Water Treatment, Municipal

Abstract

Understanding the pathway of pathogens in the environment is very important for the protection of human health. One of the sources of pathogens is wastewater that is discharged without or with treatment or recycled for many purposes. Among many pathogens, Cryptosporidium parvum , Giardia lamblia , and humanvirulent microsporidia (i.e., Enterocytozoon bieneusi , Encephalitozoon intestinalis , Encephalitozoon hellem , and Encephalitozoon cuniculi ) are human anthropozoonotic enteropathogens that inflict considerable morbidity on healthy people. In addition, many viruses exist within wastewater, especially enteric viruses, which originate from the human gastrointestinal tract. Over 120 enteric viruses have been identified to be pathogenic to humans at low infectious doses. Therefore, treatment technologies for wastewater have been continuously improving due to the more strict limits set, including microbial control, and also due to reuse practices because of the increasing water scarcity problem in a number of regions of the world. As secondary treatment, many biological processes have been applied. However, these are able to remove pathogens only to some extent. Thus, tertiary treatment, including constructed wetlands (CWs), sand filtration, stabilization ponds, and membrane filtration, has been used for microbial removal. Still, many resistant pathogens need to be removed and for this purpose the use of advanced oxidation as tertiary or disinfection processes is required so as to ensure the safe discharge and reuse potential of the effluent.