Tsujino Hirofumi, Ikuno Yudai, Haga Yuya, Asahara Haruyasu, Higashisaka Kazuma, Tsutsumi Yasuo
Graduate School of Pharmaceutical Sciences, Osaka University.
The Museum of Osaka University.
Yakugaku Zasshi. 2024;144(2):171-175. doi: 10.1248/yakushi.23-00152-2.
Microplastics are small pieces of plastic that are less than 5 mm in length. These plastics have been detected in various environments, including the ocean, soil, and air. Their abundance have raised concerns regarding their potential effects on living organisms, including humans. The surface of microplastics degrades due to external factors such as ultraviolet rays and water waves in the environment. Therefore, assessing the biological impact of microplastics and considering their state of degradation is important. Among the physical properties of microplastics, we focused on the chemical degradation of microplastics. Specifically, we used vacuum ultraviolet (VUV) light to accelerate the degradation of polyethylene (PE) and prepared PE samples representing the degradation of PE to varying degrees. The surface properties of PE samples prepared using VUV were similar to those obtained from the environment. Cytotoxicity tests were then used to evaluate the effects of undegraded and degraded PE on cells. We found that the severity of cytotoxicity increased with the extent to which the PE would have been degraded, suggesting that the degree of degradation is strongly linked to the severity of the observed deleterious effects on living organisms. In conclusion, this finding contributes to our understanding of the effects of polyethylene microplastics on the human body.
微塑料是长度小于5毫米的小塑料碎片。这些塑料已在包括海洋、土壤和空气在内的各种环境中被检测到。它们的大量存在引发了人们对其对包括人类在内的生物体潜在影响的担忧。微塑料的表面会因环境中的紫外线和水波等外部因素而降解。因此，评估微塑料的生物影响并考虑其降解状态很重要。在微塑料的物理性质中，我们重点关注微塑料的化学降解。具体而言，我们使用真空紫外线（VUV）光来加速聚乙烯（PE）的降解，并制备了代表不同程度PE降解的PE样品。使用VUV制备的PE样品的表面性质与从环境中获得的相似。然后使用细胞毒性测试来评估未降解和降解的PE对细胞的影响。我们发现细胞毒性的严重程度随着PE降解程度的增加而增加，这表明降解程度与观察到的对生物体的有害影响的严重程度密切相关。总之，这一发现有助于我们了解聚乙烯微塑料对人体的影响。
