Prediction of Polycyclic Aromatic Hydrocarbon Bioaccessibility to Earthworms in Spiked Soils by Composite Extraction with Hydroxypropyl-β-Cyclodextrin and Organic Acids

• Published in: Pedosphere Vol. 27; no. 3; pp. 502 - 510
• Main Authors: Zhang, Yanan, Yang, Xinglun, Gu, Chenggang, Bian, Yongrong, Liu, Zongtang, Jia, Mingyun, Wang, Fang, Wang, Daizhang, Jiang, Xin
• Format: Journal Article
• Language: English
• Published: Beijing Elsevier Science Ltd 01-06-2017; Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 China; University of Chinese Academy of Sciences, Beijing 100049 China%Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 China%College of Resources and Environment, Henan Agricultural University, Zhengzhou 450002 China
• Subjects: Anthracene; Aromatic hydrocarbons; Benzo(a)pyrene; Bioavailability; Biota; Chrysene; Citric acid; Cyclodextrins; Eisenia fetida; Environmental policy; Fluoranthene; Hydrocarbons; Malic acid; Organic acids; Organic chemistry; Oxalic acid; Phenanthrene; Polycyclic aromatic hydrocarbons; Pyrene; Sediment pollution; Soil contamination; Soils; Worms; β-Cyclodextrin; 低分子量有机酸; 复合; 多环芳烃; 污染土壤; 生物有效性; 羟丙基-β-环糊精; 蚯蚓; 预测; citric acid; low-molecular-weight organic acid; chemical extraction; earthworm accumulation; malic acid
• ISSN: 1002-0160; 2210-5107
• DOI: 10.1016/S1002-0160(17)60346-1

Traditional exhaustive extraction methods often overestimate the risk of polycyclic aromatic hydrocarbon （PAH） bioaccessibility to biota. Therefore, reliable assessment methods need to be established. In this study, a composite extraction with hydroxypropyl- β-cyclodextrin （HPCD） and three low-molecular-weight organic acids, oxalic acid （OA）, malic acid （MA）, and citric acid （CA）, was used to predict the PAH bioaccessibility to earthworms, subjecting to two soils （red soil and yellow soil） spiked with selected PAHs, phenanthrene, pyrene, chrysene, benzo（a）anthracene, benzo（b）fluoranthene, benzo（k）fluoranthene, and benzo（a）pyrene. For both soils, concentrations of PAHs by composite extraction using HPCD-OA （R2 = 0.89-0.92, slope ： 1.89-2.03; n = 35）, HPCD-MA （R2 = 0.92-0.96, slope = 1.43-1.67; n = 35）, and HPCD-CA （R2 = 0.92-0.96, slope = 1.26-1.56; n = 35） were significantly correlated with PAH accumulation in the Eisenia fetida earthworms. Moreover, the HPCD-CA- and HPCD-MA-extracted PAH concentrations were closer to the earthworm-accumulated PAH concentration than the extraction using just HPCD. The results indicated that the composite extraction could improve the prediction of PAH bioaccessibility, and therefore can serve as a reliable chemical method to predict PAH bioaccessibility to earthworms in contaminated soils.