污染场地健康风险评价中多介质模型的优选研究

综合考虑了参数不确定性、模型不确定性对风险评价结果可信度的影响差异和国内实际污染场地健康风险评价中对已有模型的不当选择可能带来的负面效应,提出相对于参数不确定性的控制,针对目标情景的适当模型选择应成为提高风险评价结果可信度的更重要环节.本研究选取了模型理论架构上符合案例情景的美国环境保护署研发的3MRA、MMSOILS和美国劳伦斯伯克力国家实验室研发的CalTOX 3个被广泛使用的污染场地健康风险评价多介质模型,并与蒙特卡洛模拟相结合,载入污染厂址案例,并对特定受体进行了风险评价,由此定量分析了参数不确定性和模型选择不确定对评价结果可信度的影响程度,并通过对比3个模型的内在架构分析了不确定性的可能来源,最后总结提出了“6步综合评价模式”,该模式能有效提高污染场地健康风险评价的可信度及经济可行性.

Optimized environmental multimedia model screening for health risk assessment of contaminated sites

Through the considerable improvement of risk assessment system,uncertainty remained a primary threat to the confidence level of risk assessment.Under the primary definitions of uncertainty in environmental risk assessment home and abroad,owing to the realistic and theoretical limit,choosing the relatively suitable model was considered to be much more important step to the risk assessment process concerning the reduction of uncertainty.In particular,model uncertainty probably made a much bigger effect than that of parameter uncertainty.This study quantified the effects of different sources of uncertainty and developed a screening procedure to choose the relatively suitable model on basis that 3MRA,MMSOILS and CalTOX models combined with Monte Carlo simulation were applied to the same contaminated site and the typical receptor.The 6-steps comprehensive assessment procedure would be an important reference to future health risk assessment of contaminated sites.