Health Canada announced August 18, 2014, the Guidelines for Canadian Drinking Water Quality-Guideline Technical Document-Ammonia (dated June 2013) has been posed online. It is not considered necessary to establish a health-based guideline for ammonia, based on its low toxicity at concentrations found in drinking water. Levels of ammonia, either naturally present in the source water or added as part of a disinfection strategy, can affect water quality in the distribution system (e.g., nitrification) and should be monitored.
The guideline technical document reviews and assesses all identified health risks associated with ammonia in drinking water. Based on this review, and taking into consideration the lack of an appropriate endpoint from the ingestion of ammonia, the lack of sufficient evidence of systemic effects in humans and limited relevant studies in experimental animals, it has been found that no health-based guideline can be derived for ammonia in drinking water.
Canadian Water and Wastewater Association