Biomarker responses of earthworms (Eisenia fetida) to soils contaminated with perfluorooctanoic acid

Perfluorooctanoic acid (PFOA) is considered a persistent environmental pollutant. The aim of this study was to assess the potential toxicity of PFOA to earthworms ( Eisenia fetida ) in artificial soil. The activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and glutathione S -transferase (GST) as well as the contents of malondialdehyde (MDA) were measured after exposure to 0, 5, 10, 20, and 40 mg kg −1 PFOA in soils for 7, 14, 21, and 28 days. The results showed that SOD activity increased at 14 days and decreased from 21 to 28 days; MDA levels were highest in the treatment with 40 mg kg −1 PFOA after 28 days of exposure. In contrast, CAT and POD activities increased after 14–21 days of exposure and significantly decreased with long-term exposure (28 days). GST activity increased significantly from 14 to 28 days. Our results indicate that PFOA has biochemical effects on E. fetida , thereby contributing to our understanding of the ecological toxicity of PFOA on soil invertebrates.