Effects Of Organotin Compounds Pollution On The Physiological And Biochemical Characteristics Of Crassostrea Gigas

Since 1960s, organotin compounds, such as tributyltin(TBT) and triphenyltin (TPT) were widely used as effective components in antifouling paints to prevent fouling creature from adhereing to ship and ocean construct. Although this kind of paints has brought about great profit to the shipping, it brought severe environmental problem. In this paper, we took oyster which was easily suffered from organotin compounds pollution as material and studied the effects of organotin compounds on oyster from point of view of biochemistry, cell and molecular biology. The results showed as follows:The activities of Alkaline Phosphatase(ALP) and Superoxide Dismustase (SOD) of the oysters cultured at varied TBT levels for 96h showed different changes. The activity of ALP decreased at low TBT concentrations but increased at high concentrations and that of SOD markedly declined with increasing TBT concentrations.ALP and SOD isolated and purified from the oyster which were collected from unpolluted sea area were treated by TBT. Their activities, heat-proof, acid-proof and alkaline-proof of the two enzymes were inhibited with increasing TBT concentrations.The effect of TBT on the phagocytic activity of oyster haemocytes was studied in vitro and in vivo. TBT pollution could apparently inhibit the phagocytic activity of haemocytes, and the effect increased with increasing TBT concentrations. It was found that haemocytes were more sensitive to TBT in vitro than that in vivo.The cell activity exposed to different TBT concentrations for 5 days reduced as TBT concentrations increased. But the cells death rate compared with control had insignificant difference at low doses (0.02-2 P g/L).There were 72 differential DNA fragments in the cells disposed to different levels of TBT compared with control by the random amplified polymorphic DNA(RAPD). The number of differential DNA fragments had no relativity with the TBT concentrations. Some of the same fragments were different in fluorescence strength.The results of single cell gelelectrophoresis(SCGE) showed that there was a significant dose-effect between TBT concentrations and DNA damage of gill cells.DNA-damaged gill cells were assayed in six concentrations of TBT compared with the control and the percentage of DNA-damaged gill cells increased with increasing TBT concentrations. It was suggested that TBT might have genetic toxicity to oyster.The results in the present study suggested TBT pollution had effects on Crassostrea gigas in the aspects of biochemistry -, cell and molecular biology.