UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON D.C., 20460 

OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION 

MEMORANDUM 

DATE: September 17, 2014 

SUBJECT: MCPB: PRD Response to Comments on Registration Review Preliminary Work 

Plan 

FROM: Khue Nguyen, Chemical Review Manag")i ~ ""'-./ 

Thomas Moriarty, Team Leader ~ ~ 'f ' l.....,..._· "-"""'-- (f) 

Risk Management and Implementation Branch 1 

Pesticide Re-evaluation Division (7508P) 

THROUGH: Neil Anderson, Branch Chief _ft."'~ (J lf1-~ -(. ,A.J A-... <Lt-.sRisk Management and Implementation Branch 1 

Pesticide Re-evaluation Division (7508P) 

TO: MCPB Registration Review Docket 

Docket Number: EPA-HQ-OPP-20 14-0181 

www.regulations.gov 

On March 28, 2014, EPA opened a 60-day public comment period on the preliminary work plan 

(PWP) for the registration review ofMCPB. The comment period ended on May 27, 2014. During the 

public comment period the Agency received 3 submissions. Comments were submitted by the MCPB 

Task Force, the Center for Biological Diversity, and the FIFRA Endangered Species Task Force 

(FEST F). 

Below are PRD's responses to those comments pertaining to the preliminary work plan for MCPB, the 

use and usage of MCPB, or pertaining to the general MCPB registration review program. Comments 

regarding the environmental fate or effects ofMCPB have been addressed by the Environmental Fate 

and Effects Division's (EFED) document, EPA Response to Comments Related to the Preliminary 

Problem Formulation for Ecological Risk and Environmental Fat?, Endangered Species, and Drinking 

Water Assessments/or MCPB and Its Salt, dated August 28, 2014. Comments regarding the human 

health assessment or human health data requirements have been addressed by the Health Effects 

Division's (HED) document, MCPB. Response to Comments Received Regarding Scoping Document 

in Support of Registration Review, dated September 4, 2014. 

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Comments from the MCPB Task Force in EPA-HQ-OPP-2014-0181-0012 

MCPB Task Force Comment: The MCPB Task Force made corrections to the MCPB LUIS reports 

and suggested that the LUIS reports should be rerun to incorporate new updates. 

EPA Response: The Agency acknowledges these corrections. The LUIS reports are up-to-date as of 

the date the reports were generated. The LUIS reports will be updated again when and if needed for 

risk assessment, but as of this time the reports will not be rerun by the Agency. 

MCPB Task Force Comment: The MCPB Task Force stated that all formulations of MCPB are 

soluble concentrate and not emulsifiable concentrate. 

EPA Response: The Agency acknowledges this correction. 

MCPB Task Force Comment: The Task Force did not understand why an ecological incident 

naming MCP A was attributed to MCP B. 

EPA Response: The single terrestrial plant incident was actually attributed to MCPB. There was a 

typo in the problem formulation. 

Comments from the Center for Biological Diversity in EPA-HQ-OPP-2014-0181-0011 

Center for Biological Diversity Comment: The Center for Biological Diversity's (CBD) comments 

focus on the EPA's duty to consult with the US Fish and Wildlife Service and the National Marine 

Fisheries Service (the Services) on the registration review of MCPB in accordance with the 

Endangered Species Act (ESA). The CBD comments mention various aspects of the risk assessment 

process, including use of the best available data to develop endangered species risk assessments, and 

evaluation of effects on endangered and threatened species and their designated critical habitat. CBD 

also expresses concern regarding the rigor of the Agency's preliminaty determinations regarding the 

effects of MCPB on endangered and threatened (listed) species and their designated critical habitat for 

the MCPB registration review. 

EPA Response: EPA has reviewed the comments from CBD on the registration review docket 

opening for MCPB and plans to address many of the concerns raised by CBD as part of the 

implementation plan for assessing the risks of pesticides to listed species based on the 

recommendations ofthe April2013 National Academy of Sciences (NAS) report. EPA will address 

concerns specific to MCPB in connection with the development of its final registration review decision 

for this pesticid~. 

In November 2013, the EPA, along with the Services and the USDA, released a summary of 

their joint Interim Approaches for assessing risks to endangered and threatened (listed) species from 

pesticides. The Interim Approaches were developed jointly by the agencies in response to the NAS 

recommendations and reflect a common approach to risk assessment shared by the agencies as a way 

of addressing scientific differences between the EPA and the Services. The NAS report outlines 

recommendations on specific scientific and technical issues related to the development of pesticide risk 

assessments that EPA and the Services must conduct in connection with their obligations under the 

ESA and FIFRA. 

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The joint Interim Approaches were released prior to a stakeholder workshop held on November 

15, 20 13. ln addition, the EPA presented the joint Interim Approaches at the December 2013 Pesticide 

Program Dialogue Committee (PPDC) and State-FIFRA Issues Research and Evaluation Group 

(SFIREG) meetings. The agencies also held a stakeholder workshop in April 2014, allowing additional 

opportunities for stakeholders to comment on the Interim Approaches. Additional workshops are 

planned to enhance stakeholder involvement; the next workshop is scheduled for October 2014. As 

part of a phased, iterative process for developing the Interim Approaches, the agencies will also 

consider public comments on the Interim Approaches in connection with the development of upcoming 

registration review decisions. The details of the joint Interim Approaches are contained in the white 

~,Interim Approaches for National-Level Pesticide Endangered Species Act Assessments Based on 

the Recommendations of the National Academy of Sciences April 2013 Report, dated November 1, 

2013. 

Given that the agencies are continuing to develop and work toward implementation of the 

Interim Approaches to assess the potential risks of pesticides to listed species and their designated 

critical habitat, the ecological problem formulation supporting this Final Work Plan for MCPB does 

not describe the specific ESA analysis, including effects determinations for specific listed species or 

designated critical habitat, to be conducted during registration review. In the ecological problem 

formulation document for MCPB, EPA described the screening-level risk assessment to determine the 

potential effects of MCPB on all taxa of non-target wildlife and plants, which will assume that listed 

species and their designated critical habitats may be present in the vicinity of the application ofMCPB. 

This screening-level assessment will allow EPA to focus its future evaluations on the types of species 

where the potential for effects exists once the scientific methods being developed by the agencies have 

been fully vetted. While the agencies continue to develop a common method for ESA analysis, the 

planned screening-level risk assessment for the registration review of MCPB will describe the level of 

ESA analysis completed for this particular registration review case. Once the agencies have fully 

developed and implemented the scientific methods necessary to complete risk assessments for 

endangered and threatened (listed) species and their designated critical habitats, these methods will be 

applied to subsequent analyses for MCPB as part of completing this registration review. 

Comments from the FIFRA Endangered Species Task Force (FESTF) in EPA-HQ-OPP-2014-

0181-0010 

FESTF Comment: FESTF commented that the MCPB technical registrants, Nufarm Limited and 

Nufarm Americas, Inc. , are both FESTF members and are entitled to rely on FESTF data for 

endangered species assessment. 

EPA Response: The Agency thanks FESTF for this information and will consider it during the 

registration review ofMCPB. 

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