on the types of species where the potential for effects exists once the Revised Method has been fully implemented. Once that occurs, the Revised Method will be applied to subsequent analyses for dimethenamid/-p as part of completing this registration review.

 Appendix D: 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, sub-chronic 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 dimethenamid/-p, the 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 § 408(p), dimethenamid/-p 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 § 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. The Agency has reviewed all of the assay data received for the List 1 chemicals and the conclusions of those reviews are available in the chemical-specific public dockets. Neither of these lists should be construed as a list of known or likely endocrine disruptors. Dimethenamid/-p is not on either list. For further information on the status of the EDSP, the policies and procedures, the lists of chemicals, future lists, the test guidelines and the Tier 1 screening battery, visit the EPA website.  

In this PID, EPA is making no human health or environmental safety findings associated with the EDSP screening of dimethenamid/-p. Before completing this registration review, the Agency will make an EDSP FFDCA § 408(p) determination."
      


