典型废物回收园区土壤中邻苯二甲酸酯分布与风险评价

Distribution and risk assessment of phthalic acid ester(PAEs)in soil from a multi-waste recycling area

采集天津典型废物回收园区(分为室外回收区和规范化厂区两部分)和周边农田土壤样品36个,分析了土壤中美国环保部优先监测的邻苯二甲酸酯(phthalic acid ester,PAEs)的含量,并进一步研究了污染物的分布特征、环境来源和生态风险.结果表明,7种PAEs在不同土壤中均有不同程度检出.规范化厂区和农田土壤中∑PAEs含量分别为0.889—2.22、0.385—2.54 mg·kg^(-1),显著低于室外回收区∑PAEs含量(1.81—15.9 mg·kg^(-1)).邻苯二甲酸二异(2-乙基)己脂(DEHP)是最主要的PAEs污染物,平均贡献率70%.主成分分析结果表明,研究区域土壤中PAEs主要来源于废料回收、再利用过程中的排放.风险评价结果表明,部分土壤DEHP暴露对成人和儿童的致癌风险超出了可接受水平.废物回收园区,特别是室外操作模式带来的PAEs的暴露风险应引起重视.

Phthalic acid esters（ PAEs）,listed as priority pollutants by United States Environmental Protection Agency,were analyzed in the soil samples obtained from a multi-waste recycling area where different operation modes（ recycling at outdoor or in workshop） coexisted. The contamination features,sources and ecotoxicological risks of PAEs in the soil were investigateed. Seven PAEs were detected and ΣPAEs concentrations decreased in the following order： outdoor recycling sites（ 1.81—15.9 mg·kg^（-1）） workshop（ 0.889—2.22 mg·kg^（-1）） nearby farmlands（ 0.385—2.54 mg·kg^（-1））.Di-（ 2-ethylhexyl） phthalate（ DEHP） was the most dominating congener in the soil samples,accounting for 70% of the total PAEs. Principle component analysis（ PCA） revealed that the PAEs in the soil were mainly derived from the emission during the process of waste recovery and reuse. The risk assessment results showed that the carcinogenic risk of DEHP for adults and children at some sites exceeded acceptable levels. Therefore,more studies should be conducted on PAEs contamination in waste recycling area,especially for where primary outdoor recycling operation exists.