High metal contents in the fan mussel Pinna nobilis in the Balearic Archipelago (western Mediterranean Sea) and a review of concentrations in marine bivalves (Pinnidae)

Concentrations of metals (Cd, Cu, Hg, Pb and Zn) in the marine bivalve Pinna nobilis at several coastal locations of Majorca and the Cabrera Islands (Mediterranean Sea) were investigated. The elevated concentrations of metals found in the soft tissues of P. nobilis indicate high bioaccumulation factors. All concentrations and the calculated metal pollution index showed significant differences between sites, with particularly high concentrations in the Cabrera Archipelago, a marine protected area (MPA). The datasets were evaluated with the limited information published in the literature for Pinnidae species worldwide. In benthic P. nobilis, concentrations of Cd, Cu and Zn are more than 30 times higher and Hg and Pb concentrations are 4 and 7 times higher, respectively, than concentrations in other bivalve species, such as Mytilus galloprovincialis (Mytilidae). These observations from species inhabiting nearby ecological habitats of the coastal environment (Pinnidae vs. Mytilidae) are also discussed in the context of current marine monitoring strategies and assessments.