Studies on dynamics of microcystin pollution level in municipal water supplies

Microcystin is a kind of hepatotoxic peptide produced by cyanobacterium which has been found worldwide in eutrophicated potable water source. It has caused poisoning of animal and also posed a health hazard to human. The method of HPLC was applied to examine exactly the contents of trace intracellular and extracellular LR, YR, RR microcystin in source water and treated water, of which the samples were collected from August 1998 to June 1999 and concentrated by ODS silica gel column. The results showed that microcystins-LR was detected at 0.07~0.78(g/L in source water and not found in treated water. The microsystin-RR was detccted at the level of 0.08~2.71(g/L in source water and 0.07~1.09(g/L in treated water, while the microcystin-YR was detected at zero level. The total microcystin was higher in October and June than that in other months; therefore, there exists microcystin pollution in the municipal water supplies with obviously seasonal variation of the level of microcystin. The results are conducive to choosing water source reasonably as well as to regulating hygienic criterion of microcystin in drinking water.