University of Bologna, Department of Biological, Geological, and Environmental Sciences, Via Sant'Alberto 163, 48123, Ravenna, Italy.
SINTEF Ocean, Environment and New Resources, Trondheim, Norway.
Environ Pollut. 2021 Aug 15;283:117081. doi: 10.1016/j.envpol.2021.117081. Epub 2021 Apr 4.
Ocean contamination by synthetic polymers can represent a risk for the fitness of marine species due to the leaching of chemical additives. This study evaluated the sub-lethal effects of plastic and rubber leachates on the mussel Mytilus galloprovincialis through a battery of biomarkers encompassing lysosomal endpoints, oxidative stress/detoxification parameters, and specific responses to metals/neurotoxicants. Mussels were exposed for 7 days to leachates from car tire rubber (CTR), polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS) and polyvinyl chloride (PVC), containing organic additives and metals in the ng-μg/L range. The leachate exposure affected general stress parameters, including the neutral lipid content (all leachates), the lysosomal membrane stability (PS, PP, PVC and CTR leachates) and lysosomal volume (PP, PVC and TR leachates). An increased content of the lipid peroxidation products malondialdehyde and lipofuscin was observed in mussels exposed to PET, PS and PP leachates, and PP, PVC and CTR leachates, respectively. PET and PP leachates increased the activity of the phase-II metabolism enzyme glutathione S-transferase, while a decreased acetylcholinesterase activity was induced by PVC leachates. Data were integrated in the mussel expert system (MES), which categorizes the organisms' health status based on biomarker responses. The MES assigned healthy status to mussels exposed to PET leachates, low stress to PS leachates, and moderate stress to PP, CTR and PVC leachates. This study shows that additives leached from selected plastic/rubber polymers cause sub-lethal effects in mussels and that the magnitude of these effects may be higher for CTR, PVC and PP due to a higher content and release of metals and organic compounds.
海洋中的合成聚合物污染可能会对海洋物种的适应性造成风险，这是由于化学添加剂的浸出。本研究通过一系列生物标志物评估了塑料和橡胶浸出物对贻贝 Mytilus galloprovincialis 的亚致死效应，这些生物标志物包括溶酶体终点、氧化应激/解毒参数以及对金属/神经毒物的特异性反应。贻贝在含有 ng-μg/L 范围内有机添加剂和金属的汽车轮胎橡胶（CTR）、聚丙烯（PP）、聚对苯二甲酸乙二醇酯（PET）、聚苯乙烯（PS）和聚氯乙烯（PVC）浸出物中暴露 7 天。浸出物暴露影响了一般应激参数，包括中性脂质含量（所有浸出物）、溶酶体膜稳定性（PS、PP、PVC 和 CTR 浸出物）和溶酶体体积（PP、PVC 和 TR 浸出物）。暴露于 PET、PS 和 PP 浸出物的贻贝中观察到脂质过氧化产物丙二醛和脂褐素含量增加，而暴露于 PP、PVC 和 CTR 浸出物的贻贝中则分别观察到脂质过氧化产物丙二醛和脂褐素含量增加。PET 和 PP 浸出物增加了相 II 代谢酶谷胱甘肽 S-转移酶的活性，而 PVC 浸出物则降低了乙酰胆碱酯酶的活性。数据被整合到贻贝专家系统（MES）中，该系统根据生物标志物反应对生物体的健康状况进行分类。MES 将健康状态分配给暴露于 PET 浸出物的贻贝，将低应激状态分配给 PS 浸出物，将中应激状态分配给 PP、CTR 和 PVC 浸出物。本研究表明，从选定的塑料/橡胶聚合物中浸出的添加剂会对贻贝造成亚致死效应，并且由于 CTR、PVC 和 PP 中含有更高含量和释放的金属和有机化合物，这些效应的程度可能更高。
