Health Effects Associated with Wastewater Treatment, Disposal, and Reuse

Treated and raw waters in two water treatment plants in Malaysia were tested for Giardia cysts and Cryptosporidium oocysts. Cryptosporidium was not detected, and no correlation could be determined between concentrations of Giardia cysts and fecal coliforms in the raw water. Cysts, oocysts, and coliforms were not detected in the treated water. The occurrence of hepatitis A in three workers at a wastewater-treatment plant during a small community outbreak was reported. Because the workers had no risk factor to the disease outside of their occupation, this report confirmed that hepatitis A is an occupational hazard for wastewater workers but is preventable by vaccination. A strain of Poliovirus 3 was identified through molecular analysis of cell cultures that were infected by aerosols generated at a wastewater-treatment plant near Pisa, Italy. The need for adequate occupational protection in treatment plants and caution in the use of treated wastewater for irrigation were discussed.