In the table below, arithmetic mean, standard error of mean and 1 st to 99 th percentiles were given for two specific subpopulations from the UMDES:

Transcription

1 UMDES Response to data request from Lesa Aylward, Ph.D. 1/12/2016 The UMDES team received a request (dated 11/26/2015) from Lesa L. Aylward (attached). We were asked to calculate unadjusted Average Daily Dose (ADD, in pg TEQ/kg-day) from consumption of game (whitetail deer, venison, wild turkey, pheasant, grouse, quail, woodcock, wild duck, goose, squirrel, or wild rabbit) taken in the Tittabawassee River floodplain in the last 5 years and report weighted population statistics for two specific subpopulations from the UMDES. In the table below, arithmetic mean, standard error of mean and 1 st to 99 th percentiles were given for two specific subpopulations from the UMDES: TR Floodplain= Resident in the Tittabawassee River floodplain Other Midland= Resident in the nearby areas (designated in the UMDES survey as Midland Plume, Near-Floodplain, and Midland/Saginaw out of Floodplain) The mean ADD for people living in the Tittabawassee River floodplain is pg TEQ/kg-d with standard error pg TEQ/kg-d. The mean ADD for people living in Other Midland is pgteq/kg-d with standard error pg TEQ/kg-d. Statistics TR Floodplain Other Midland Mean Standard Error of mean st Percentile 0 0 2nd Percentile 0 0 3nd Percentile 0 0 4th Percentile 0 0 5th Percentile 0 0 6th Percentile 0 0 7th Percentile 0 0 8th Percentile 0 0 9th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile 0 0

2 Statistics TR Floodplain Other Midland 21st Percentile nd Percentile rd Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile st Percentile nd Percentile rd Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile st Percentile nd Percentile rd Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile st Percentile nd Percentile rd Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile 0 0

3 Statistics TR Floodplain Other Midland 61st Percentile nd Percentile rd Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile st Percentile nd Percentile rd Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile st Percentile nd Percentile rd Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile st Percentile nd Percentile rd Percentile th Percentile th Percentile th Percentile th Percentile th Percentile th Percentile

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5 -----Original Request from Lesa Aylward, Ph.D. 11/26/ Data Analysis Request for UMDES Estimation of Exposures to Polychlorinated Dibenzo-p-Dioxins and Dibenzofurans (PCDD/Fs) Due to Consumption of Game from the Tittabawassee River Floodplain I. Introduction This letter provides information regarding a request for analysis of questionnaire data collected during the University of Michigan Dioxin Exposure Study (UMDES). Specifically, we are requesting a calculation of the population distribution of estimated aggregate exposure from consumption of game taken in the Tittabawassee River (TR) Floodplain. This request covers two specific subpopulations from the UMDES: 1. Persons resident in the TR Floodplain; and 2. Persons resident in the nearby areas (designated in the UMDES survey as Midland Plume, Near- Floodplain, and Midland/Saginaw out of Floodplain), considered collectively as one group. For each of the two subpopulations identified above, we would like to evaluate the distribution of estimated PCDD/F TEQ exposure due to consumption of wild game meals from game taken from the TR Floodplain. This analysis depends on three main elements: UMDES data on the categories of game and numbers of meals in each category consumed from the TR Floodplain by participant; NHANES data on the size of meals of game; and Collected data on the PCDD/F TEQ tissue concentration for each type of game meat. These elements can be combined to estimate, for each participant in the survey, an unadjusted average daily dose (ADD) of PCDD/F TEQ from each game category and summed across categories. These participant-specific ADD estimates can then be used to generate a population distribution of intakes from wild game consumption, and this distribution can be considered in conjunction with and adjusted for other factors including potential loss of contaminants due to cooking, anticipated changes in game tissue concentrations due to remediation steps taken in the TR Floodplain, and other factors, in order describe the population distribution of PCDD/F TEQ exposure from game consumption from the TR Floodplain. The following sections provide specific information on each of these elements and on the algorithm we suggest for calculation of exposure. II. Game Categories The UMDES Questionnaire Section G Current Diet contains a series of specific questions directed at eliciting participants recollection of game meals from anywhere, and specifically, from animals taken in the TR Floodplain and the Saginaw River/Bay Floodplain. For the purposes of this request, we focus on the data regarding consumption of meals of game taken from the TR Floodplain.

6 Several categories of game were covered by a series of two-part questions. For each species category, participants were first asked if they had consumed that species taken from the TR Floodplain in the last five years. If the participant answered yes, the participant gave an estimate of the total number of meals taken from the TR Floodplain that they consumed over that 5-year period for that species group. The categories covered by these two-part questions (and the question numbers dedicated to the TR Floodplain-related consumption) are: 1. Whitetail Deer/Venison (referred to from here forward as Venison ) [Question G6d] 2. Wild Turkey, Pheasant, Grouse, Quail, or Woodcock ( Turkey ) [Question G7b] 3. Wild Duck or Goose ( Duck ) [Question G8a] 4. Squirrel or Wild Rabbit ( Squirrel ) [Question G9a] 5. Other [Question G10b] The Other category included a wide variety of possible game consumption. The question was worded as follows: G10 asked participants whether they had ever eaten any other game meat not already mentioned such as Raccoon, Opossum, Groundhog, Woodchuck, Muskrat, Wild Turtle or Frog during the last 5 years. Participants reported alligator, antelope, bear, beaver, buffalo, caribou, elk, frog, goat, lion, moose, mule deer, muskrat, porcupine, raccoon, rattlesnake, turtle and woodchuck. While approximately 6% of the overall survey population reported ever eating a meal from ANYWHERE that falls into the Other category, the number reporting ever eating such meals taken from the TR floodplain was limited to two positive responses from the Out of Floodplain group: As a result, and given the lack of specific information on species included in those two positive responses, we do not include consumption of meals from the Other category in our request. III. Meal Sizes for Game Meals We have identified data from the US National Health and Nutrition Examination Survey (NHANES) relevant to estimating meal sizes for game meals. The three combined NHANES biennial cycles ( ; ; ) include detailed dietary survey data from between 25,000 and 30,000 surveyed individuals. The data include reported information on the amount of the food consumed per eating occasion for a wide variety of foods including venison, turkey, pheasant, quail, duck, goose, squirrel, and rabbit.

7 Data include reporting from individuals on their consumption of these species in many forms including as steaks or meat and as a component of dishes prepared with meat from the species, for example, as stew. The amount of game consumed in a given eating occasion was reported directly for foods such as venison steak, turkey breast, cooked rabbit or squirrel, or roasted duck. For foods such as stews, the full amount eaten was reported by the participants, and the standard NHANES recipe for the food code was used to calculate the amount of the game consumed on that eating occasion. We categorized all reported eating occasions for these foods into the four game categories described in Section II, and extracted meal size data for adults. Adult meal sizes for the four categories did not differ statistically among the four game categories. However, meal sizes for women (n=540) differed from those for men (n=510). We are providing the full matrix of reported meal sizes from the three biennials of NHANES data collected from 2007 to 2012 separately for men and women (Supplementary Material, Excel file). We ask that meal sizes for the calculations below be drawn randomly from the full NHANES dataset of reported game meal sizes by sex for each participant and game meal in the calculations (additional details are provided below). IV. Representative Tissue Concentrations Sampling of game collected in the TR Floodplain was conducted in 2003 and 2007 (Entrix 2004, 2007). Samples included deer, wild turkey, wild duck, squirrel, and rabbit, collected at several locations in the TR Floodplain. Tissues were analyzed for PCDD/F congeners, and TEQ concentrations were calculated using the 2005 WHO toxicity equivalency factors. Because many congeners were non-detected in various samples, imputation of values for non-detected congeners was required for calculating the PCDD/F TEQ. For this analysis, tissue concentrations for non-detected congeners were imputed using the Kaplan-Meier (KM) method (Helsel 2009). This approach has been endorsed by USEPA (2011; Appendix 4, see p. 105) in the context of calculating TEQ concentrations for datasets with significant proportions of congener non-detects. Concentrations of TEQ in various game tissues varied. For turkey and duck and goose, concentrations were influenced by whether tissues were analyzed with skin on or skin off. For the purposes of this analysis, we are providing the full set of data. We ask that for each meal calculation a value be selected from the full distribution of measured values for the appropriate game category (provided as an Excel file as Supplemental Material). For meals of fowl species, we ask that question G7a of the UMDES survey be consulted. Question G7a asked participants whether they had eaten the skin of the Wild Turkey, Pheasant, Grouse, Quail, or Woodcock during the last 5 years. For the purposes of the exposure assessment, it will be assumed that answering Yes to this question reflects a preference for consuming the skin from fowl species and is applicable to all of their meals from the two categories with fowl. Thus, based on the answer to this question, we request that concentrations be drawn randomly from the skin-on or skin-off dataset for both the turkey category and the duck/goose category, as appropriate. These tissue concentrations from raw game samples represent pre-remediation conditions, but are used here as an initial basis for estimating exposures.

8 V. Calculation Approach and Algorithm The basic approach to calculating exposure from the recalled number of game meals over the last five years for a participant and specific game resource is as follows: 1 ADD = BW M i C i Where ADD is average daily dose in pg TEQ/kg-d, M i is the meal size for that meal in g drawn randomly from the appropriate sex-specific distribution, C i is the tissue concentration in pg TEQ/g for that meal drawn randomly from the appropriate game concentration dataset for that species, N is the number of meals of that species reported as being consumed from the TR Floodplain for the five year period, and BW is the participant-specific bodyweight. Total exposure from wild game consumption from the TR Floodplain for each participant is calculated by summing this species-specific calculation over the four categories of game as discussed in Section II above. These calculations do not include the impact of any reduction in tissue concentrations that may occur during cooking. Appropriate reductions to calculated exposures will be applied after uncooked exposures based on the raw tissue concentrations are calculated and reported. The algorithm for calculating total exposure due to game meal consumption in pseudocode is presented in more detail in Box 1. N i=1 VI. Requested Output We are requesting output that describes the population distribution of unadjusted average daily dose (ADD) due to game meals for each of the two subpopulations described above in Section I. These distributions of unadjusted ADD will be considered in conjunction with and adjusted for other information related to factors affecting exposure including potential changes in game tissue concentrations occurring following remediation activities, potential reductions in raw tissue concentrations that may occur upon cooking, and other factors, in order to facilitate a probabilistic assessment of exposures for the two subpopulations due to consumption of game taken in the TR Floodplain in the post-remediation landscape. For each of the two populations specified in Section I, please report weighted population statistics for the calculated unadjusted Average Daily Dose (ADD pg TEQ/kg BW-d) from game consumption as follows: Arithmetic Mean, Standard error (SE) of mean, and 1 st to 99 th percentiles, by each individual percentile (99 values).

9 Box 1: Pseudocode of calculation algorithm to estimate total exposure to TEQ from game consumption for each participant based on preremediation tissue concentrations in raw samples of game from the Tittabawassee River Floodplain, NHANES data on meal sizes, and UMDES-reported consumption of game meals. For each subpopulation of interest: MS Floodplain, or Grouped (Near FP, Out of FP, and M/S Plume) For each participant within that subpopulation, j=1 to J If Participant j said Yes to G7a C Tky=value drawn from Turkey skin-on dataset C Duck=value drawn from Duck skin-on dataset Else C Tky=value drawn from Turkey skin-off dataset C Duck=value drawn from Duck skin-off dataset Endif For each game category (Venison, Turkey, Duck, Squirrel, as defined in Section II) For each meal, i=1 to N, where N is the total number of meals in that game category for that person: **Randomly draw a meal size M (from appropriate sex-specific NHANES dataset) **Randomly draw a game tissue concentration C (from correct game tissue concentration dataset) **Calculate exposure from that meal as M*C

10 VII. References ENTRIX (2004). Evaluation of PCDDs and PCDFs in wild game taken from the floodplain along the Tittabawassee River. Prepared by ENTRIX, Inc., East Lansing, Michigan. Prepared for The Dow Chemical Company, Midland, Michigan. June ENTRIX Analytical report for wild game sampled from the Tittabawassee and Saginaw Rivers in support of the Human Health Risk Assessment. Prepared for The Dow Chemical Company, Midland, Michigan. ENTRIX, Inc., East Lansing, MI Helsel, D. Summing nondetects: Incorporating low-level contaminants in risk assessment. Integrated Environmental Assessment and Management 6(3): USEPA Uniform Federal Policy Quality Assurance Project Plan Template for Soils Assessment of Dioxin Sites. Available at: QAPP%20Template.pdf