Paralytic phycotoxin uptake by scallops (Pecten maximus)

Abstract

We performed experimental contaminations of scallops (Pecten maximus ) from Port-en-Bessin (Normandy, France) using a toxic Japanese strain of Alexandrium tamarense . During the contamination/decontamination experiment on different tissues (digestive gland, muscle, gonad), extracts were obtained using cold acetic acid 0.1 N to maintain the perfect integrity of the toxin profile. These initial trials indicated that with a daily concentration of 2 x 10 super(6) cells/l a maximum toxicity equivalent to 850 mu g/100 g of digestive gland meat was attained in 2 weeks. Concerning toxin profiles, it would appear that gonad can selectively accumulate gonyautoxins, particularly GTX2/GTX3, even though the relative amount of uptake always follows the order hepatopancreas > gonad > muscle. Moreover, studies of Japanese scallops imported in 1990 showed that 80% of the gonad and muscle samples included all or part of the kidneys and excretory organs, whose relationship with gonad toxicity need further clarification.