Abstract
The microcystins in source and tap water collected from seven waterworks around a lake in summer, 1996 were detected by enzyme-linked immunosorbent assay (ELISA). Microcystins were determined in the source water from all the seven waterworks, and the concentrations ranged from 280 to 35,300 ng/L. Low concentrations of microcystins were also detected in the tap water of three waterworks. The results suggest that microcystins in source water could not be removed completely by conventional adding bleaching powder treatment.