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Update on Residential Pesticide Exposure Assessment Standard Operating Procedures (SOPs). DoD Pest Management Workshop Naval Air Station, Jacksonville, FL February 11, 2010 Aaron Niman, LTJG (USPHS) Office of Pesticide Programs Environmental Protection Agency. Outline. Overview
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Update on Residential Pesticide Exposure Assessment Standard Operating Procedures (SOPs) DoD Pest Management Workshop Naval Air Station, Jacksonville, FL February 11, 2010 Aaron Niman, LTJG (USPHS) Office of Pesticide Programs Environmental Protection Agency
Outline • Overview • U.S. EPA’s Office of Pesticide Programs (OPP) • Registration Process • Exposure Assessment • Residential Exposure Assessment SOPs • Scope • Overview of Updates • Example • Future Directions Health Effects Division Office of Pesticide Programs
Overview: OPP • Principal Business • Protect human health and the environment • Realize the value from pesticide availability • Responsible for ensuring the safety of pesticides by conducting multi-pathway and multi-chemical exposure and risk assessments • Food • Water • Residential • Occupational • Environment Health Effects Division Office of Pesticide Programs
Overview: Registration Process Pesticide Registrant EPA Chemical Review Manager Scientific Review/ Risk Assessment Evaluate Human Toxicity Risk Management Human Exposure Assessment Environmental Assessment Health Effects Division Office of Pesticide Programs
Overview: Exposure Assessment Exposure Assessment • Identify applications (Occupational, residential, agricultural) • Determine use patterns (Application Rate, use frequency and location , PPE, etc.) Review Label • Identify potentially exposed population (adults, children, infants) • Determined exposure pathways (inhalation, dermal, ingestion) Identify Exposure Pathways • Select appropriate assumptions and data inputs • Characterize data gaps/ uncertainty Quantify Exposure Health Effects Division Office of Pesticide Programs
Overview: Registration Process Pesticide Registrant EPA Chemical Review Manager Scientific Review/ Risk Assessment Evaluate Human Toxicity Risk Management Human Exposure Assessment Environmental Assessment Health Effects Division Office of Pesticide Programs
Residential Exposure Assessment SOPs Residential SOPs: • Define most common residential exposure scenarios that are evaluated as part of OPP’s risk assessment process • Define exposure equations that are used to quantify exposure • Define the data sources and assumptions that are used quantify exposure • Characterize uncertainty associated with SOPs Health Effects Division Office of Pesticide Programs
Residential SOPs: Purpose • Provide OPP Risk Assessors with guidelines to assess residential pesticide exposure Guidance on how to: • Assess exposure without chemical-specific data • Identify appropriate exposure pathways and routes of exposure • Identify appropriate population groups of concern • Ensure that OPP exposure assessments are transparent to external stakeholders • Identify data gaps where additional data/research could improve future exposure assessments Health Effects Division Office of Pesticide Programs
Residential SOPs: Updates • Draft Updated Residential SOPs recently reviewed by EPA’s Scientific Advisory Panel (10/2009) • Available at www.regulations.gov. Search: “EPA-HQ-OPP-2009-0516”. • Incorporate latest scientific data/research • Peer-reviewed literature • Propriety data submitted as part of registration process • New exposure equations and models • More advanced assessment capabilities (e.g. probabilistic methods) • Incorporate exposure scenarios that were previously assessed but not formally documented • Misting systems • Repellents Health Effects Division Office of Pesticide Programs
Residential SOPs: Updates • Exposure Scenarios • Lawns & Turf • Indoor Environments • Gardens & Trees • Treated Pets Health Effects Division Office of Pesticide Programs
Residential SOPs: Updates • Exposure Scenarios • Outdoor Fogging/Misting Systems* • Impregnated Materials • Insect Repellents* • Paints/Wood Preservatives * Not addressed in previous Residential SOP document. Health Effects Division Office of Pesticide Programs
Residential SOPs: Updates • Potentially Exposed Populations • Select age categories based on factors influencing exposure • Adults and Children (Teens, Youths, Toddlers, Infants) http://www.btny.purdue.edu/Pubs/PPP/PPP-48.pdf Health Effects Division Office of Pesticide Programs
Residential SOPs: Updates • Routes of Exposure • Residential Handler (during application) • Dermal Contact • Inhalation • Residential Post-application • Dermal Contact • Inhalation • Non-Dietary Ingestion (i.e. child object-to-mouth and hand-to-mouth behavior) Health Effects Division Office of Pesticide Programs
Residential SOPs: Updates • Exposure Equations • Quantify potential exposure from specific routes and scenarios • Based on combination of monitoring/observational data and mechanistic models • Equation inputs based on best available data sources • Industry workgroups/ registrant studies • Peer-reviewed literature • EPA guidance documents Health Effects Division Office of Pesticide Programs
Residential SOPs: Updates • Example Equations Dermal and Inhalation Handler Exposure Exposure during the mixing/loading and application of pesticides. Examples include applications of granule applications to lawns using a push-type spreader and applications of liquids to gardens using a hand-held pump sprayer. All residential handler scenarios Exposure = UE * AaiH Where: UE = Unit Exposure (e.g., mg ai/lb ai) AaiH = Amount active ingredient handled (e.g., lb ai) Health Effects Division Office of Pesticide Programs
Residential SOPs: Updates • Example Equations Post-application Dermal Exposure Dermal exposure following pesticide applications as a result of contacting treated surfaces (e.g., playing on lawns or carpets) or as a result of direct deposition (e.g., insect repellents). Lawns/turf, gardens, trees, pets, and indoor surfaces Exposure = TC * CR * ET Where: TC = Transfer Coefficient (e.g., cm2/hr) CR = chemical residue available for surface-to-skin transfer (e.g., mg/cm2) ET = exposure time (e.g., hr) Health Effects Division Office of Pesticide Programs
Residential SOPs: Updates • Example Equations Post-application Inhalation Exposure Inhalation exposure following indoor/outdoor space sprays or via chemical volatilization from surfaces. Examples include outdoor foggers, misting systems in yards or barns, indoor total release aerosols, candles/coils/torches/mats, and indoor surface spray volatilization. Where: IR = inhalation rate (e.g., m3/hr) ET = exposure time (e.g., hrs) C(t) = Concentration at time t t = time (e.g., m3/hr) Health Effects Division Office of Pesticide Programs
Residential Exposure Assessment: Example • Review Label • Determine concentration of active ingredient • Determine product formulations • Identify application methods • Identify potential uses • Identify use restrictions Review Label Identify Exposure Pathways Quantify Exposure Health Effects Division Office of Pesticide Programs
1. Product Formulation Information • Percent active ingredient • Formulation Type 2. Use Directions 3. Warning and Use Restrictions http://www.purdue.edu/envirosoft/housewaste/src/readpest.htm Health Effects Division Office of Pesticide Programs
Residential Exposure Assessment: Example • Identify Exposure Pathways • Link labeled uses to exposure scenarios • Consult Residential Exposure Assessment SOP guidelines on exposure scenarios • Exposure pathways • Duration of exposure • Acute • Short-term • Chronic • Potentially exposed age groups Review Label Identify Exposure Pathways Quantify Exposure Health Effects Division Office of Pesticide Programs
1. Exposure Scenario Granular Lawn Treatment Residential Handler Post-Application 2. Exposed Groups Adults Adults Children 3. Exposure Routes Inhalation Dermal Dermal Dermal Inhalation Object-to-mouth Hand-to-mouth Inhalation Health Effects Division Office of Pesticide Programs
Residential Exposure Assessment: Example • Quantify Exposure • Consult Residential Exposure Assessment SOP guidelines on exposure scenarios • Exposure equations • Residential Handler • Dermal • Inhalation • Ingestion • Assumptions and data inputs • Age-specific inputs • Scenario-specific inputs • Characterize Uncertainty Review Label Identify Exposure Pathways Quantify Exposure Health Effects Division Office of Pesticide Programs
Post-application Dermal Exposure Exposure = TC * CR * ET Where: TC = Transfer Coefficient (e.g., cm2/hr) CR = chemical residue available for surface-to-skin transfer (e.g., mg/cm2) ET = exposure time (e.g., hrs) Health Effects Division Office of Pesticide Programs
Object-to-mouth Exposure Exposure = ((OR*(FM*SAO)) * (ET*N_Replen) * (1- (1-SE)(Freq_O-to-M/N_Replen)) Where: OR = object residue loading (e.g., mg ai/cm2) FM = fraction of object mouthed SAO = surface area of object (e.g., cm2) ET = exposure time (e.g., hrs) N_Replen = object loading replenishments (e.g., # / hr) Freq_O-to-M = object-to-mouth contact frequency (e.g., # / hr) SE = saliva extraction (fraction) Health Effects Division Office of Pesticide Programs
Hand-to-mouth Exposure Exposure = ((HR*(FM*SAH)) * (ET*N_Replen) * (1- (1-SE)(Freq_H-to-M/N_Replen)) Where: HR = hand residue loading (e.g., mg ai/cm2) FM = fraction of hand mouthed SAH = surface area of hand (e.g., cm2) ET = exposure time (e.g., hrs) N_Replen = hand loading replenishments (e.g., # / hr) Freq_H-to-M = hand-to-mouth contact frequency (e.g., # / hr) SE = saliva extraction (fraction) Health Effects Division Office of Pesticide Programs
Registration Process Pesticide Registrant EPA Chemical Review Manager Scientific Review/ Risk Assessment Evaluate Human Toxicity Risk Management Human Exposure Assessment Environmental Assessment Health Effects Division Office of Pesticide Programs
Future Directions • Incorporating peer-review comments from Scientific Advisory Panel and other stakeholders • Continue to revise SOPs as new data and information becomes available • Particularly interested in testing protocols that can help standardize data reporting Health Effects Division Office of Pesticide Programs
Resources • Residential SOP Scientific Advisory Panel Peer-Review, Background Materials, and Public Comments • Available at www.regulations.gov. Search: “EPA-HQ-OPP-2009-0516”. • Overview on Pesticide Registration Review Process • http://www.epa.gov/oppsrrd1/registration_review/reg_review_process.htm • Purdue Pesticide Programs Publications • Pesticides and the Label • http://www.btny.purdue.edu/Pubs/PPP/PPP-24/ppp24.html • Pesticides and Human Health Risk Assessment • http://www.btny.purdue.edu/Pubs/PPP/PPP-48.pdf Health Effects Division Office of Pesticide Programs
Questions Health Effects Division Office of Pesticide Programs