Ministry of Ecology and Environment of China, Nanjing Institute of Environmental Sciences, Nanjing, China.
Jiangsu Academy of Agricultural Sciences, Nanjing, China.
Environ Sci Pollut Res Int. 2023 Apr;30(19):57041-57049. doi: 10.1007/s11356-023-26213-z. Epub 2023 Mar 17.
In real-field soil conditions, multiple chemicals exposure may be the real scenario for soil biota. The co-occurrence of microplastics (MPs) and cadmium (Cd) is common in soils, which may pose a potential risk to soil ecosystems. Degradable microplastics are producing more MPs, and the potential effects on soil ecosystems are unknown. Therefore, a standard soil animal collembolan Folsomia candida was used to evaluate the single and interaction effects of biodegradable MPs (PLA) and Cd. The results showed that single and co-biodegradable PLA and Cd all had negative influences on the survival, reproduction, and growth of F. candida, and the effects intensified with PLA concentrations. The survival rate, reproduction rate, adult body length, and juvenile body length decreased by 20.0%, 24.2%, 22.9%, and 32.2% at MPs-100 treatment. But combined PLA and Cd alleviated the toxicity of single Cd on F. candida at lower PLA concentrations. The number of juveniles increased by 29.3%, the survival rate increased by 7.52%, the adult body length increased by 11.7%, and the juvenile body length increased by 19.0% at MPs-1 + Cd than single Cd treatment. Biochemical assays on antioxidant enzymes had the same results. Antioxidant enzymes CAT and POD were more sensitive than SOD. CAT and POD activities were induced quickly at shorter exposure periods, and MP treatment thus may be promising biomarkers on soil collembolan for soil MP exposure. PLA is degraded with time in soils; therefore, the long-term effects of co-MPs and Cd in soils are suggested to be further studied.
在真实的田间土壤条件下，多种化学物质的暴露可能是土壤生物区系的真实情况。微塑料（MPs）和镉（Cd）在土壤中共同出现的情况很常见，这可能对土壤生态系统构成潜在风险。可生物降解的微塑料正在产生更多的 MPs，其对土壤生态系统的潜在影响尚不清楚。因此，使用标准的土壤动物弹尾目昆虫 Folsomia candida 来评估可生物降解 MPs（PLA）和 Cd 的单一和相互作用效应。结果表明，单一和共可生物降解的 PLA 和 Cd 都对 F. candida 的生存、繁殖和生长产生负面影响，并且随着 PLA 浓度的增加，这种影响加剧。在 MPs-100 处理下，存活率、繁殖率、成虫体长和幼体体长分别下降了 20.0%、24.2%、22.9%和 32.2%。但在较低的 PLA 浓度下，PLA 和 Cd 的组合减轻了单一 Cd 对 F. candida 的毒性。幼体数量增加了 29.3%，存活率提高了 7.52%，成虫体长增加了 11.7%，幼体体长增加了 19.0%，比单一 Cd 处理时更高。抗氧化酶的生化测定也得到了相同的结果。CAT 和 POD 比 SOD 更敏感。CAT 和 POD 活性在较短的暴露期内迅速被诱导，因此 MPs 处理可能是土壤弹尾目昆虫对土壤 MPs 暴露的有前途的生物标志物。PLA 会随着时间在土壤中降解；因此，建议进一步研究土壤中共同 MPs 和 Cd 的长期影响。
