Biological Research Laboratory, Post-Graduation Program in Conservation of Cerrado Natural Resources, Goiano Federal Institute - Urutaí Campus, Urutaí, GO, Brazil.
São Leopoldo Mandic Research Center and Institute, Araras, SP, Brazil.
J Hazard Mater. 2020 Jan 15;382:121066. doi: 10.1016/j.jhazmat.2019.121066. Epub 2019 Aug 24.
Microplastics (MPs) are critical emerging pollutants found in the environment worldwide; however, its toxicity in aquatic in amphibians, is poorly known. Thus, the aim of the present study is to assess the toxicological potential of polyethylene microplastics (PE MPs) in Physalaemus cuvieri tadpoles. According to the results, tadpoles' exposure to MP PE at concentration 60 mg/L for 7 days led to mutagenic effects, which were evidenced by the increased number of abnormalities observed in nuclear erythrocytes. The small size of erythrocytes and their nuclei area, perimeter, width, length, and radius, as well as the lower nucleus/cytoplasm ratio observed in tadpoles exposed to PE MPs confirmed its cytotoxicity. External morphological changes observed in the animal models included reduced ratio between total length and mouth-cloaca distance, caudal length, ocular area, mouth area, among others. PE MPs increased the number of melanophores in the skin and pigmentation rate in the assessed areas. Finally, PE MPs were found in gills, gastrointestinal tract, liver, muscle tissues of the tail and in the blood, a fact that confirmed MP accumulation by tadpoles. Therefore, the present study pioneering evidenced how MPs can affect the health of amphibians.
微塑料（MPs）是全球环境中存在的一种重要的新兴污染物，但它们在水生两栖动物中的毒性知之甚少。因此，本研究旨在评估聚乙烯微塑料（PE MPs）对 Physalaemus cuvieri 蝌蚪的毒理学潜力。根据结果，暴露于浓度为 60mg/L 的 MP-PE 中 7 天的蝌蚪表现出致突变作用，这可以通过观察到核红细胞数量增加来证明。暴露于 PE MPs 的蝌蚪的红细胞和核的面积、周长、宽度、长度和半径较小，以及核/细胞质的比例降低，证实了其细胞毒性。在动物模型中观察到的外部形态变化包括总长度与口-肛距离、尾长、眼部面积、口部面积等比例的降低。PE MPs 增加了皮肤中的黑色素细胞数量和评估区域的色素沉着率。最后，在鳃、胃肠道、肝脏、尾部肌肉组织和血液中都发现了 PE MPs，这一事实证实了蝌蚪对 MPs 的积累。因此，本研究开创性地证明了 MPs 如何影响两栖动物的健康。
