Chronic chlorpyrifos exposure induces oxidative stress, neurological damage, and hepatopancreas enrichment in Chinese mitten crab (Eriocheir sinensis)

Abstract

The toxic effects of long-term exposure to low doses of chlorpyrifos (CPF) on Eriocheir sinensis were evaluated using acute toxicity tests, transcriptome analyses, and metabolome profiling. Four groups (three replicates per group, 60 crabs)—control (no CPF exposure), high exposure (0.12 mg/L CPF), medium exposure (0.036 mg/L), and low exposure (0.012 mg/L)—were subjected to CPF for 21 days. Tissue damage, antioxidant enzyme activity, transcriptional changes, and metabolic alterations in E. sinensis were analyzed. The results demonstrated that CPF disrupted the regulatory networks of transcription and metabolism in crabs under the experimental concentration conditions, with the severity of effects increasing as the duration of exposure lengthened despite the crabs' efforts to activate key defense mechanisms, such as upregulation of cholinesterase 1-like gene expression, to counteract organophosphorus toxicity and adapt to CPF presence in their environment. Even at low concentrations (0.012 mg/L), neurobehavioral development and the antioxidant kinase system in crabs were impaired, leading to hepatopancreatic tissue lesions that negatively affect their growth and survival rates. Additionally, E. sinensis accumulates significant levels of CPF, which may pose food safety concerns when humans consume them. Therefore, ensuring the rational use of CPF requires maintaining appropriate water concentrations to minimize direct harm to aquatic organisms and indirect impacts on food safety associated with this pesticide.