期刊
ENVIRONMENTAL RESEARCH
卷 205, 期 -, 页码 -出版社
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.envres.2021.112433
关键词
PFAS; Montmorillonite; Adsorption; Bioavailability
资金
- NIEHS SRP (Superfund Hazardous Substance Research and Training Program) [P42 ES027704]
- USDA Hatch [6215]
The study found that nutrient-amended clays can effectively reduce the bioavailability of PFAS in soil and decrease the risk of PFAS translocation to plants.
Consumption of food and water contaminated with per- and polyfluoroalkyl substances (PFAS) presents a significant risk for human exposure. There is limited data on high affinity sorbents that can be used to reduce the bioavailability of PFAS from soil and translocation to plants and garden produce. To address this need, montmorillonite clay was amended with the nutrients carnitine and choline to increase the hydrophobicity of the sorbent and the interlayer spacing. In this study, the binding of PFOA (perfluorooctanoic acid) and PFOS (perfluomoctanesulfonic acid) to parent and amended clays was characterized. Isothermal analyses were conducted at pH 7 and ambient temperature to simulate environmentally-relevant conditions. The data for all tested sorbents fit the Langmuir model indicating saturable binding sites with high capacities and affinities under neutral conditions. Amended montmorillonite clays had increased capacities for PFOA and PFOS (0.51-0.71 mol kg(-1)) compared to the parent clay (0.37-0.49 mol kg(-1)). Molecular dynamics (MD) simulations suggested that hydrophobic and electrostatic interactions at the terminal fluorinated carbon chains of PFAS compounds were major modes of surface interaction. The safety and efficacy of the clays were confirmed in a living organism (Lemna minor), where clays (at 0.1% inclusion) allowed for increased growth compared to PFOA and PFOS controls (p <= 0.01). Importantly, soil studies showed that 2% sorbent inclusion could significantly reduce PFAS bioavailability from soil (up to 74%). Studies in plants demonstrated that inclusion of 2% sorbent significantly reduced PFAS residues in cucumber plants (p <= 0.05). These results suggest that nutrient-amended clays could be included in soil to decrease PFAS bioavailability and translocation of PFAS to plants.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据