The hydroxyl radical generation and oxidative stress for the earthworm Eisenia fetida exposed to tetrabromobisphenol A

Biochemical effects of tetrabromobisphenol A (TBBPA) on the earthworm Eisenia fetida, including superoxide dismutase, catalase, glutathione-S-transferase, reduced glutathione, oxidized glutathione, GSH/GSSG ratio and malondialdehyde (MDA) level, were measured to assess ecological toxicity of TBBPA. With OECD standard filter-paper contact test method, earthworms were exposed to TBBPA of a range of concentrations (0.00, 0.01, 0.05, 0.1, 0.5 and 1.0 mg L⁻¹). According to the electron paramagnetic resonance spectrum, reactive oxygen species (ROS) generated in the earthworm was identified as the hydroxyl radical (^•OH) which was significantly induced at all TBBPA concentrations. With the increasing of TBBPA concentration, the antioxidant enzymes, glutathione and MDA levels varied significantly. The results showed that TBBPA exerts its toxic effects on E. fetida by inducing the generation of ROS and resulting in oxidative damage. The results show that the ^•OH production leads to oxidative stress in the tissues of the earthworm E. fetida.