Effect of Heavy Metal Ions on Steroid Estrogen Removal and Transport in SAT Using DLLME as a Detection Method of Steroid Estrogen

• Main Authors: Ge Zhang, Yuesuo Yang, Ying Lu, Yu Chen, Wenbo Li, Siyuan Wang
• Format: Article
• Language: English
• Published: MDPI AG 2020-02-01
• Series: Water
• Subjects: natural steroid estrogens; soil aquifer treatment; dispersive liquid–liquid micro-extraction; heavy metal ions; groundwater; high-performance liquid chromatograph
• Online Access: https://www.mdpi.com/2073-4441/12/2/589

Environmental endocrine-disrupting chemicals have become a global environmental problem, and the distribution, transport, and fate of estrogens in soil and water environments closely relate to human and ecological health as well as to the remediation scheme design. A new micro-extraction technique termed dispersive liquid−liquid micro-extraction (DLLME) combined with high-performance liquid chromatography with fluorescence detector (HPLC-FLD) was developed for the determination of the concentration of steroid estrogens in water samples. The detection limits of HPLC-FLD and DLLME-HPLC/FLD were 0.68−1.73 μg L^−1 and 7.16−69.22 ng L^−1, respectively. Based on this method, the isothermal adsorption of 17β-E2 on sand and a breakthrough experiment of 17β-E2 and Cu²⁺ in a soil aquifer treatment (SAT) system were studied. The 17β-E2 adsorption capacity of sand in 17β-E2 solution was detected to be larger than that in a mixed solution of 17β-E2 and Cu(NO₃)₂ solution, and the breakthrough curves of 17β-E2 and Cu²⁺ in the mixed solution shifted forward in sand column experiments. Both suggested that the competitive adsorption of 17β-E2 and Cu²⁺ in the mixed solution might occur on the surface of the sand. In the process of the removal of 17β-E2 in wastewater by SAT, the existence of Cu²⁺ slightly inhibited the adsorption of 17β-E2 and accelerated the breakthrough of 17β-E2. These results ought to be a warning for SAT application for 17β-E2 removal in water where heavy metals coexist.