Human exposure to wastewater dis-charged into the environment has increasedwithin the past 15 to 20 years with the risein
populationand the greater demand forwater resources for recreation and otherpurposes. The organisms of concern indomestic wastewater
include enteric bacteria, viruses, and protozoan cysts.
Disinfection is considered to be the primary mechanism for the inactivation/destruction of pathogenic organisms to prevent the spread
of waterborne diseases to downstream users and the environment. It is important that wastewater be adequately treated prior to
disinfection in order for any disinfectant to be effective. There is no perfect disinfectant.