The toxicology of microcystins and its implication on human health.


  • Department of Environmental Sciences, Dr. R.M.LAvadh University, Faizabad, U.P, 224001, India


Eutrophication is a widely recognized problem of water quality deterioration. Discharge of urban, industrial and agricultural waste has increased the quantum of various chemicals that enter the receiving waters, and alters the physicochemical characteristic. The exploiding human population demanding more and more food, thereby pressing for more use of chemical fertilizers, and the residue of these chemicals reaches into fresh water reservoirs. The increasing nutrients results into prevalence of algal blooms in fresh waters, placing greater pressure on uses of water for both drinking and recreational purposes. Cyanobacterial blooms consisting Microcystis aeroginosa found in several parts of the world causes lethal poisoning to human, livestocks, wildlife and aquatic animals. Microcystin enters in the food chain through zooplankton, fish and aquatic animals. Microcystins toxins are naturally produced poisons stored in the cells of cyanobacterium M. aeroginosa. Human are affected with water related exposure of microcystins with range of symptoms including stomach cramps, vomiting, nausea, diarrhoea, fever, headache, muscle pain, flirtter of the mouth and liver damage. In addition, microcystins causes protein phosphatase inhibition and the cells suffers from oxidative stress. Thus, cyanotoxin phytotoxicity and zootoxicity strongly suggests a need for the surveillance ofcyanoharmful algal bloom and the monitoring of water quality for drinking as well as for other purposes.


Allelopathy, Cyanobacterial blooms, Microcystin, Toxicity, Drinking water.

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