Di-(2-Ethylhexyl) Phthalate as a Chemical Indicator for Phthalic Acid Esters: An Investigation into Phthalic Acid Esters in Cultivated Fields and E-Waste Dismantling Sites

Abstract Phthalic acid esters (PAEs) represent an ongoing pollution problem and have attracted extensive attention due to their ubiquitous presence in the environment. We investigated the distribution of 6 PAEs (benzyl butyl phthalate [BBP], dibutyl phthalate [DBP], di-(2-ethylhexyl) phthalate [DEHP], diethyl phthalate [DEP], dimethyl phthalate [DMP], and di-n-octyl phthalate [DnOP]) in cultivated soils, including vegetable fields and paddy fields, as well as the soils of E-waste dismantling sites. We also explored the relationship between the particle size of soils and the distribution of PAEs, put forward a novel method to forecast the occurrence and fate of PAEs in soils with DEHP used as a chemical indicator, and made a preliminary assessment of the potential ecological risks of the 6 target compounds in soils. The results showed that the detection rate of target PAEs was 100%, and that the concentrations of ∑6PAEs ranged from 1.2 to 7.3 mg/kg in vegetable fields, 1.2 to 1.5 mg/kg in paddy fields, and 11.8 to 17.9 mg/kg in E-waste dismantling sites. In addition, DEHP exhibited the maximum concentrations (0.480–15.34 mg/kg) in all soil samples. The results also showed that in the wake of decreasing particle size, increasing soil organic carbon would enhance the sorption of PAEs in soils. Moreover, the correlation formula of DEHP successfully predicted the concentrations of other PAEs and ∑ 6PAEs in soils, suggesting that DEHP could be a dependable chemical indicator for forecasting the environmental occurrence of PAEs in soils. Based on the residual levels in the trial sites and limited toxicity data, high risks to soil organisms are expected for DBP, DEP, and DEHP, and low–medium risks for BBP, DnOP, and DMP. Environ Toxicol Chem 2019;00:1–11. © 2019 SETAC