In 2017, the Government of Canada, released “Enteric Viruses in Drinking Water,” a document bringing awareness to the risk of viruses in drinking water, with the intent of updating the current drinking water guidelines.
The enteric viruses of most concern as human health hazards in Canadian drinking water sources include noroviruses, rotaviruses, hepatitis viruses, enteroviruses and adenoviruses.
Amongst a select few solutions discussed, Ultraviolet light-emitting diodes (UV-LEDs), at the time considered an emerging technology for UV water treatment, (Wright et al., 2012), was highlighted.
“Five disinfectants are commonly used in drinking water treatment: free chlorine, monochloramine, ozone, chlorine dioxide and UV light. All are chemical oxidants except UV light which uses electro-magnetic radiation. Chemical disinfectants inactivate microorganisms by destroying or damaging cellular structures, metabolism, biosynthesis and growth whereas UV light damages pathogens’ nucleic acid which prevents their replication such that they are unable to complete cycles of infection.”
The article outlines the subject of a multi-barrier approach to water treatment as effective, with UV and free chlorine as a practical example in response to risk assessments, “Many Canadian source waters will require a greater log removal and/or inactivation to maintain an acceptable level of risk.”