Toxicity of French strains of the dinoflagellate Prorocentrum minimum experimental and natural contaminations of mussels

Mediterranean strains of Prorocentrum minimum do not appear to have the sam e toxic component as Japanese strains since they showed no cytotoxicity for hepatocytes in culture. However, their toxic components, which appear to b lock calcium channels, were detectable by the immobilisation test on Dipter a larvae. A bio-accumulation experiment in the laboratory showed that the t oxins could accumulate in nearly equivalent amounts in the hepatopancreas a nd meat of cultured mussels. The same toxicity was found in natural samples collected in a period of bloom of P. minimum. These results suggest that P . minimum could be responsible for shellfish toxicity in the natural enviro nment and thus present a risk for human health. (C) 1999 Elsevier Science L td. All rights reserved.