Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China.
Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China.
Environ Pollut. 2020 Feb;257:113475. doi: 10.1016/j.envpol.2019.113475. Epub 2019 Oct 31.
It is of environmental significance to study the leaching performance of additives from microplastics (MPs) and further evaluate the toxicity of leachate to microalgae. Here, we investigated the effects of accelerated aging on characteristics, leaching, and toxicity of commercial lead chromate pigmented MPs. Results show that aging of MPs caused surface cracks and fragmentation, increased their surface area and carbonyl contents, and promoted the release of lead chromate pigment. Chromium (Cr) and lead (Pb) tend to leach under acidic condition, rather than neutral and alkali environment. Aging treatment facilitates the leaching performance and a high concentration of NaCl solution also favors the leaching process. Toxicology experiments demonstrate that only high concentration of leachate (>10 μg L) exerted significant inhibitory influence (p < 0.005) on cell photosynthesis of Microcystis aeruginosa. The growth inhibition of algal cells remarkably increased with increasing leachate concentrations. We observed more inhibiting effects on cell growth and photosynthesis using the leachates of aged MPs. Longer aging time leads to more release of Cr and Pb, rendering higher toxicity to microalgae. These novel findings will benefit us from assessing the leaching behavior of additives in MPs and their toxicological risks to aquatic organisms.
研究添加剂从微塑料（MPs）中的浸出性能，并进一步评估浸出液对微藻的毒性，具有环境意义。在这里，我们研究了加速老化对商用铬酸铅着色 MPs 的特性、浸出和毒性的影响。结果表明，MPs 的老化导致表面出现裂缝和碎片，增加了它们的表面积和羰基含量，并促进了铬酸铅颜料的释放。铬（Cr）和铅（Pb）倾向于在酸性条件下浸出，而不是中性和碱性环境。老化处理促进了浸出性能，高浓度的氯化钠溶液也有利于浸出过程。毒理学实验表明，只有高浓度的浸出液（>10μg/L）对铜绿微囊藻的细胞光合作用才表现出显著的抑制作用（p<0.005）。藻细胞的生长抑制随着浸出液浓度的增加而显著增加。我们观察到老化 MPs 的浸出液对细胞生长和光合作用的抑制作用更强。较长的老化时间导致更多的 Cr 和 Pb 释放，对微藻的毒性更高。这些新发现将有助于我们评估 MPs 中添加剂的浸出行为及其对水生生物的毒理学风险。
