Metal salts such as alum and iron sulfate combined with chlorine formulated as a powder can transform muddy contaminated source waters into clear, safe drinkable water. Two private manufactures of such powdered mixtures and tablets include the Procter & Gamble company in the United States and Control Chemicals in South Africa. Several field trials using the Procter & Gamble product have demonstrated significant health reductions from its usage, particularly in outbreak and emergency response situations.