Study on the Mechanism and Potential of Corbicula fluminea (Asian Clam) in Removing Copper and Cadmium from Aquaculture Ponds

Abstract

The issue of heavy metal pollution in aquaculture ponds is becoming increasingly severe, posing a significant threat to the healthy development of the aquaculture industry. Heavy metals such as cadmium and copper accumulate in ponds, not only exerting toxic effects on aquatic organisms and affecting their growth and reproduction but also endangering human health through the food chain. Bioremediation, as a green and environmentally friendly technology, utilizes specific organisms to absorb, transform, and immobilize heavy metals. We examined metal accumulation, traditional metal-related biomarkers, alongside transcriptomic and tissue histological analyses, in the hepatopancreas of Corbicula fluminea following a 14-day exposure to copper (20 µg/L), cadmium (20 µg/L), or combined copper-cadmium treatments (20 µg/L Cu and 20 µg/L Cd). Metal exposure led to notable metal accumulation in the clam’s hepatopancreas. Analysis of traditional biomarkers revealed signs of cellular injury and oxidative stress in clams post-metal exposure. Transcriptomic analysis across the three treatment groups revealed disruptions in immune response, response to metal ion, and energy metabolism, characterized by differential expression levels of key genes such as ABCA3, MYD88, TOLLIP, TBK1, C2, C4, c-Myc, SYK, and SAMHD1. These findings deepen our understanding of the adverse effects of metal exposure on freshwater organisms and evaluate the potential of Corbicula fluminea for removing heavy metals from aquaculture ponds.