Effects on human health of some toxic cyanobacteria (blue‐green algae) in reservoirs, lakes, and rivers

The public water supply has been implicated in gastrointestinal disorders in the United States, East Africa, and Australia, associated with the lysis of heavy blooms of cyanobacteria. The causative organisms include Microcystis, Anabaena, Aphanizomenon, and Oscillatoria. Using epidemiological techniques, we have shown significant increase in liver enzymes in blood, particularly γ-glutamyl transpeptidase, during a toxic bloom in the reservoir of a city. Therefore, public health awareness of the risks, and consequent action to control water blooms and remove harmful compounds from drinking water supplies, is required.