土壤中多氯联苯的综合污染指数评价方法研究

借鉴综合污染指数的概念,引入加拿大环境理事会制订的土壤中多氯联苯(PCBs)标准指标.建立了PCBs污染的毒害性分污染指数(TPI)、持久性分污染指数(PPI)和生物累积性分污染指数(BPI)加权计算的综合污染指数(IPI)评价方法以及各污染指数的相关表达式,确定了土壤环境中PCBs的毒害性转换系数(Ti)、持久性转换系数(Pi)和生物累积性转换系数(Bi).利用建立的土壤中PCBs的综合污染指数评价方法定量评价了现代黄河三角洲地区土壤中的PCBs污染现状,22个采样点的PCBs污染的IPI值在1.1-531.7之间,整个现代黄河三角洲地区的PCBs污染现状属轻度污染.该评价体系综合地考虑了PCB8同系物间的环境行为差异,较现有的PCBs总量评价方法更科学合理,在持久有机污染物(POPs)的污染评价方面具有推广价值.

Integration Pollution Index (IPI) Method for Evaluation of Polychlorinated Biphenyls (PCBs) Pollution in Soil

An integration pollutant index (IPI) evaluation method with proportional addition of toxicity pollution sub-index (TPI), persistence pollution sub-index (PPI), and bio-accumulation pollution sub-indexes (BPI) for polychlorinated biphenyls (PCBs) pollution in soil was set up for the first time by referring to the conception of IPI and introducing the standard value series of total PCBs employed by national guideline and standards office, Canada. The relevant expressions for pollution indexes were defined; three transformation coefficients for PCBs toxicity (T_i), persistence (P_i), and bio-accumulation (B_i) pollution were apportioned, too. Then, by the application of the evaluation method, the IPIs for PCBs pollution evaluations in 22 soil sample stations in the Yellow River Delta and a background sample were accomplished successfully, the quantification results were in range of 1.1-531.7, the qualification result was that the Yellow River Delta was slightly polluted by PCBs. This integrated evaluation model considered the characteristic differences between PCBs congeners and was more scientifical and comprehensive than current method, and should be employed in evaluations of persistent organic pollutants (POPs).