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

作　　者：ZHANG Yanan YANG Xinglun GU Chenggang BIAN Yongrong LIU Zongtang JIA Mingyun WANG Fang WANG Daizhang JIANG Xin 

机构地区：[1]Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences [2]University of Chinese Academy of Sciences [3]College of Resources and Environment, Henan Agricultural University

出　　处：《Pedosphere》2017年第3期502-510,共9页土壤圈（英文版）

基　　金：supported by the National Key Basic Research Development Program (973) (No. 2014CB441105);the National Natural Science Foundation of China (Nos. 41271327, 41271464 and 21377138)

摘　　要：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(R^2= 0.89–0.92, slope = 1.89–2.03; n = 35), HPCD-MA(R^2=0.92–0.96, slope = 1.43–1.67; n = 35), and HPCD-CA(R^2= 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.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.

关 键 词：chemical extraction citric acid earthworm accumulation low-molecular-weight organic acid malic acid 

分 类 号：X53[环境科学与工程—环境工程] TQ460.4[化学工程—制药化工]