建设用地土壤优先管理有毒有害物质研究

A Study on Soil Priority Management of Toxic and Hazardous Substances for Development Land

筛选建设用地土壤的优先管理有毒有害物质,是开展土壤污染状况调查与风险评估、制定土壤质量标准和支撑土壤污染重点监管单位管理的依据。本文首先整合国内外多源数据进行土壤有毒有害物质筛选,然后通过化学排序并结合数理统计方法确立我国建设用地土壤优先管理的有毒有害物质名录。结果表明,通过国外与国内多源数据可以整合出886种候选土壤有毒有害物质,采用数据集合并的方法可筛选出123种应关注的土壤有毒有害物质。在此基础上,通过改进的化学排序系统,从人体毒性、暴露潜力、环境管理关注度和数据确定性4个层面,对土壤有毒有害物质进行参数化赋分与定量评价,并结合确定性得分结果,建立了含有99种物质的土壤优先管理有毒有害物质清单,其中苯并(a)芘的总得分最高,其次是镉和砷;2-氯萘和邻苯二甲酸二乙酯的总得分最低。最后,通过K均值聚类算法将99种土壤优先管理有毒有害物质划分为5个不同的优先等级,其中苯并(a)芘、镉、砷、汞、铅、镍、苯、六价铬和茚并(1,2,3-cd)芘等9种物质被划定为第一优先等级。最终,结合排放标准制定现状和分析测试方法具备情况,建议可将除茚并(1,2,3-cd)芘以外的第一优先等级物质纳入我国首批重点控制的土壤有毒有害物质名录。

Screening toxic and hazardous substances that need priority management in development land soils is the basis of contamination investigation,risk assessment,quality standard development of soils,and is also the basis of soil pollution management for supervision entities.In this study,the chemical sorting combined with a statistical method was performed on a multi-source dataset that integrating both domestic and foreign data in order to screen soil toxic and hazardous substances that need priority management.In the dataset,we selected 886 toxic and hazardous substances in candidate,and via the integrated analysis method,extracted a list of 123 substances from them that need particular attention for priority management.The parameterized scoring and quantitative evaluation of the 123 toxic and hazardous substances in concern were then carried out using an improved chemical ranking system in terms of human toxicity,exposure potential,environmental management concern,and data certainty.By combining the results of the data certainty score,we established a sequential list of 99 toxic and hazardous substances for priority management.Among which,B(a)P has the highest total score followed by cadmium and arsenic,while 2-chlorine naphthalene and diethyl phthalate had the lowest.Finally,the 99 substances were classified into five priority levels by K-means clustering algorithm.B(a)P,Cd,As,Hg,Pb,Ni,benzene,Cr(Ⅵ),and indeno(1,2,3-cd)pyrene were classified in the first-level priority.Considering the current status of emission standards and soil analytical methods in China,we propose the first-level substances,with the exception of indeno(1,2,3-cd)pyrene,to be included in the first catalog of toxic and hazardous substances under priority control for soil.