The Production, Distribution and Fate of Yessotoxins, Taking the northern Yellow Sea of China for Example

Yessotoxins(YTXs) is a phycotoxin produced by phytoplankton that has been reported as cardiotoxic and have been detected in microalgae and/or bivalve molluscs in many countries. Their presence in shellfish was discovered due to their high acute toxicity in mice after i.p. injection of lipophilic extracts. YTXs in sediment, seawater, plankton and shellfish in the northern Yellow Sea of China were investigated. The least YTXs level and the lowest detection rate occurred in sediment, while a maximum level of 24.6ng/L appeared in the plankton; the change trend in seawater was similar to that in plankton. YTXs in mussel and Chlamys farreri were all higher than it in oyster. The three dinoflagellates which can produce YTXs, Protoceratium reticulatum, Lingulodinium polyedrum and Gonyaulax spinifera, have been all found. The abundance change of toxic dinoflagellates was consistent with YTXs in plankton, seawater and shellfishes. P. reticulatum is one of the main microalgae which can produce YTXs in the northern Yellow Sea coast; this P. reticulatum have been separated from seawater, and its ecological features of production YTXs have been studied. The distribution of YTXs in particulate matters, seawater, and shellfishes has also been studied by the experiments of feeding trial to Patinopecten yessoensis, Chlamys farreri and mussel. The more YTXs would distribute in particles and seawater, while in shellfishes there was the smallest proportion, only 1% around. According to the results in this paper, the ecological functions of the northern Yellow Sea coast as aquiculture area was still good, but the potential ecological risk of YTXs cannot be ignored.