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AGENDA

FIFRA SCIENTIFIC ADVISORY PANEL (SAP)

OPEN MEETING

November 29 - December 1, 2011

FIFRA SAP WEB SITE http://www.epa.gov/scipoly/sap/

OPP Docket Telephone: (703) 305-5805

Docket Number: EPA-HQ-OPP-2011-0718

U.S. Environmental Protection Agency

Conference Center - Lobby Level

One Potomac Yard (South Bldg.)

2777 S. Crystal Drive, Arlington, VA 22202

Scientific Conclusions Supporting EPA's FIFRA Section 6(b) Notice of Intent to Cancel Twenty 

Homeowner Rodenticide Bait Products

Please note that all times are approximate (see note at end of Agenda).

Day 1

Tuesday, November 29, 2011

8:30 a.m. Opening of Meeting and Administrative Procedures - Joseph Bailey, Designated 

Federal Official, Office of Science Coordination and Policy, EPA

8:35 a.m. Welcome and Introduction of Panel Members - Kenneth Portier, Ph.D., FIFRA 

Scientific Advisory Panel Chair

8:45 a.m. Opening Remarks - Steven Bradbury, Ph.D., Director, Office of Pesticide Programs

(OPP), EPA

9:00 a.m. Regulatory History - Russell Wasem, M.S., Pesticide Re-evaluation Division, OPP, EPA 

9:15 a.m. Commensal Rodenticides: Pesticides and Pesticide Products Used to Control 

Norway Rats, Roof Rats and/or House Mice - William Jacobs, Ph.D., Registration 

Division, OPP, EPA

9:45 a.m. The Rodenticides NOIC - A Toxicological Overview - Ray Kent, Ph.D., Health Effects 

Division (HED), OPP, EPA

10:00 a.m. Rodenticides: Human Incident Analysis - Shanna Recore, HED, OPP, EPA

10:30 a.m. Break

10:45 a.m. Rodenticides: Pet Incident Analysis - Sarah Winfield, HED, OPP, EPA

11:15 a.m. Ecological Risk Assessment of Rodenticides - Introduction and Overview - Edward 

Odenkirchen, Ph.D., Environmental Fate and Effects Division (EFED), OPP, EPA 

11:30 a.m. Toxicity and Elimination: Primary Exposure and Risk Characterization - Christine 

Hartless, M.Stat., Ph.D., EFED, OPP 
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12:30 p.m. Lunch

1:30 p.m. Rodenticide Secondary Exposure and Risk Characterization - Elizabeth Riley, M.S., 

EFED, OPP, EPA 

2:30 p.m. Reported Wildlife Incidents for Rodenticides - Justin Housenger, M.S., EFED, OPP, 

EPA

3:15 p.m. Break

3:30 p.m. Conclusions from Ecological Risk Assessment for Rodenticides - Edward 

Odenkirchen, Ph.D., EFED, OPP, EPA 

4:00 p.m. Public Comments

5:30 p.m. Meeting Adjourns

Day 2

Wednesday, November 30, 2011

8:30 a.m. Opening of Meeting and Administrative Procedures – Joseph Bailey, Designated 

Federal Official, Office of Science Coordination and Policy, EPA

8:35 a.m. Introduction of Panel Members – Kenneth Portier, Ph.D., FIFRA Scientific Advisory 

Panel Chair

8:45 a.m. Public Comments Continued

10:15 a.m. Follow-up from Previous Day's Presentations

10:30 a.m. Break

10:45 a.m. Charge to Panel - Charge Question 1: Does the Agency’s analysis of the mammalian 

toxicity studies and human incident reports provide a reasonable basis for concluding that 

exposure to warfarin, brodifacoum, difethialone and/or bromethalin can cause health 

effects in individuals who ingest these rodenticides? Are the adverse effects described in 

the children’s incident reports [e.g., anemia, melena (bloody stool), hematemesis 

(vomiting of blood)], credible consequences of exposure to these active ingredients? 

Please provide the basis for your conclusions.

11:15 a.m. Charge to Panel - Charge Question 2: The human incident report summarizes a 

number of data and information sources used in the analyses and reviews conducted. 

Based on the incident report analysis, EPA has concluded that there are a large number 

of rodenticide exposure incidents that involve children less than 6 years old. While 

exposure generally results in no clinical harm to children, the exposures to rodenticides 

have the potential to result in severe outcomes and/or require medical care or follow-up. 

Does the SAP concur with the EPA’s conclusions regarding the extent of exposures, 

potential severity of effects, and degree of risks posed to humans? Are the conclusions 

reached reasonably supported by the data analysis? Please explain the basis of your 

position.
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11:45 a.m. Charge to Panel - Charge Question 3: Based on the human incident report, EPA 

concludes that the use of conforming rodenticide products will reduce the risk 

rodenticides pose to humans by reducing the opportunity for exposure. Is it reasonable to 

expect that limiting consumer use to conforming rodenticide products will generally 

reduce the opportunity for exposure of humans to commensal rodenticide products? 

Please provide the basis for your conclusions.

12:15 p.m. Lunch

1:15 p.m. Charge to Panel - Charge Question 4: The pet incident report summarizes a number 

of data and information sources used in the analyses and reviews conducted. The EPA 

concludes that there is a high frequency of reported pet incidents involving rodenticides, 

many of which result in severe outcomes; this conclusion is further supported by the 

information reported in the open literature as well as the characterization of primary 

acute risk. Does the SAP concur with EPA’s conclusions of the risks posed to pets by 

non-conforming rodenticide products? Are the conclusions reached reasonably 

supported by the data analysis? Please explain the basis of your position.

2:00 p.m. Charge to Panel - Charge Question 5: The pet analysis has relied on the assessment 

of risks to wildlife from primary exposure as one line of evidence to characterize primary 

acute risk to pets from non-conforming rodenticide products. Is it reasonable to 

conclude that risks to pets are similar to risks to non-target mammalian wildlife, 

assuming comparable exposures? Please explain the basis of your conclusions.

2:30 p.m. Charge to Panel - Charge Question 6: Based on the pet incident report, EPA 

concludes that the use of conforming rodenticide products will reduce the opportunity for 

exposure of pets to rodenticides. Is it reasonable to expect that limiting consumer use 

to conforming rodenticide products will generally reduce the opportunity for exposure of 

pets to commensal rodenticide products? Please provide the basis for your 

conclusions.

3:00 p.m. Break

3:15 p.m. Charge to Panel - Charge Question 7a: The EPA has conducted a deterministic risk 

assessment to evaluate the risks of acute toxicity to non-target mammals and birds from 

primary exposure to non-conforming rodenticide products. In its assessment, EPA 

calculated risk quotients on an acute oral dose and acute dietary exposure basis for 

birds and mammals and further characterized the opportunity for exposure at lethal 

levels based on factors including the number of days required to feed and the mass of 

pesticide required to be consumed to reach lethal thresholds. Using the best available 

data, EPA made assumptions relative to toxicity, accumulation, and clearance of the 

pesticides that are material to the exposure and effects modeling in the deterministic 

primary risk assessment.

Please comment on the reasonableness of the following aspects of EPA’s primary 

exposure deterministic risk assessment: 
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• Selection of toxicity endpoints for species common to all assessed chemicals in 

light of the incomplete overlap across available data sets; 

• The use of allometric toxicity scaling approaches for birds; 

• The reliance on mammalian first order liver or plasma elimination half lives to 

estimate whole body wildlife (birds and mammals) elimination rates for 

anticoagulants and bromethalin, respectively;

• The use of the time required and the consumption of rodenticide mass required 

to reach lethal thresholds as a means of comparing the relative risks of acute 

mortality following consumption of rodenticide bait. 

4:15 p.m. Charge to Panel - Charge Question 7b: In addition, does the Panel concur with 

EPA’s analysis and conclusion that use of non-conforming rodenticide products (i.e., not 

in bait stations) can cause adverse effects to non-target wildlife? Please provide a 

basis for your conclusions.

5:00 p.m. Meeting Adjourns

Day 3

Thursday, December 1, 2011

8:30 a.m. Opening of Meeting and Administrative Procedures – Joseph Bailey, Designated 

Federal Official, Office of Science Coordination and Policy, EPA

8:35 a.m. Introduction of Panel Members – Kenneth Portier, Ph.D., FIFRA Scientific Advisory 

Panel Chair

8:45 a.m. Follow-up from Previous Day Discussions

9:00 a.m. Charge to Panel - Charge Question 7c: Is it reasonable to expect that placing 

rodenticide products in tamper resistant bait stations with formulations expected to 

remain in the bait station will generally reduce the opportunity for primary exposure of 

wildlife to commensal rodent control products? Please provide a basis for your 

conclusions.

9:45 a.m. Charge to Panel - Charge Question 8a: The EPA has conducted a deterministic risk 

assessment to evaluate risks of acute toxicity to non-target mammals and birds from 

secondary exposure to non-conforming rodenticide products. In its exposure estimate, 

EPA used both calculated theoretical contamination levels in prey and available 

empirical data. EPA also characterized the secondary exposure risk using secondary 

feeding studies and factors including the number of contaminated animals required to 

be consumed to reach lethal exposure thresholds. For these analyses, using the best 

available data, EPA made assumptions relative to toxicity, accumulation, and clearance 

of the pesticide that are material to the exposure and effects modeling in the 

deterministic secondary exposure risk assessment.

Please comment on the reasonableness of the following aspects of EPA’s secondary 

exposure deterministic risk assessment: 
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• The use of theoretical body burden calculation together with empirical whole 

body residue data to produce a reasonable range of estimated exposures for 

secondary exposure pathways; 

• The use of the number of prey items required to reach lethal thresholds as a 

means of comparing the relative risks across the assessed rodenticides of acute 

mortality following consumption of contaminated prey; 

• The conclusion that the results of predator / scavenger feeding studies are 

consistent with the findings of the deterministic secondary risk assessment;

• The use of a standardized set of avian toxicity endpoints (i.e., species tested 

across all the assessed chemicals) in light of information on diphacinone 

suggesting that raptors may be more sensitive than the surrogate avian species 

used in the risk assessment.

10:30 a.m. Break

10:45 a.m. Charge to Panel - Charge Question 8b: Does the Panel concur with EPA’s analysis 

and conclusion that consumption of living or dead rodents poisoned by brodifacoum or 

difethialone presents a greater opportunity for adverse effects to non-target wildlife 

compared with the rodenticides warfarin, diphacinone, chlorophacinone, or 

bromethalin? Please provide a basis for your conclusions. Does the Panel concur that 

cancellation of products containing brodifacoum and difethialone sold to residential 

consumers will reduce the opportunity for secondary exposure for wildlife to 

rodenticides? Please provide a basis for your conclusions.

11:30 a.m. Charge to Panel - Charge Question 9a: Incident data demonstrate that rodenticide 

use can result in wildlife mortality, and that such wildlife mortalities occur in urban and 

suburban areas. Based on this incident data, EPA has concluded that consumer use of 

rodenticides in urban and suburban areas may be a significant contributor to the wildlife 

mortalities attributable to rodenticides. The EPA also determined that both primary and 

secondary poisonings have been documented.

As part of its analysis of incidents, EPA analyzed the available incident data in order to 

associate incidents with specific land use categories, i.e., agricultural, urban, suburban 

areas. In performing this analysis, EPA relied on the information in incident reports 

identifying associated habitat or on the address reported for the incident and then used 

remote sensing information to assign a land use category with the incident. Please 

comment on the reasonableness of this approach to using location information to 

support the conclusion that use of the commensal rodenticides addressed in the draft 

NOIC causes wildlife mortalities in urban and suburban areas, as well as rural areas.

12:15 p.m. Lunch

1:15 p.m. Charge to Panel - Charge Question 9b: EPA analyzed the available incident data in 

order to differentiate primary and secondary wildlife mortality. For this analysis, EPA 

relied on information on the dietary requirements of the moribund species and any 

identified gut contents when available. Does the Panel find this approach a reasonable 

way to evaluate the occurrence of primary and secondary toxicity as causes of wildlife 

mortality? Please provide the basis for your conclusions.
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2:00 p.m. Charge to Panel - Charge Question 10: EPA requires registrants of commensal 

rodent control products to demonstrate that their products meet criteria for efficacy. The 

registrants of conforming rodenticide products have submitted such data to EPA, and 

EPA has determined that their products meet these criteria. Do the meeting of these 

efficacy performance criteria and EPA’s analysis of the effectiveness of conforming 

rodenticide products reasonably support conclusions that conforming rodenticide 

products provide effective options for chemical control of commensal rodents by 

nonprofessional users? If you conclude that conforming rodenticide products do not 

provide effective options for chemical control of commensal rodents by nonprofessional 

users, please discuss to what extent the following requirements affect the availability to 

consumers of effective options for control of commensal rodents:

• The requirement that rodenticides sold to residential consumers must include 

tamper-resistant bait stations;

• The requirement that rodenticides sold to residential consumers must be in forms 

(e.g. bait blocks) which are reasonably expected to remain within the bait station; 

and 

• The requirement that rodenticides sold to residential consumers not contain the 

active ingredients brodifacoum, difethialone, bromadiolone, or difenacoum.

Please provide the basis for your conclusions.

2:45 p.m. Break

3:00 p.m. Charge to Panel - Charge Question 11: Are conforming rodenticide products 

containing the active ingredients warfarin, diphacinone, chlorophacinone, or 

bromethalin, along with non-chemical rodent control methods available to consumers 

and other options, capable of providing effective control of commensal rodents? Please 

provide the basis for your conclusions.

3:45 p.m. Charge to Panel (continued as needed)

4:30 p.m. Meeting Wrap-up and Final Panel Comments

5:00 p.m. Meeting Adjourns

Please be advised that agenda times are approximate; when the discussion for one topic is 

completed, discussions for the next topic will begin. For further information, please contact the 

Designated Federal Official for this meeting, Joseph Bailey, via telephone: (202) 564-2045; fax:

(202) 564-8382; or email: bailey.joseph@epa.gov