Metal contamination of intertidal sediment and macroalgae in an area impacted by paint from abandoned boats

Metals commonly employed in boat paint (Ba, Cr, Cu, Pb, Sn and Zn) have been determined in 63-mu m-fractionated intertidal sediments and in Ulva lactuca and Fucus vesiculosus sampled in the vicinity of abandoned vessels. Metal concentrations in sediment were elevated but highly variable, both between sites and amongst replicates from the same site (e.g., mean Cu - 100 to 1200 mg kg-1; mean Pb - 130 to 6900 mg kg-1) due to heterogeneous contamination by metal-rich boat paint particles. Concentrations of all metals except Zn were higher in U. lactuca than F. vesiculosus but in both species metal levels were also elevated and variable. These observations were attributed to contamination by sediment particles and physical and chemical interactions between fine, suspended or deposited paint particles and the algal surface. The latter interactions act as a means by which boat paint metals may enter the foodchain.

Automated summary

Metals commonly used in boat paint, such as Ba, Cr, Cu, Pb, Sn, and Zn, were found in sediment and algae samples collected near abandoned vessels. The concentrations of these metals in sediment were elevated but highly variable due to contamination by metal-rich boat paint particles. The levels of metals in the algae species U. lactuca were generally higher than in F. vesiculosus, and this was attributed to physical and chemical interactions between the algae and the deposited paint particles. These findings suggest a potential pathway for boat paint metals to enter the food chain.