Overview of EPA s Approach for Indirect Dietary Exposure Assessment of Residential and Commercial Food Contact Antimicrobial Products Eleventh Antimicrobial Workshop March 10-11, 2015 Kristin M. Rury, MPH Julie L. Van Alstine, MPH Donald B. Wilbur, Antimicrobial Dietary Team Leader Health Effects Division Office of Pesticide Programs U.S. Environmental Protection Agency
Discussion Outline What is the HED-AD Dietary Support Team? Overview of Dietary Exposure Assessment Overview of Tiered Approach to Dietary Exposure Assessment Commercial Settings Residential Settings Conclusions 2
EPA s Office of Pesticide Programs HED-AD DST The Health Effects Division-Antimicrobials Division Dietary Support Team (HED-AD DST) conducts dietary exposure assessments for antimicrobial pesticides The team is comprised of OPP scientists with backgrounds in dietary exposure assessment 3
Dietary Exposure Assessment Approach Evaluate food consumption patterns and residue concentrations that lead to highest potential for exposure Assessments range from simple to complex, but based on same general exposure algorithm: Consumption X Residue = Dietary Exposure Can incorporate refinements into the exposure assessment to reflect more realistic assumptions Use NHANES/WWEIA consumption data 4
What Type of Assessment is Required? Commercial Assessment: Food-handling establishment, public eating establishment, food processing plant, etc. Residential Assessment: Strictly residential settings (e.g., kitchen counter tops, food-contact surfaces in homes, etc.) 5
Commercial Food Contact Assessments Use a tiered approach for commercial assessments: Tier 1A: Default Conservative Assumptions Tier 1B: First Refinement (Residue Adjustment Factor) Refined Assessments: Under development 6
Tier 1A and Tier 1B Commercial Assessments Tier 1A Assumptions: 1 mg/cm² of product residue is present on the surface (FDA, 1993) The surface work area is currently 4000 cm 2 Value is under review to ensure this is consistent with current practices and existing FDA methodology 100% of residues transfer from the surface into food consumed by each individual daily 100% of food contacts treated surfaces Tier 1B Incorporates: Residue adjustment factor(s) such as: Reductions in the percent transfer of residues to food Reductions in surface residues 7
Commercial Tier 1A and Tier 1B Assessments EEEEEEEEEEEEEEEE = AAAAAA SSSS FF BBBB =? mg/kg/day AoS= Active Ingredient Residue on Surface (mg/cm 2 ) SA = Area of Treated Surface (cm 2 ) F = Fraction Transferred (%) BW = Body Weight (kg) Current Commercial SA * = 4000 cm 2 * Value is under review to ensure this is consistent with current practices 8
Refined Commercial Assessments A commercial model has been developed by the American Chemistry Council (ACC) Biocides Panel Acute and chronic assessments Uses NHANES/WWEIA consumption data Calculates potential dietary exposures All food processing equipment and utensils, including dairy All food processing equipment and utensils, excluding dairy Currently being reviewed by EPA (HED/CEB) in consultation with FDA 9
Residential Food Contact Assessments Use a tiered approach to calculate indirect dietary exposure estimates resulting from the use of antimicrobial products in residential environments: Tier 1A: Default Conservative Assumptions Tier 1B: First Refinement (Residue Adjustment Factor) Tier 2: Food Consumption Model (General Refinement) Tier 3: Food Consumption Model (with Chemical-Specific Refinements) Tier 4: Advanced Exposure Assessment Model(s) 10
Tier 1A and Tier 1B Residential Assessments Tier 1A Assumptions: 1 mg/cm² of product residue is present on the kitchen surface (FDA 1993) The kitchen surface work area is 2000 cm 2 100% of residues transfer from the countertop into food consumed by each individual daily 100% of solid food contacts treated surfaces Tier 1B Incorporates: Residue adjustment factor(s) such as: Reductions in the percent transfer of residues to food Reductions in surface residues 11
Residential Tier 1A and Tier 1B Assessments EEEEEEEEEEEEEEEE = AAAAAA SSSS FF BBBB =? mg/kg/day AoS= Active Ingredient Residue on Surface (mg/cm 2 ) SA = Area of Treated Surface (cm 2 ) F = Fraction Transferred (%) BW = Body Weight (kg) Residential SA = 2000 cm 2 12
Tier 2 and Tier 3 Residential Assessments Use the Indirect Dietary Residential Exposure Assessment Model (IDREAM): Incorporates parameters that are specific to residential uses of hard-surface disinfectants and cleaners Incorporates food consumption and preparation patterns in the home Categorizes foods based on physical form and likelihood of residential countertop contact Uses food consumption data from the 2005-2010 cycles of the USDA s NHANES/WWEIA Tier 3 assessments incorporate chemical-specific refinements 13
Introduction to IDREAM Model (Residential) Developed by the American Chemistry Council Biocides Panel in response to a need identified by EPA s Antimicrobials Division A revised version was developed and submitted to EPA in December 2013 EPA has reviewed the final version and determined that it is appropriate for regulatory use The HED-AD DST is using this model and is in the process of developing a manual Only for assessments of hard-surface antimicrobial products in residential settings Cannot be used to assess exposures for other settings (i.e., soft surfaces, commercial settings, etc.) 14
Introduction to IDREAM Model (cont.) Inputs include Chemical name Percent active ingredient in the product Toxicity information (acute and/or chronic population adjusted dose; apad/cpad) Outputs include Exposure levels (mg/kg bw/day) Risk (% PAD occupied) 15
Example of IDREAM Residential Tier 2 Assessment 16
IDREAM Tier 3 Residential Assessment Uses the same methodology and algorithms as a Tier 2 assessment, but incorporates refinement data: Refined consumer behavior data Chemical-specific residue data Chemical-specific residue transfer efficiency (RTE) data Example: Food Category Default RTE Chemical-Specific RTE Bread 20% 10% Meat 80% 50% 17
Example IDREAM Residential Tier 2 vs Tier 3 Assessment 18
Tier 4 Assessments Most highly refined assessments Typically require the generation of substantial data and construction of appropriate algorithms to estimate exposures Completed on a case-by-case chemical- or product-specific basis 19
Conclusions EPA uses a tiered approach for estimating dietary exposure due to the use of antimicrobial products on food-contact surfaces in residential and commercial settings Tier 1A/1B assessments are unrefined Commercial model for refined assessments is currently being reviewed by EPA Use IDREAM model for Tier 2/3 refined residential assessments IDREAM residential manual is in development Models will be publically available when review is complete 20
Contact Information For further questions related to dietary exposures and assessments, contact: Kristin M. Rury, MPH, Biologist Health Effects Division Office of Pesticide Programs U.S. Environmental Protection Agency rury.kristin@epa.gov Julie L. Van Alstine, MPH, Environmental Health Scientist Health Effects Division Office of Pesticide Programs U.S. Environmental Protection Agency vanalstine.julie@epa.gov Donald B. Wilbur, Chemist, Antimicrobial Dietary Team Leader Health Effects Division Office of Pesticide Programs U.S. Environmental Protection Agency wilbur.donald@epa.gov 21
Questions? 22
Additional Slides 23
USDA s What We Eat In America National food survey conducted as part of the National Health and Nutrition Examination Survey (NHANES) Nationally representative design Replacement survey for the Continuing Survey of Food Intake by Individuals (CSFII) Contains food consumption data for ca. 7,000 foods Captures water consumption data Collected on a two-year cycle Approximately 10,000 individuals per cycle Oversampling of various subpopulations Data collected on two non-consecutive days of 24-hour dietary recall using validated USDA method Limitations: Seasonal, Regional, Longitudinal Considerations Additional Information: http://www.ars.usda.gov/services/docs.htm?docid=13793 24