Session on Assessment of Food Exposure

1. Session on Assessment of Food Exposure

2. Food Exposure William O. Smith, Ph.D. Chemist Health Effects Division Office of Pesticide Programs

3. Outline of Presentation • Exposure Input parameters • Residues (USDA/PDP & FDA/CFSAN) • Consumption (USDA CSFII 1994-96/1998) • Residue Manipulations • Index Equivalent Residues (RPF method) • Probabilistic Exposure/Risk Assessment

4. Sources of Residue Data • USDA Pesticide Data Program (PDP) • http://www.ams.usda.gov/science/pdp • FDA Center for Food Safety & Applied Nutrition • http://www.cfsan.fda.gov/~lrd/pestadd.html • Pesticide Residue Monitoring Program • Total Diet Study (TDS)

5. OPs Included in Current Food Assessment acephate, azinphos methyl, chlorpyrifos, chlorpyrifos-methyl, disulfoton, diazinon, dichlorvos, dimethoate, ethoprop, fenamiphos, malathion, methidathion, methamidophos, mevinphos, oxydemeton-methyl, methyl parathion, phorate, phosolone, phosmet, pirimiphos methyl, terbufos, & tribufos

6. PDP Foods Included in Assessment Apples Apple Juice Bananas Broccoli Celery Cantaloupe Carrots Sweet Corn Cucumbers Corn Syrup Cherries Rice Green Beans Grapes Grape Juice Lettuce Milk Oats Oranges Orange Juice Peaches Pears Nectarines Pineapple Potatoes Bell Peppers Strawberries Sweet Potatoes Soybean Spinach Sweet Peas Tomatoes Wheat Winter Squash Poultry Peanut Butter

7. Foods Based on Translated PDP Data Rutabagas Turnips Various leafy greens Brussels sprouts Cabbage Cauliflower Melons (other than cantaloupe) Pumpkins Squash-summer Eggplant Pepper(other than green) Citrus (other than orange) Apricots Plums/Prunes Rye Beets-garden Horseradish Parsnips Radishes

8. Foods Based on FDA Monitoring Data • Eggs • Assume negligible based on FDA monitoring data • Seafood • Assume negligible based on FDA monitoring data • Meat from Beef, Pork, Sheep & Goats • Used maximum residues found in FDA/TDS

9. Foods Assumed Negligible Contributors • Sugarcane, Sugar Beet & Maple • Molasses, syrup & sugar • Assume negligible residues because… • Highly processed/refined • No residues in sugar or pancake syrup analyzed by FDA/TDS • No residues in corn syrup analyzed by PDP

10. The Proportion of the Diet of Children (3-5) Covered in the Cumulative AssessmentSource of Residue Estimate% of Diet PDP (RACs & processed) 85.7 Translation of PDP 1.3 FDA 6.3 Assumed negligible 3.1 Not included 3.6

11. The Proportion of the Diet of Children (3-5) Covered in the Cumulative Assessment • Top 30 foods are included in this assessment • Top 95% of Diet=56 foods • 52 of 56 top foods included

12. Foods Not Included in Preliminary Assessment • Not expected to impact significantly on assessment • Many are highly processed or blended foods • Infrequently detected residues and/or low levels

13. Exposure=Residue X Consumption Cumulative Dietary Exposure MOE=Point of Departure/Exposure Cumulative Residues

14. Relative Potency Factor Method of Estimating Cumulative Residues Converted chemical specific residues on food samples to a common residue Index Equivalent Residue (Residue)

15. Calculation of Cumulative Residues Residue: PDP residue data by sample PF: Processing factor (if applicable) RPF: Relative potency factor ResidueIE=Residue X PF X RPF Cumulative ResidueIE=S ResidueIE (per PDP sample)

16. Residue Inputs for Cumulative Assessment Distributions of cumulative residues OR Average cumulative residues for highly blended foods

17. Cumulative Dietary Exposure Exposure=Residue X Consumption CSFII 94-96/98

18. CSFII 1994-96/1998 • Intakes of individuals residing in U.S. • 20,607 individual participants interviewed over two discontinuous days (~3-10 days apart) • 1998 Supplemental Children’s Survey • 5,559 additional children • Birth through 9 years old

19. CSFII 1994-96/1998 • The 1994-96/1998 CSFII significantly increases the number of children in the survey compared to the 1989-91 survey data currently being used by OPP

20. Comparison of Number of 1-day and Complete Intakes, by Children’s Age Group 1994-96/1998 vs. 1989-91 CSFII

21. Populations Groups Assessed • Separate assessments were based on survey information on the following age groups: • Children 1-2 years old • Children 3-5 years old • Adults 20-49 years old • Adults 50+ years old

22. Exposure Assessment Models • DEEM™ and Calendex™ were used to estimate cumulative food exposure and risk • The use of Calendex™ and related issues will be discussed next by David Miller

23. DEEM Model • Dietary Exposure Evaluation Model: DEEM-FCID™ • Probabilistic (Monte-Carlo) procedure • Input: • Distributions for consumption • Distributions or point estimates for residue concentrations • Output: • Distribution of one-day dietary exposures • Distribution of associated risks, i.e., MOEs

24. Dietary Exposure Evaluation Model DEEM-FCID™ • Uses EPA's Food Commodity Intake Database • Commodity definitions are based on EPA's Food Commodity Vocabulary • Recipes for relating foods consumed to raw commodities are publicly available

25. 10 100 MOE 1000 10000 100000 1000000 0 10 20 30 40 50 60 70 80 90 100 Percentile of per-capita Days Children 1-2 Children 3-5 Adults 20-49 Adults 50+ Preliminary Cumulative Food Exposure

26. 10 100 MOE 1000 Adults 50+ 10000 90 91 92 93 94 95 96 97 98 99 100 Percentile of per-capita Days Children 1-2 Children 3-5 Adults 20-49 Preliminary Cumulative Food Exposure-Upper Portion of Distribution

27. Preliminary Cumulative Exposure Assessment Margin of Exposure (MOE) at Upper-End of Distribution Percentile 95th 90th 97.5th 99th 99.5th 99.9th Children 1-2 800 454 280 160 108 51 Children 3-5 994 562 348 196 133 62 Adults 20-49 2415 1280 755 415 281 127 Adults 50+ 2321 1228 720 393 264 125 MOE = POD/exposure; POD = 0.08 mg/kg body wt/day

28. Final Preliminary • Further refinements to inputs • Interpretation of results Work to be completed…

29. Potential Effects of Input Assumptions & Refinements on the Assessment • Translation of PDP residue data to other foods • Use of processing factors to estimate residues in processed food forms (cooked, dried, juices, etc.)

30. Effect of Translation of PDP Data MOEs for Children 1-2 at Selected Points in the Exposure Distribution Mean 95th 99th 99.5th 99.9th Full Assessment 2001 457 160 110 52 Only PDP Foods 2082 470 165 114 53 MOE=POD/exposure; POD=0.08 mg/kg body wt/day

31. Mean 95th 99th 99.5th 99.9th Full Assessment 2001 457 160 110 52 No OP/Baby Food 2087 471 164 112 52 Effect of Baby Foods MOEs for Children 1-2 at Selected Points in the Exposure Distribution MOE=POD/exposure; POD=0.08 mg/kg body wt/day

32. Mean 95th 99th 99.5th 99.9th Full Assessment 2001 457 160 110 52 No Extrapolations 4895 988 293 188 77 Impact of Processing & Translations MOEs for Children 1-2 at Selected Points in the Exposure Distribution MOE=POD/exposure; POD=0.08 mg/kg body wt/day

33. 1 Full Assessment 10 PDP-only MOE 100 No Extrapolation 1000 10000 85 87 89 91 93 95 97 99 Percentile of Exposure Cumulative Exposure Distribution-Effect of Translations and Extrapolation of Data

34. Effect of Older Data on Assessment • PDP foods analyzed 1994-2000 • One to 5 years PDP data per food • Evaluating later data to see if they better represent current use practices

35. Mean 95th 99th 99.5th 99.9th Full Assessment 2001 457 160 110 52 2 Years Data 2205 503 181 125 58 Effect of Older Data on the Assessment MOEs for Children 1-2 at Selected Points in the Exposure Distribution MOE=POD/exposure; POD=0.08 mg/kg body wt/day

36. Effect of Older Data on Assessment • Analysis not complete • Complex factors • Multiple distributions representing different segments of time

37. Analysis of Contributors to the Exposure Distribution • DEEM Critical Exposure Commodity Analysis identifies major contributors to exposure • Currently analyzing the top food contributors & the factors related to their contributions • Chemical residues (potency, frequency, levels) • Sampling details (origin & date of sample)

38. Analysis of Contributors to the Exposure Distribution • Foods A, B, and C • Highest contributors to exposure between 99.8th & 100th percentile • Examined impact of removal of OP residues from all forms of each of these foods from the cumulative assessment

39. 50th 95th 99th 99.5th 99.9th Full Assessment 16606 457 160 110 52 Minus Food A 47676 651 222 149 63 Minus Food B 19920 495 178 121 56 Minus Food C 60737 652 192 126 55 Minus A & B 57494 727 255 174 75 Minus A,B,& C 149770 1666 428 268 105 Impact of Foods A, B, & C on Assessment MOEs for Children 1-2 at Selected Points in the Exposure Distribution

40. 10 100 Preliminary No Food A MOE No Food B No Food C 1000 No Foods A, B,or C 10000 85 90 95 100 Percentile of Exposure Impact of Foods A,B, & C on Assessment

41. 50th 95th 99th 99.5th 99.9th Full Assessment 1 1 1 1 1 Minus Food A 2.9 1.4 1.4 1.4 1.2 Minus Food B 1.2 1.1 1.1 1.1 1.1 Minus Food C 3.7 1.4 1.2 1.2 1.1 Minus A & B 3.5 1.6 1.6 1.6 1.4 Minus A,B,& C 9 3.7 2.7 2.4 2 Impact of Foods A, B, & C on Assessment Ratios of MOEn/MOEfull assessment

42. Interpretation of The Food Risk Results • PDP residue data cover the major food consumption items • Further refinements of PDP data not likely to drastically alter the results at the higher end of the exposure distribution • Complex factors are contributing to the exposure distribution

43. Calendar-Based Exposure Assessment • Calendex™ was used to estimate cumulative exposure from food, water, and residential uses as a series of daily exposure distributions for a year • This time-series food exposure assessment and related issues will be discussed next by David Miller

44. Time-Frame Considerations David Miller Chemist (USPHS) Health Effects Division

45. Outline of Presentation • Introduction/Background information • DEEM(FCID)™ vs. DEEM(FCID)/Calendex™ • Time-Frame Considerations • Modes in which Calendex™ can be used for a cumulative risk assessment • Consecutive daily estimates • Rolling (or sliding) time-frame • Strengths and limitations of these modes • Questions for the SAP

46. Points to Remember… • Presentation will not review step-by-step mechanics of DEEM(FCID)/Calendex™ algorithms: • DEEM/Calendex™ reviewed in previous SAPs • Presentation concentrates on exposure through food • Principles apply to all routes • No decision has been made on an appropriate MOE or threshold percentile for regulation

47. Introduction • DEEM(FCID)/Calendex™ provides a probabilistic assessment of exposures through food, water, and residential pathways • DEEM(FCID)/Calendex™ incorporates concept of a Calendar to evaluate aggregate or cumulative exposures • Time-based approach • Calendar-based approach looks at each individual day of the year • Calendar-based approach allows appropriate “temporal matching” of exposures through food, drinking water, and residential pathways • Temporal aspect of exposure important for OP’s due to expected seasonal use-patterns

48. Introduction • Calendex™ uses probabilistic techniques to appropriately combine exposures from the food, water, and residential pathways in a manner which incorporates: • probabilities of exposure, • use and application practices, • human activity patterns, • etc. • and considers their associated seasonality and timing • Result is a collection (or distribution) of aggregate exposures (food, residential, and drinking water combined) for each day of the year for the relevant region These exposures can be plotted as a “time-line” or profile of daily exposures for any given percentile in the distribution

50. How Does DEEM(FCID)/Calendex™ differ from DEEM(FCID)™? • DEEM(FCID)™ analysis assesses exposure from food alone without respect to timing/seasonality issues • Randomly matches reported food consumption, by individual, with residue data • No time component • Result is a single distribution of exposures and a single-valued estimate of risk at any given percentile of exposure