Accumulation power of some bivalve molluscs

Several surveys were performed along the Italian coasts in marine areas in which molluscs grow, to evaluate the hygienic quality of shellfish, shellfish rearing water, and sand beds. The samples were analysed by the MPN technique for faecal coliforms. The results of the analyses confirmed previous studies: different species of molluscs show differential capacity to accumulate micro-organisms and suggest that the microbiological water analysis does not always reflect the microbiological quality of the molluscs.