LAUSR

Sediments function as a secondary and significant source of tributyltin (TBT) and triphenyltin (TPT) in aquatic ecosystems and may pose a potential threat on benthic organisms and human health. The subchronic toxicity of sediment-associated TBT or TPT to snails Bellamya aeruginosa at environmentally relevant concentrations was investigated in this study. Multiple endpoints at the biochemical [ethoxyresorufin-O-deethylase (EROD), superoxide dismutase (SOD), catalase (CAT), protein carbonyl content (PCC) and lipid peroxidation (LPO)] and transcriptomic levels were examined. TBT or TPT in sediment could induce antioxidant enzymes’ activities and result in oxidative damage in the hepatopancreas of B. aeruginosa after 28-day exposure. A transcriptomic profile of B. aeruginosa exposed to TBT and TPT was reported. CYP genes and EROD activity were sensible and reliable biomarkers for toxicity assessment of TBT or TPT in sediments. Comparative pathway analysis revealed the alteration of steroid hormone biosynthesis and retinol metabolism in B. aeruginosa after 90-day exposure to sediment-associated TBT at the concentration of 2000 ng/g dw, which might affect both reproduction and lipogenesis functions. The ubiquitin proteasome system and immune system might be the toxicity target in B. aeruginosa after exposure to sediment-associated TPT for 90 days. The results offered new mechanisms underlying the toxicity of sediment-associated tributyltin and triphenyltin.