研究报告
闫晓露,郑欢,赵烜杭,于瑶光,钟敬秋.辽东湾北部河口区土壤重金属污染源识别及健康风险评价[J].环境科学学报,2020,40(8):3028-3039
辽东湾北部河口区土壤重金属污染源识别及健康风险评价
- Source identification and health risk assessment of soil heavy metal in the estuary of Northern Liaodong Bay, China
- 基金项目:国家自然科学基金项目(No.41976206,41671158);辽宁省教育厅人文社科研究项目(No.WQ2019020);辽宁省社会科学规划基金项目(No.L19CJY005);辽宁省大学生创新创业训练项目(No.201910165190);辽宁师范大学校级科研项目(No.BS2018L007, CX201902012)
- 闫晓露
- 1. 辽宁师范大学海洋经济与可持续发展研究中心, 大连 116029;2. 中国科学院沈阳应用生态研究所, 沈阳 110016
- 郑欢
- 辽宁师范大学地理科学学院, 大连 116029
- 赵烜杭
- 辽宁师范大学地理科学学院, 大连 116029
- 于瑶光
- 辽宁师范大学地理科学学院, 大连 116029
- 钟敬秋
- 1. 辽宁师范大学海洋经济与可持续发展研究中心, 大连 116029;2. 中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室, 北京 100101
- 摘要:选取我国北方典型河口区—辽东湾北部区为研究对象,共采集129个表层土样,测定了Cu、Cr、Cd、Ni、Zn和Pb等土壤重金属含量,利用地统计分析、地累积指数(Igeo)、内梅罗指数、潜在生态风险指数(RI)、多元统计分析及健康风险模型对研究区土壤重金属的空间分布特征、污染来源及健康风险进行系统分析,并对区域人居环境改善提出对策建议.结果表明:①研究区土壤中Cu、Cr、Cd、Ni、Zn和Pb的平均含量分别为17.87、148.97、1.31、40.91、102.86和12.42 mg·kg-1,除Cu和Pb以外都超过了辽宁省土壤背景值;②6种重金属污染程度排序为Cd > Cr > Zn > Ni > Cu > Pb,其中Cd元素污染最严重;土壤重金属综合生态风险指数RI为325.689,处于重度生态风险水平,Cd是主要的生态风险因子;③多元统计分析表明,重金属Cu、Zn和Pb主要受自然因素影响,Cr和Ni主要源于生活及工业废水排放,Cd以磷肥的大量使用、石油化工生产及工业活动作为主要的人为来源;④健康风险评价结果表明,皮肤接触暴露途径中儿童的非致癌风险大于成人,呼吸暴露途径中成人的致癌风险大于儿童,元素Cr的总致癌风险Rall<10-6,不存在致癌风险,Cd的总致癌风险10-4 < Rall < 10-6,存在可接受致癌风险;⑤河口海岸区对我国海湾及沿海区域经济发展意义重大,土壤重金属污染和人居健康问题已经不容忽视,希冀本研究可为当地政府及同类区域提供科学借鉴.
- Abstract:A total of 129 topsoil samples collected in Northern Liaodong Bay were analyzed for contents of Cu, Cr, Cd, Ni, Zn and Pb, so as to evaluate the spatial distribution characteristics, risk status and pollution sources of heavy metals in the soils by using geostatistical analysis, geo-accumulation index (Igeo), Nemerow index, potential ecological risk index (RI) and health risk model, as well as multivariate statistical analysis methods, such as correlation analysis and principal component analysis. And countermeasures and suggestions were put forward for improving the regional living environment. The results of this study showed that the average contents of heavy metals of Cu, Cr, Cd, Ni, Zn and Pb in the soils in the northern part of Liaodong Bay were 17.87, 148.97, 1.31, 40.91, 102.86 and 12.42 mg·kg-1, respectively, which, except for Cu and Pb, were all exceeding the background values in Liaoning Province. The accumulation index and pollution degree of these 6 heavy metals were ranked as Cd > Cr > Zn > Ni > Cu > Pb, with Cd being the most serious pollutant. The potential ecological risk index (RI) of 325.689 reached a high potential ecological risk level, with Cd being the most affecting element. Multivariate statistics showed that Cu, Zn and Pb were mainly derived from soil parent materials, while Cr and Ni were mainly from coal combustion, waste gas, wastewater discharge and other industrial activities; and Cd mainly came from phosphorous pesticide usage, petrochemical production and industrial wastewater discharge. The health risk assessment indicated that the non-carcinogenic risk for children in skin-contact exposure pathways was higher than that for adults, but the carcinogenic risk for adults in respiratory exposure pathways was higher than that for children. The total carcinogenic risk of element Cr was less than 10-6, meaning no carcinogenic risk; and the total carcinogenic risk of Cd was between 10-4 and 10-6, meaning an acceptable carcinogenic risk. As estuarine areas are of great significance for the economic development of gulf and coastal regions in China, the problems of soil heavy metal pollution for human health shall not be ignored. Therefore, this study can provide important scientific reference for local governments and similar regions.