A review of shellfish phycotoxin profile and toxic phytoplankton species along Croatian coast of the Adriatic Sea

Abstract

       Toxin analyses along Croatian coast of the Adriatic Sea started in mid 1990s when okadaic acid has been determined in shellfish from Kaštela Bay (central Adriatic Sea). Since then, the toxin profile of Adriatic shellfish has become complex and the number of recorded toxic and potentially toxic species has increased over the time. Up to date, phycotoxins determined in Adriatic shellfish or phytoplankton belong to various groups od toxins: okadaic acid toxin group, saxitoxin group, domoic acid group, yessotoxins (YTXs), pectenotoxins (PTXs), gymnodimines (GYMs), spirolides (SPX) and palytoxins (PLTs). Toxins from okadaic acid group and YTXs are highlighted as the main phycotoxins in shellfish along Croatia coast of the Adriatic Sea. Toxins from okadaic acid group has been determined in high concentration that could endanger human health while YTXs have been determined more often in shellfish samples, comparing to other phycotoxins. Regarding toxic phytoplankton species reported in the Adriatic Sea, only for ten species toxin production has been confirmed and 20 species are suspected to be toxic. Toxicity has been confirmed for eight dinoflagellates species: Alexandrium minutum, Alexandrium ostenfeldii, Dinophysis fortii, Gonyaulax spinifera, Lingulodinium polyedrum, Ostreopsis cf. ovata, Prorocentrum lima, Protoceratium reticulatum and two diatom species Pseudo-nitzschia delicatissima and Pseudo-nitzschia multiseries. Toxin profile has yet to be defined for other potentially toxic phytoplankton species found along Croatian coast of the Adriatic Sea. Most of those species are Dinophysis and Pseudo-nitzschia species, which are relatively common and abundant in this area as well as toxins from okadaic acid group in shellfish.