Potassium permanganate, a purplish chemical whose use as a disinfectant was originally developed in the 1800’s, is a strong nonchlorine oxidant with a long history of safe use in drinking water, wastewater, and chemical manufacturing industries. It has been used by water treatment plants as an oxidizer since the turn of the century, and is commonly used in municipal facilities for water purification. It is widely used for oxidation of iron and manganese and to correct taste and odor problems in treated water because of its ability to produce oxidation reactions with inorganic compounds and organic substances (Claudi and Mackie 1994).
Potassium permanganate produces effective control of adult zebra mussel at 2.0 mg L-1, and inhibits veliger settlement at 1.0 mg L-1 and below (San Giacomo and Wymer 1997). It does not produce trihalomethanes or haloacetic acids (San Giacomo and Wymer 1997). Although it costs more than chlorine, it can be less expensive than proprietary molluscicide chemicals. It requires a long contact time. It may not be 100 percent effective (Fraleigh et al. 1993). Overdosing may result in an unacceptable pink coloration in water. Agencies using this control method include the City of Baltimore, Public Works (Balog et al. 1995) and the City of Buffalo, NY (San Giacomo and Wymer 1997).