ScientificIssuesAssociatedwith EPA’se t c ssues ssoc ated t sProposed Cancellation & Denial ofCertain RodenticideProductsSc e t c ssues ssoc ated t sProposed Cancellation & Denial ofCertain RodenticideProductsta ode t c de oductsCharge QuestionsRisks to HumansQuestion 1•Does the Agency’s analysis of the mammaliany ytoxicity studies and human incident reportsprovide a reasonable basis for concluding thatexposure to warfarin brodifacoum difethialoneexposuretowarfarin,brodifacoum,difethialoneand/or bromethalin can cause health effects inindividuals who ingest these rodenticides? Areffthe adverse eects described in the children’sincident reports [e.g., anemia, melena (bloodystool),hematemesis(vomitingof blood)],credible( g )],consequences of exposure to these activeingredients? Please provide the basis for yourconclusions.2Risks to HumansQuestion 2•The human incident report summarizes a number of dataand information sources used in the analyses and reviewsconducted. Based on the incident report analysis, EPAh l d d th t th l b f d ti idhas concludedthatthere are alarge number ofrodenticideexposure incidents that involve children less than 6 yearsold. While exposure generally results in no clinical harm tochildren the exposures to rodenticides have the potentialchildren,theexposurestorodenticideshavethepotentialto result in severe outcomes and/or require medical care orfollow-up. Does the SAP concur with the EPA’sconclusions regarding the extent of exposures potentialconclusionsregardingtheextentofexposures,potentialseverity of effects, and degree of risks posed to humans?Are the conclusions reached reasonably supported by thedata analysis? Please explain the basis ofyourposition.p yp3Risks to HumansQuestion3•Based on the human incident report, EPAconcludes that the use of conforming rodenticideproducts will reduce the risk rodenticides pose toproductswillreducetheriskrodenticidesposetohumans by reducing the opportunity forexposure. Is it reasonable to expect that limitingconsumer use to conforming rodenticideproducts will generally reduce the opportunity forexposure of humans to commensal rodenticideproducts? Please provide the basis for yourconclusions.4Risks to PetsQuestion4•The pet incident report summarizes a number of data andThepetincidentreportsummarizesanumberofdataandinformation sources used in the analyses and reviewsconducted. The EPA concludes that there is a highfrequency of reported pet incidents involving rodenticides,frequencyofreportedpetincidentsinvolvingrodenticides,many of which result in severe outcomes; this conclusionis further supported by the information reported in the openliterature as well as the characterization ofprimaryacuteyrisk. Does the SAP concur with EPA’s conclusions of therisks posed to pets by non-conforming rodenticideproducts? Are the conclusions reached reasonablysupported by the data analysis? Please explain the basis ofyour position.5Risks to PetsQuestion5•The pet analysis has relied on the assessment ofrisks to wildlife from primary exposure as oneline of evidence to characterize primary acute risklineofevidencetocharacterizeprimaryacuteriskto pets from non-conforming rodenticideproducts. Is it reasonable to conclude that risksto pets are similar to risks to non-targetmammalian wildlife, assuming comparableexposures? Please explain the basis ofyourpyconclusions.6Risks to PetsQuestion 6•Based on the pet incident report, EPA concludesthat the use of conformingrodenticideproductspwill reduce the opportunity for exposure of petsto rodenticides. Is it reasonable to expect thatlimiting consumer use to conforming rodenticidelimitingconsumerusetoconformingrodenticideproducts will generally reduce the opportunity forexposure of pets to commensal rodenticided ? Pl id h b i fproducts?Please provide thebasisfor yourconclusions.7Risks to WildlifeQuestion7Th EPA h d t d d t i i ti i k t t•TheEPAhas conductedadeterministic riskassessmenttoevaluate the risks of acute toxicity to non-target mammals andbirds fromprimaryexposure to non-conforming rodenticideproducts In its assessment EPA calculated risk quotients onproducts.Initsassessment,EPAcalculatedriskquotientsonan acute oral dose and acute dietary exposure basis for birdsand mammals and further characterized the opportunity forexposure at lethal levels based on factors including the numberexposureatlethallevelsbasedonfactorsincludingthenumberof days required to feed and the mass of pesticide required tobe consumed to reach lethal thresholds. Using the bestavailable data,EPA made assumptions relative to toxicity,p y,accumulation, and clearance of the pesticides that are materialto the exposure and effects modeling in the deterministicprimary risk assessment.8Risks to WildlifeQuestion 7CONT.a)Please comment on the reasonableness of thefollowing aspects of EPA’s primary exposuredeterministic risk assessment:•Selection of toxicity endpoints for species common to allSelectionoftoxicityendpointsforspeciescommontoallassessed chemicals in light of the incomplete overlapacross available data sets;•The use of allometric toxicity scaling approaches for birds;Theuseofallometrictoxicityscalingapproachesforbirds;•The reliance on mammalian first order liver or plasmaelimination half lives to estimate whole body wildlife (birdsand mammals) elimination rates for anticoagulants andandmammals)eliminationratesforanticoagulantsandbromethalin, respectively;•The use of the time required and the consumption ofrodenticide mass required to reach lethal thresholds as arodenticidemassrequiredtoreachlethalthresholdsasameans of comparing the relative risks of acute mortalityfollowing consumption of rodenticide bait;9Risks to WildlifeQuestion 7CONT.b)In addition does the Panel concur with EPA’Inaddition,doesthePanelconcurwithEPA sanalysis and conclusion that use of non-conformingrodenticide products (i.e., not in bait stations) cand ff t tt t ildlif ? Plcause adverse effectsto non-targetwildlife?Pleaseprovide a basis for your conclusions.c)Is it reasonable to expect that placing rodenticideIsitreasonabletoexpectthatplacingrodenticideproducts in tamper resistant bait stations withformulations expected to remain in the bait stationwill generally reduce the opportunity for primarywillgenerallyreducetheopportunityforprimaryexposure of wildlife to commensal rodent controlproducts? Please provide a basis for yourconclusions.10Risks to WildlifeQuestion 8•The EPA has conducted a deterministic risk assessment toTheEPAhasconductedadeterministicriskassessmenttoevaluate risks of acute toxicity to non-target mammals and birdsfromsecondaryexposure to non-conforming rodenticideproducts. In its exposure estimate, EPA used both calculatedproducts.Initsexposureestimate,EPAusedbothcalculatedtheoretical contamination levels in prey and available empiricaldata. EPA also characterized the secondary exposure risk usingsecondaryfeedingstudies and factors includingthe number ofg gcontaminated animals required to be consumed to reach lethalexposure thresholds. For these analyses, using the best availabledata, EPA made assumptions relative to toxicity, accumulation,and clearance of the pesticide that are material to the exposureand effects modeling in the deterministic secondary exposure riskassessment.11Risks to WildlifeQuestion 8CONT.a)Please comment on the reasonableness of the followingaspects of EPA’s secondary exposure deterministic riskassessment:•The use of theoretical body burden calculation together withempirical whole body residue data to produce a reasonable range ofestimated exposures for secondary exposure pathways;•The use of the number of prey items required to reach lethalthresholds as a means of comparing the relative risks across thethresholdsasameansofcomparingtherelativerisksacrosstheassessed rodenticides of acute mortality following consumption ofcontaminated prey;•The conclusion that the results ofpredator / scavenger feedingggstudies are consistent with the findings of the deterministicsecondary risk assessment;•The use of a standardized set of avian toxicity endpoints (i.e., speciest t d ll th d h i l ) i li ht f i f titestedacross allthe assessedchemicals)inlightofinformation ondiphacinone suggesting that raptors may be more sensitive than thesurrogate avian species used in the risk assessment.12Risks to WildlifeQuestion 8CONT.b)Does the Panel concur with EPA’s analysis and conclusionthat consumption of living ordead rodents poisoned bybrodifacoum or difethialone presents a greater opportunityfor adverse effects to non-target wildlife compared with therodenticides warfarin, diphacinone, chlorophacinone, orbromethalin? Please provide a basis for yourconclusions. Does the Panel concur that cancellation ofproducts containing brodifacoum and difethialone sold toresidential consumers will reduce the opportunity forsecondary exposure for wildlife to rodenticides? Pleasesecondaryexposureforwildlifetorodenticides?Pleaseprovide a basis for your conclusions.13Risks to WildlifeQuestion 9•Incident data demonstrate that rodenticide use canresult in wildlife mortality, and that such wildlifemortalities occur in urban and suburban areasmortalitiesoccurinurbanandsuburbanareas.Based on this incident data, EPA has concludedthat consumer use of rodenticides in urban andsuburban areas may be a significant contributor tothe wildlife mortalities attributable to rodenticides.The EPA also determined that bothprimaryandysecondary poisonings have been documented.14Risks to WildlifeQuestion 9CONT.)A t f it l i f i id t EPA l d thaAs partofits analysis ofincidents,EPAanalyzedtheavailable incident data in order to associate incidents withspecific land use categories, i.e., agricultural, urban,suburban areas In performing this analysis EPA relied onsuburbanareas.Inperformingthisanalysis,EPAreliedonthe information in incident reports identifying associatedhabitat or on the address reported for the incident andthen used remote sensing information to assign a land usethenusedremotesensinginformationtoassignalandusecategory with the incident. Please comment on thereasonableness of this approach to using locationinformation to support the conclusion that use of thecommensal rodenticides addressed in the draft NOICcauses wildlife mortalities in urban and suburban areas, aswell as rural areas.15Risks to WildlifeQuestion 9CONT.b)EPA analyzed the available incident data in order todiff ti t i d d ildlif t lit Fdifferentiate primary andsecondary wildlife mortality.Forthis analysis, EPA relied on information on the dietaryrequirements of the moribund species and any identifiedgut contents when available Does the Panel find thisgutcontentswhenavailable.DoesthePanelfindthisapproach a reasonable way to evaluate the occurrence ofprimary and secondary toxicity as causes of wildlifemortality? Please provide the basis for your conclusionsmortality?Pleaseprovidethebasisforyourconclusions.16Efficacy of ConformingRodenticide ProductsQuestion 10EPA i i t t f l d t t l•EPArequires registrants ofcommensalrodentcontrolproducts to demonstrate that their products meet criteriafor efficacy. The registrants of conforming rodenticideproducts have submitted such data to EPA and EPA hasproductshavesubmittedsuchdatatoEPA,andEPAhasdetermined that their products meet these criteria. Do themeeting of these efficacy performance criteria and EPA’sanalysis of the effectiveness of conforming rodenticideanalysisoftheeffectivenessofconformingrodenticideproducts reasonably support conclusions that conformingrodenticide products provide effective options for chemicalcontrol of commensal rodents bynonprofessional users?pIf you conclude that conforming rodenticide products donot provide effective options for chemical control ofcommensal rodents by nonprofessional users, pleasediscuss to what extent the following requirements affect theavailability to consumers of effective options for control ofcommensal rodents:17Efficacy of ConformingRodenticide ProductsQuestion 10CONT.•The requirement that rodenticides sold to residentialTherequirementthatrodenticidessoldtoresidentialconsumers must include tamper-resistant baitstations;•The requirement that rodenticides sold to residentialconsumers must be in forms (e.g. bait blocks) whichare reasonably expected to remain within the baitarereasonablyexpectedtoremainwithinthebaitstation; and•The requirement that rodenticides sold to residentialt t i th ti i di tconsumers notcontainthe activeingredientsbrodifacoum, difethialone, bromadiolone, ordifenacoum.Please provide the basis for your conclusions.18Efficacy of ConformingRodenticide ProductsQuestion 11•Are conforming rodenticide products containingthe active ingredients warfarin, diphacinone,chlorophacinone, or bromethalin, along with nonchemical rodent control methods available tochemicalrodentcontrolmethodsavailabletoconsumers and other options, capable ofproviding effective control of commensalrodents? Please provide the basis for yourrodents?Pleaseprovidethebasisforyourconclusions.19