College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, China.
Shenyang Urban Construction University, Shenyang 110167, China.
J Hazard Mater. 2024 Dec 5;480:136056. doi: 10.1016/j.jhazmat.2024.136056. Epub 2024 Oct 10.
Polyethylene microplastics (PE-MPs) are commonly found alongside fungicides in farmland soils. However, the toxic effects of varying PE-MP sizes and concentrations on soil fauna in fungicide-contaminated soils are unclear. This study aimed to investigate the impact of different PE-MP sizes (13, 48, and 150 µm) and concentrations (0.05 % and 0.25 %) on tebuconazole accumulation, oxidative stress, and gut bacteria in earthworms. The results indicated that earthworms exposed to MP13-H accumulated the highest tebuconazole on day 7, 19.77 % higher than tebuconazole alone, 7.27 % higher than MP48-H, and 10.30 % higher than MP150-H. MP13-H led to the most severe oxidative stress, significantly increasing the oxidative biomarkers catalase and peroxidase in earthworms. After 28 days, the expression of glutathione sulfotransferase genes was the lowest in the MP13-H group, while the antibacterial defense gene heat shock protein 70 and translationally controlled tumor protein were the highest, indicating severe DNA damage and increased toxicity to earthworms. Further, 150-µm PE-MPs caused the most severe damage to the intestinal epithelium. Moreover, PE-MPs induced an increase in the abundance of specific gut bacterial community associated with oxidative stress. The study suggested that PE-MPs changed the migration of fungicides to earthworms, induced oxidative stress, altered gene expression, and modified the gut microbiota, thereby increasing the risk to earthworms.
聚乙烯微塑料（PE-MPs）通常与杀菌剂一起存在于农田土壤中。然而，不同尺寸和浓度的 PE-MP 对杀菌剂污染土壤中土壤动物的毒性影响尚不清楚。本研究旨在研究不同尺寸（13、48 和 150 µm）和浓度（0.05%和 0.25%）的 PE-MP 对噻菌灵积累、氧化应激和蚯蚓肠道细菌的影响。结果表明，暴露于 MP13-H 的蚯蚓在第 7 天和第 19.77%的噻菌灵单独处理中积累了最高的噻菌灵，比 MP48-H 高 7.27%，比 MP150-H 高 10.30%。MP13-H 导致最严重的氧化应激，显著增加蚯蚓中的氧化生物标志物过氧化氢酶和过氧化物酶。28 天后，MP13-H 组谷胱甘肽硫转移酶基因的表达最低，而抗菌防御基因热休克蛋白 70 和翻译控制肿瘤蛋白的表达最高，表明 DNA 严重受损，对蚯蚓的毒性增加。此外，150 µm 的 PE-MPs 对肠上皮造成最严重的损伤。此外，PE-MPs 诱导与氧化应激相关的特定肠道细菌群落丰度增加。该研究表明，PE-MPs 改变了杀菌剂向蚯蚓的迁移，诱导了氧化应激，改变了基因表达，并改变了肠道微生物群，从而增加了蚯蚓的风险。
