McKone T E
University of California, Davis.
Risk Anal. 1994 Aug;14(4):449-63. doi: 10.1111/j.1539-6924.1994.tb00263.x.
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.
本文提出了一个关于食用本地种植食物的通用模型，该模型与蒙特卡洛分析一起使用，以确定变异性（A类不确定性）和真实不确定性（B类不确定性）对剂量-浓度比预测中总方差的相对贡献。尽管将暴露输入分类为不确定或可变在某种程度上是主观的，但食物消费率和暴露持续时间被判定其预测方差主要由年龄、收入、文化和地理区域等个体间的变异性主导。而生物转移因子和分配因子在很大程度上是涉及不确定性的输入。以摄入假定受六氯苯（HCB）和苯并(a)芘（BaP）污染的水果、蔬菜、谷物、乳制品、肉类和土壤作为案例研究，使用蒙特卡洛分析来探究不确定性和变异性对食用本地种植食物人群中潜在剂量估计分布的总方差的相对贡献。研究发现，当指定土壤浓度时，HCB剂量-浓度比的方差同样归因于不确定性和变异性，而对于BaP，这些比率的方差主要由真实不确定性主导。
