Sc e t c ssues ssoc ated t 

ientific Issues Associated with 

Proposed Cancellation & Deni

Certain Rodenticide Produc

Sc e t c ssues ssoc ated t 

Proposed Cancellation & Deni

Ce ta ode t c de oduc

rtain Rodenticide Produc

Regulatory Background

Rusty Wasem, M.S.Chemical Review ManageOffice of Pesticide ProgramOffice of Pesticide Program
Commensal Use Rodenticide A

In

gredients

• 1st Generation Anticoagulants

• warfarin (and its sodium salt)first registered 1950 (and 1954)• diphacinone (and its sodium salt) diphacinone (and its sodium salt) first registered 1960 (and 1962) first registered 1960 (and 1962)• chlorophacinone first registered 1971

• 2nd Generation Anticoagulants 

(AKA Long Acting Anticoagulant Rodenticides or Super Wa(AKA Long Acting Anticoagulant Rodenticides or Super Wa

• brodifacoum first registered 1979• bromadiolone first registered 1980• difethialone first re

gistered 1995

• difenacoum first registered 2007

• Non-Anticoagulants

(AKA Acute Rodenticides) (AKA Acute Rodenticides)

• zinc phosphide first registered 1947

• Homeowner uses are limited to below ground applications for moles, voles, 

gophers

• bromethalin first registered 1984 first registered 1984• cholecalciferol (Vit-D3) first registered 1984

• Currently no homeowner products
Active Ingredients & Products S

this NOI

C

• Products Proposed for Cancelation Contain:

• Bromethalin• Brodifacoum• Difethialone• Warfarin

• Products Proposed for Denial Contain

• Bromethalin• B dif ro acoum

• Product Currently Registered Products for Reside

Consumer Market Contain:

• Bromethalin• Diphacinone• Chlorophacinone
Pre-1998

• 1982 – Registration Standards for Warfarin & Zinc 

Phosphide

• 1983 - Pesticide Registration Notice (PR Notice) 8

• Product labels were to require the statement: “baits must 

locations not accessible to children pets wildlife and domestilocations not accessible to children, pets, wildlife, and domesti

in tamper-proof bait boxes”

• 1991- Warfarin Reregistration Eligibility Decision (

Warfarin Reregistration Eligibility Decision (

• Product labels were to require the use of tamper-resista

stations wherever bait placements would be within the re

children, pets, domestic animals, or non children, pets, domestic animals, or non-target wildlife target wildlife

• 1994 - PR Notice 94-7

• “Tamper-Proof” replaced by replaced by “Tamper-Resistant Resistant” bait sta

bait sta

• Commensal rodents
1998 Rodenticide Cluster RE

Zinc Phosphide RED

• The 1998 REDs only assessed the brodifacou

bromethalin, bromadiolone chlorophacinone, di h i (& it di lt) d i h di

p

hacinone (& its sodium salt), an

d zinc p

hos

• Identical mitigation measures were required for rodentici

containing warfarin (& its sodium salt), difethialone, and cholecalciferol (vit D cholecalciferol (vit. D

-3)

• Mitigation Measures:

• Non-ag baits must incorporate indicator dyes and bitterin• Products formulated as tracking powders to remain restr

products (RUP)

• All products labeled for field uses, except those limited to 

underground baiting were to be reclassified as RUP underground baiting were to be reclassified as RUP

• Organize a stakeholder FACA group to advise 

on rodenticide exposure reduction.

• Further evaluation of ecological risk was need
1999-2004

• 1999-2001-Rodenticide Stakeholder Workgrou

• Formed in 1999 under federally chartered Pesticide 

Di l C i (PPDC) Dialogue Committee (PPDC)

• Recommendations:

• Use of bittering agent should be voluntary• Rescind the indicator dye requirement

• Recommendations adopted in November 2001

• 2001-2004 C 

omparative Ecological Assessme

Rodenticides

• 2004-West Harlem Environmental Action (WEA

Natural Resources Defense Council (NRDC) v

• Challeng g y gg ed Agency’s decision on bittering agent an

dye
2007

Proposed Mitigation Decision

• Commensal uses only• Mitigation Highlights:

• Homeowner products must be so

Homeowner products must be so

with tamper resistant bait station 

could only contain solid block bacould only contain solid block ba

• 2nd generation anticoagulants wo

be classified restricted use prodube classified restricted use produ

(RUP)

• Extensive comments received
2008 Risk Mitigation Decisio

Ten Rodenticides 

( 

RMD

• The Agency’s final reregistration eligibi

d i i f d ti id decision 

for ro

denti

cides

• Commensal uses onl

y for:

• brodifacoum, bromadiolone, bromethalin, 

chlorophacinone, cholecalciferol, difenacoudifethialone diphacinone (and its sodium sdifethialone, diphacinone (and its sodium s

warfarin (and its sodium salt), and zinc pho

• Li it d i t f i l Li

mit

e

d impac

t on pro

fessional users
RMD Mitigation–Children & P

• Risks Identified:

• Accidental child exposure

• Since 1993, 12k-15k cases 15k cases (children <6 years) per (children <6 years) per year

reported

• Rarely do reported exposures result in symptoms

• Accidental pet exposure

• Often result i t n pe d th d i ifi t death an

d significant expense

• Mitigation Required:

• Bait Stations 

• Required for outdoor, above ground use.• Tamper resistant bait stations required if children, pets, nontarget mammals, or birds may access the bait.• Homeowner/retail products must be sold with a bait station; 

and

• Product Packaging Size Requirements

• Homeowner/retail products may not contain more than 1 lb of 

bait.

• F l ti R i t Formulation 

Requiremen

t

s

• Pellets and meal baits prohibited for all “residential consumer” 

products.
RMD Mitigation-Ecological

• Risk Identified: 

• Primary and secondary poisonings of non-target 

d • Well documented presence of 2

n generation (ge

anticoagulants in livers of raptors, foxes, wild cat

• Mitigation Required:

• Reduce availability of 2nd gen. anticoagulants to 

homeowners

•

Prohibit sale of 2nd

•

Prohibit sale of

2 gen products in retail stores nd gen. products in retail stores

• Packaging size requirements for 2nd gen. products 

 8 lbs for agriculture products / 16 lbs for professionals (PCOs)

• Bait Stations 

• Required for all outdoor, above ground uses 
RMD Implementation Timel

• June 2008 : Publish RMD 

• No comment period No comment period• Requested registrants voluntarily adopt RMD miti

through product changes, cancellation of non-con

prod t d i t ti f f i d 

duc

ts, an

d regis

tration o

f new con

forming pro

d

• 3 Years After RMD Publication (June 4, 2011)

• Last day for registrants to release into commerce 

not complying with the risk mitigation decision

• Existin

g stocks of non-com

p p liant 

products release

shipment by the registrant on or before this date cuntil stocks are exhausted
Schedule of Presentations

• Rodenticide Product Efficacy

• Dr. William Jacobs

• Rodenticide Toxicity Overview

• Dr. Ray Kent

• Human Incident Analysis

• Shanna Recore

• Pet Incident Analysis

• Sarah Winfield

• Ecological Risk Introduction & Overview

• D Ed d Od ki h Dr. Edwar

d Odenkirc

hen

• Primary Exposure & Risk Characterization

• Dr. Christine Hartless

• Secondary Exposure & Risk Characterization Secondary Exposure

& Risk Characterization

• Elizabeth Riley, M.S.

• Wildlife Incident Analysis

• Justin Housenger M S Justin Housenger, M.S.

• Ecological Risk Conclusion

• Dr. Edward Odenkirchen 
Thank You! Thank You!

• Rusty Wasem Rusty Wasem

• wasem.russell@epa.gov• (703) 305 (703) 305 - 6979