Uncertainty and variability in human exposures to soil contaminants through home-grown food: a Monte Carlo assessment.
This paper presents a general model for exposure to homegrown foods that is used with a Monte Carlo analysis to determine the relative contributions of variability (Type A uncertainty) and true uncertainty (Type B uncertainty) to the overall variance in prediction of the dose-to-concentration ratio. Although classification of exposure inputs as uncertain or variable is somewhat subjective, food consumption rates and exposure duration are judged to have a predicted variance that is dominated by variability among individuals by age, income, culture, and geographical region. Whereas, biotransfer factors and partition factors are inputs that, to a large extent, involve uncertainty. Using ingestion of fruits, vegetables, grains, dairy products, and meat and soils assumed to be contaminated by hexachlorobenzene (HCB) and benzo(a)pyrene (BaP) as cases studies, a Monte Carlo analysis is used to explore the relative contribution of uncertainty and variability to overall variance in the estimated distribution of potential dose within the population that consumes home-grown foods. It is found that, when soil concentrations are specified, variances in ratios of dose-to-concentration for HCB are equally attributable to uncertainty and variability, whereas for BaP, variance in these ratios is dominated by true uncertainty.
University of California, Davis.
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McKone
D000465:Algorithms; D000818:Animals; D001564:Benzo(a)pyrene / Q000009:adverse effects* / Q000032:analysis; D001682:Biological Availability; D001835:Body Weight; D004032:Diet; D002523:Edible Grain / Q000737:chemistry; D004531:Eggs / Q000032:analysis; D004781:Environmental Exposure; D005502:Food; D005504:Food Analysis; D005506:Food Contamination; D005638:Fruit / Q000737:chemistry; D006581:Hexachlorobenzene / Q000009:adverse effects* / Q000032:analysis; D006801:Humans; D008460:Meat / Q000032:analysis; D008954:Models, Biological; D015233:Models, Statistical; D009010:Monte Carlo Method; D018570:Risk Assessment; D012989:Soil Pollutants / Q000009:adverse effects* / Q000032:analysis; D013997:Time Factors; D014675:Vegetables / Q000737:chemistry
D012989:Soil Pollutants; D001564:Benzo(a)pyrene; D006581:Hexachlorobenzene