兰州市区典型持久性有机污染物的生态风险评价

以兰州市区为研究区域,以屈(Chrysene)和2,3,7,8-四氯二苯-p-二噁英(2,3,7,8-TCDD)两种典型持久性污染物为例,应用RAIDAR(Risk Assessment Identification And Ranking)模型对它们在研究区域环境中的潜在生态风险进行模拟计算和评价,并根据LevelⅡ和LevelⅢ的计算结果对污染物按风险进行归类。模拟结果表明:以全部排放到大气计算,且以非生物介质中的阈值分析时,2,3,7,8-TCDD的RAF(Risk Assessment Factor)值是1940,归为A类化合物,CHr的RAF值为10.8,归为B类化合物。将RAIDAR模型用于污染物的风险评价,以筛选出那些急需进行评价的污染物作进一步的分析是很有研究意义的。

Ecological Risk Assessment of Typical POPs in Lanzhou City

RAIDAR model was used to simulate and estimate the potential ecological risk of chrysene and 2,3,7,8-TCDD in Lanzhou City,which were typical persistent organic pollutants.The model could also bin substances into categories of similar probable risk prior order based on simple Level Ⅱ or more complex Level Ⅲ fate calculations.The simulation results showed that if all pollutants were discharged into atmosphere and objective endpoints were used to estimate the risk,2,3,7,8-tetrachlorodibenzo-p-dioxin which had a risk assessment factor (RAF)of 1940 was binned into categories of A according to classification standard.However,chrysene which had a RAF of 10.8 was binned into categories of B.It was important to use RAIDAR model for risk assessment of pollutants,in order to filter out those pollutants which were urgently needed for further evaluation.