Long term changes of associated metal contamination of marine sediments affected by coastal mining of asbestos
2025
Galgani, Francois | Bouchoucha, Marc | Brach-papa, Christophe | Andral, Bruno | Connes, Coralie | Gonzalez, Jean-louis | Tomasino, Corinne | Paoli, Catherine | Baldi, Yoann | Chiffoleau, Jean-francois
In this study, we examined the impact of asbestos mining residues on the marine environment at the Canari site in Corsica. Over 20 years, sediment (20 sites), water (10 sites), and biota (394 samples) were analyzed for trace metals, using various methods including AAS and ICP-MS, and toxicity. Laser granulometry and radionuclide dating enabled to assess sediment characteristics and accumulation rates. The results reveal substantial metal contamination in sediments near the mine, with peak concentrations reaching 4.743 mg/kg of chromium, 1.646 mg/kg of nickel, and 140 mg/kg of cobalt, higher than levels observed in reference areas. Leaching of metals, with elevated nickel concentrations (up to 2.95 μg/L) near the mine was observed during rainy weather, decreasing further away. Biota analyses, including caged mussels and sea urchins, also demonstrated bioaccumulation of heavy metals, with maximum concentrations of chromium in sea urchins reaching 13.1 mg/kg in 2012 and 12.506 mg/kg in 2020. Up to 100 % larval anomalies were observed at several stations after toxicity tests. The study also showed significant metal contamination in fish (1.15 mg/kg dw in liver) and lobsters (up to 57.7 μg/kg dw in liver). Despite some reductions in contamination levels, the persistence of toxic metals and their clear southward movement pose ongoing environmental and public health concerns. The findings highlight the need for continuous monitoring and risk assessment, as well as precautionary measures for local fishermen and call for further research to assess potential health risks for consumers, who may be locally exposed through seafood consumption.
显示更多 [+] 显示较少 [-]