Trace metals in the bivalve molluscs Ruditapes decussatus and Ruditapes philippinarum from the Atlantic Coast of Southern Spain

Total concentrations of Cu, Zn, Mn, Ni, Cr, Cd, Ph, Fe, As, and Hg were determined in two marine bivalves R. decussatus and R. philippinarum from the Southern Spanish Atlantic Coast. The concentrations of Fe, Ni, Cr, Cu, and As in R. decussatus were significantly higher (p < 0.01) than in R. philippinarum; however, R. philippinarum contained more Hg. The levels of Cu, Zn, Ph, Hg, Cd, and Mn were significantly higher (p < 0.01) in the samples taken in the Province of Huelva than in the samples from the Province of Cadiz. According to Spanish legislation, all the samples analysed were suitable for human consumption. Three kinds of relationships between metal concentration and the size of R. decussatus and R. philippinarum were found: positive for As, Hg, Ph, Ni, and Cd; negative for Cu, Zn, and Fe; and no correlation for Mn and Cr. (C) 1997 Elsevier Science Ltd.