污水灌溉土壤中As暴露的健康风险研究

Health Risk Analysis of Arsenic Exposure in Soils Using Sewage for Irrigation

在分析污水灌溉地区灌溉污水、大气、地下水监测数据以及As污染区流行病学调查资料的基础上,以污灌导致的膳食As暴露为研究对象,探讨了灌溉污水As浓度与人群As中毒患病率之间的关系,并以石家庄污灌区为例,研究了污灌区As的可接受风险灌溉浓度。结果表明,当健康风险度R<2×10-3时,风险为可接受的。污灌区As的可接受风险灌溉浓度为<0.033mg·L-1。建立了污水灌溉的安全年限(s)与土壤中As的可接受风险灌溉浓度(Ca)的关系图,为污灌的科学管理以及污灌区As污染的控制提供了参考。

Based on analysis of monitoring data of an arsenic pollution area irrigated with sewage and information about chronic arsenicism of arsenic conta mination, integrating the transference process of arsenic from sewage to bodies with relationship between rate of chronic arsenicism and estimation of accumulat ive intake level, a quantitative study of health risk assessment on arsenic expo sure to residents at an area using sewage for irrigation in Shijiazhuang City wa s studied. It was suggested that safe limited time of irrigation by sewage and t he acceptable maximum of arsenic concentration in sewage be estimated. The resul t showed that among the residents born in 2002 there were 16.33%diagnosed wit h chronic arsenic absorption if arsenic concentration in sewage remained consist ent and the acceptable maximum of arsenic concentration was 0.033 mg·L-1. Th e prandial arsenic exposure was the most important part of the total arsenic exp osure (about 80%at the study on residents born in 2002). The acceptable maxim um of arsenic concentration would change when the safe limited time of irrigatio n by sewage changed and the range of the change would diminish when the safe lim ited time of irrigation by sewage aggrandized. Using this method in the article, the environmental objective for the utilization of the sewage may be quantified more accurately.