Besides oxidizing iron and manganese, potassium permanganate has been found to be most effective in controlling...

• A. zebra mussels
• B. algae
• C. bacteria
• D. viruses

Answer: (A)

Potassium permanganate is a strong oxidant used in water treatment to remove iron and manganese and to oxidize organic compounds, odors, and colors. It also helps control biofouling on surfaces exposed to treated water. Among the options, zebra mussels are the most effectively controlled because they are directly exposed to the oxidant on the surfaces they attach to, and the oxidizing action can damage their tissues and shells, leading to mortality with appropriate dosing and contact time. In contrast, algae, bacteria, and viruses are generally more resistant to the levels of permanganate used for oxidizing iron and manganese or require different disinfectants and longer contact times to achieve reliable inactivation. So, zebra mussels best fit the use of permanganate beyond its role in iron and manganese oxidation.