浙江台州典型电子废弃物无序拆解区土壤多环芳烃污染风险评估

Risk Assessment of Soil Polycyclic Aromatic Hydrocarbons Pollution at A Typical Informal E-waste Dismantling Site in Taizhou, Zhejiang

电子废弃物的无序拆解会导致其中多环芳烃(polycyclic aromatic hydrocarbons, PAHs)的无规律释放,进而对周边生态环境和人体健康构成威胁。为了量化电子废弃物无序拆解区土壤中PAHs的含量及其对人体健康的风险,本研究从浙江省台州市路桥区某典型电子废弃物无序拆解区采集了3个作坊式电子废弃物拆解点、3个作坊式塑料或金属加工点和1个电子废弃物拆解尾渣倾倒点的土壤样品,以气相色谱-质谱联用法和美国环保署规定的暴露量化及风险表征方法为分析手段开展PAHs含量分析及其风险评估。结果发现:上述7个土壤样品PAHs的总量范围为32.62～1053.71μg/kg,平均为414.05μg/kg,其中一个作坊式电子废弃物拆解点的PAHs含量属于重污染级别,土壤存在强烈的环境风险,单体菲(Phe)、蒽(Ant)、荧蒽(Fla)和芘(Pyr)对环境风险的贡献率最大。此外,PAHs通过不同途径对人体造成的健康风险程度为呼吸途径﹥皮肤接触﹥经口途径。结果表明,电子废弃物无序拆解区土壤PAHs污染急需建立相关环境管理措施及污染控制标准,逐步规范电子废弃物无序拆解活动。

Informal dismantling of e-waste results in the irregular emission of polycyclic aromatic hydrocarbons(PAHs),which would pose a great threat to the environment and human health.In order to analyze the concentrations and human health risks of PAHs caused by informal dismantling of e-waste,a typical dismantling area located at Luqiao,Taizhou,was selected as the experimental site.Soil samples were collected from seven sites,including the workshop e-waste dismantling site,the workshop plastic or metal processing site and the e-waste tailings dump site.Also,several methods including gas chromatography-mass spectrometer,exposure quantization and risk assessment were adopted in this research.Results indicated that the total concentrations of PAHs in soils within informal dismantling of e-waste were ranged from 32.62 to 1053.71μg/kg,with the average value of 414.05μg/kg.Especially,the pollution of PAHs at one of workshop e-waste informal dismantling sites was identified as the serious level,and the contribution rate of environmental risk caused by Phe,Ant,Flu and Pyr was the highest.Furthermore,the risk level of PAHs through different pathways to human was determined as follows:breathe pathway﹥skin exposure﹥mouth pathway.It is urgent to establish relevant environmental management measures and pollution control standards,and to standardize the informal dismantling activities of e-waste gradually.