Health Canada’s Water and Air Quality Bureau, Safe Environments Directorate recently released Guidelines for Canadian Drinking Water Quality Guideline Technical Document – Vinyl Chloride. According to the guidelines, the maximum acceptable concentration (MAC) for vinyl chloride in drinking water is 0.002 mg/L (2 μg/L). "Every effort should be made to maintain vinyl chloride levels in drinking water as low as reasonably achievable (ALARA)".

Vinyl chloride is primarily a synthetic chemical and can enter drinking water through leaching from polyvinyl chloride (PVC) pipes; industrial discharges from chemical and latex manufacturing plants; or as a result of the biodegradation of synthetic solvents.

The guideline technical document reviews and assesses all identified health risks associated with vinyl chloride in drinking water, incorporating all relevant routes of exposure from drinking water — namely, ingestion as well as inhalation and skin absorption from showering and bathing.

Vinyl chloride is classified as a human carcinogen, with sufficient evidence in both humans and animals. Vinyl chloride exposure has been linked with liver and neurological effects, in both humans (at occupational exposure levels) and animals. Liver cancer is the most serious endpoint that follows exposure from ingestion or inhalation of vinyl chloride.