Killing of pathogenic organisms in water treatment is called...

Disinfection refers to the process of killing or inactivating pathogenic organisms in water, making it safe for human consumption. This is a critical step in water treatment, particularly to eliminate pathogens that could cause waterborne diseases. Methods of disinfection commonly include the use of chlorine, ultraviolet light, or ozone, all of which target harmful microorganisms effectively.

While the other processes mentioned have their own significance, they serve different purposes. Oxidation refers to the chemical reaction where substances lose electrons, which can help in removing organic material and certain contaminants in water, but it does not specifically target pathogens. Pasteurization is a heat treatment process often used in food and beverage industries to kill pathogens but is not typically used for large-scale water treatment. Sterilization aims to kill all forms of microbial life, not just pathogens, and is more extensive than what is needed for drinking water treatment. Thus, disinfection is specifically designed to make water potable by reducing or eliminating harmful organisms, making it the appropriate choice in this context.