文献类型：期刊文献

英文题名：Effect of polyethylene, polyamide, and polylactic acid microplastics on Cr accumulation and toxicity to cucumber (Cucumis sativus L.) in hydroponics

作者：Zhang, Qi[1];Gong, Kailin[1];Shao, Xuechun[1];Liang, Weiyu[1];Zhang, Wei[1,2];Peng, Cheng[1,2]

机构：[1]East China Univ Sci & Technol, Sch Resource & Environm Engn, State Environm Protect Key Lab Environm Risk Asses, Shanghai 200237, Peoples R China;[2]Shanghai Inst Pollut Control & Ecol Secur, Shanghai 200092, Peoples R China

年份：2023

卷号：450

外文期刊名：JOURNAL OF HAZARDOUS MATERIALS

收录：;EI(收录号：20231013666281);WOS:【SCI-EXPANDED(收录号:WOS:000948948800001)】；

基金：This study was supported by the National Natural Science Founda- tion of China (42177395, 41807461, and 41877124) .

语种：英文

外文关键词：Microplastics; Cr(VI); Cucumber; Accumulation; Phytotoxicity; Antioxidant system

摘要：Microplastics (MPs) in farmland soil may affect the environmental fate and toxicity of heavy metals; however, how non-biodegradable and biodegradable MPs change the accumulation and phytotoxicity of Cr(VI) to the plants is still unknown. In this study, we explored the impacts of Cr(VI) concentrations (0, 20, 50, 100, 200, and 500 mu mol/L), MP types (polyethylene (PE), polyamide (PA), and polylactic acid (PLA)), sizes (13, 48, and 500 mu m), and concentrations (40, 200, and 1000 mg/L) on the Cr accumulation and toxicity to cucumber (Cucumis sativus L.) under hydroponic conditions for 14 days. The results show that the presence of PE-MPs promoted the Cr accumulation in root by 8-39.8%. However, PA-MPs inhibited the Cr accumulation in the whole plant under less than 100 mu mol/L Cr(VI). Notably, 1000 mg/L PA-MPs significantly reduced Cr accumulation in root and stem by 44.70% and 48.20%, respectively. Moreover, PE-MPs and PLA-MPs reduced the chlorophyll content and slowed down the growth of seedlings, while PA-MPs were beneficial to the growth of cucumber under 50-500 mu mol/L Cr(VI) treatments, increasing the biomass by 20.99-189.99%. Furthermore, PE-MPs enhanced the con-tent of MDA, especially under 500 mu mol/L Cr(VI) concentration by 27.39%; however, the addition of PA-MPs and PLA-MPs slightly enhanced the enzyme activities including superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT). Significantly, 1000 mg/L PA-MPs promoted biomass and reduced MDA content compared the control due to their high Cr(VI) adsorption efficiency. Thus, MP type, especially PE-MPs, mainly determined the Cr accumulation and phytotoxicity, which was attributed to the various adsorption capacities of MPs to Cr(VI).