RESPONSES OF ATLANTIC SALMON AND BIVALVE MOLLUSCS TO PARALYTIC SHELLFISH

Paralytic shellfish poisoning (PSP) toxins are a group of potent neurotoxins produced by certain strains of marine dinoflagellates. Blooms of these algal species can result in the passage of PSPs through marine food webs, with detrimental effects on the marine environment and human health. These toxins have been implicated as the causative agent in some of the many fish kills that have occurred during blooms of PSP producing dinoflagellates. As such, PSPs represent a potential threat to fisheries resources and aquaculture. Little is known of the fate of these compounds in fish, but they have been shown to accumulate in the liver of mackerel sampled after bloom events. Analysis of fish tissues also suggests that transformation of these toxins does occur following absorption since the PSP analogues differ from those to which the fish were exposed. The induction of xenobiotic metabolising enzyme activities has also been noted in Atlantic salmon exposed to PSPs and may represent a detoxification mechanism. Better understood is the fate of PSPs in shellfish. Bivalve molluscs accumulat