College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China.
College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China; Research Center of Analysis and Measurement, Zhejiang University of Technology, Hangzhou, 310014, China; Environmental Microplastic Pollution Research Center, Zhejiang University of Technology, Hangzhou, 310014, China.
Environ Pollut. 2020 May;260:113988. doi: 10.1016/j.envpol.2020.113988. Epub 2020 Jan 14.
Microplastic pollution is a major global environmental problem in both aquatic and terrestrial environments. Pesticides are frequently applied to agricultural soil to reduce the effects of pests on crops, but may also affect the degradation of plastics. In this study, we generated microplastics from polyethylene (PE) film and biodegradable poly(butylene adipate-co-terephthalate) (PBAT) film and determined (1) the effect of prothioconazole on degradation of the microplastics, and (2) the adsorption and release characteristics of heavy metals (Cr, Cu, As, Pb, Ba, and Sn) by the microplastics during degradation process. Changes of surface functional groups and morphologies were measured by FTIR and SEM, while metal concentrations were determined by ICPMS. Prothioconazole was found to promote plastic degradation. PBAT degraded faster and adsorbed more heavy metals from the soil than PE. Whether the microplastics adsorb or release heavy metals depended on the metal and their concentrations. Prothioconazole inhibited the adsorption of Cr, As, Pb and Ba by microplastics, promoted the adsorption of Cu, and had no significant effect for Sn. These results can help to assess the ecological risk of microplastic pollution from plastic mulch when combined with heavy metals.
微塑料污染是水生和陆地环境中一个主要的全球性环境问题。杀虫剂经常被应用于农业土壤中，以减少害虫对作物的影响，但也可能影响塑料的降解。在这项研究中，我们从聚乙烯（PE）薄膜和可生物降解的聚（丁二酸丁二醇酯-对苯二甲酸酯）（PBAT）薄膜中生成了微塑料，并确定了（1）丙硫菌唑对微塑料降解的影响，以及（2）在降解过程中微塑料对重金属（Cr、Cu、As、Pb、Ba 和 Sn）的吸附和释放特性。通过傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）测量了表面官能团和形貌的变化，而金属浓度则通过电感耦合等离子体质谱（ICPMS）测定。结果发现，丙硫菌唑促进了塑料的降解。PBAT 比 PE 降解更快，从土壤中吸附更多的重金属。微塑料是否吸附或释放重金属取决于金属及其浓度。丙硫菌唑抑制了微塑料对 Cr、As、Pb 和 Ba 的吸附，促进了 Cu 的吸附，对 Sn 没有显著影响。这些结果有助于评估与重金属结合时塑料覆盖物微塑料污染的生态风险。
