Abstract
Improper processing activities of e-waste are potential sources of polycyclic aromatic hydrocarbons (PAHs) and their derivatives, however, information about the environmental occurrence and adverse impacts of these toxic substances is still limited for informal e-waste recycling areas in Vietnam and Southeast Asia. In this study, unsubstituted and methylated PAHs were determined in surface soil and river sediment samples collected from a rural village with informal e-waste recycling activities in northern Vietnam. Total levels of PAHs and MePAHs decreased in the order: workshop soil (median 2,900; range 870–42,000 ng g−1) > open burning soil (2,400; 840–4,200 ng g−1) > paddy field soil (1,200; range 530–6,700 ng g−1) > river sediment samples (750; 370–2,500 ng g−1). About 60% of the soil samples examined in this study were heavily contaminated with PAHs. Fingerprint profiles of PAHs and MePAHs in the soil and sediment samples indicated that these pollutants were mainly released from pyrogenic sources rather than petrogenic sources. The emissions of PAHs and MePAHs in this area were probably attributed to uncontrolled burning of e-waste and agricultural by-products, domestic coal and biomass combustion, and traffic activities. Carcinogenicity and mutagenicity of PAHs in the e-waste workshop soils were significantly higher than those of the field soils; however, the incremental lifetime cancer risk of PAH-contaminated soils in this study ranged from 5.5 × 10−9 to 4.6 × 10−6, implying acceptable levels of human health risk. Meanwhile, concentrations of some compounds such as phenanthrene, anthracene, fluoranthene, benz[a]anthracene, and benzo[a]pyrene in several soil samples exceeded the maximum permissible concentrations, indicating the risk of ecotoxicological effects.
Recommended citation
Nguyen Thi Quynh Hoa, Hoang Quoc Anh, Nguyen Minh Tue, Nguyen Thanh Trung, Le Nhu Da, Tran Van Quy, Nguyen Thi Anh Huong, Go Suzuki, Shin Takahashi, Shinsuke Tanabe, Pham Chau Thuy, Pham Thi Dau, Pham Hung Viet, Le Huu Tuyen (2020). Soil and sediment contamination by unsubstituted and methylated polycyclic aromatic hydrocarbons in an informal e-waste recycling area, northern Vietnam: Occurrence, source apportionment, and risk assessment, Science of The Total Environment, Volume 709, 135852, https://doi.org/10.1016/j.scitotenv.2019.135852. (SCIE, p-ISSN 0048-9697, IF = 6.551).
