Harmful algal events in the mediterranean sea: new toxins and monitoring studies

In the late ‘80s we afforded the first experimental evidence over the occurrence of okadaic acid in the Adriatic Sea. Since then, our study has been a cornerstone in analyzing algal toxic outbreaks along the Italian coastline. Over the last decade, we have detected yessotoxins as the most occurring Adriatic toxins, while okadaic acid - predominant in the early ‘90s - has slowly subsided until disappearing around the turn of the new millennium. Because of the strong difference in harmfulness between okadaic acid (a potent tumor promoter) and yessotoxins (with no significant oral toxicity), the EU set up a new protocol for separating these toxins in two distinct layers. However, in samples of toxic Adriatic mussels we have recently individuated two new desulfocarboxyhomoyessotoxins that get co-extracted in the same layer as okadaic acid; thus a revision of the protocol is now in order. Lately, we characterized a number of spirolides - some of them never reported before - after the detection of massive occurrence of Alexandrium ostenfeldii in the Adriatic plankton. The latest threat to public health is placed by some Ostreopsis spp., known to produce palytoxin. These dinoflagellates have been infesting the Mediterranean Sea since 2005, when some 200 bathers suffered from respiratory disorders after exposition to marine aerosols in Genoa, Italy. We set up a new LC/MS method for detecting palytoxin, and by employing it on some toxic samples from Genoa, we demonstrated for the first time the presence of a putative palytoxin in the Italian seawaters.