CMNS 137 Technical Communication for Water Engineering Technology

Canadians are exposed to a variety of chemicals, both naturally-occurring and human-made, throughout their daily lives. We understand that many of these chemicals are in our bodies, and there are questions about the potential for these chemicals to affect our health. Public health officials and government regulators need better and more direct measurements of the exposure of Canadians to these chemicals in order to improve decisions for protecting health and preventing disease.

Guidelines for Canadian Drinking Water Quality for PFOS and PFOA

EPA has established health advisories for PFOA and PFOS based on the agency’s assessment of the latest peer-reviewed science to provide drinking water system operators, and state, tribal and local officials who have the primary responsibility for overseeing these systems, with information on the health risks of these chemicals, so they can take the appropriate actions to protect their residents.

Per- and polyfluoroalkyl substances (PFAS) are a group of water-soluble chemical compounds with an important number of applications, which have been widely used during the last 60 years. Two of them, perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), are the most known and well investigated. As for many other organic substances that are of environmental concern, the diet is the main route of human exposure to PFAS. However, in certain cases drinking water may also mean a significant contribution to human exposure, and to a lesser extent, dust and air (indoor exposure). In recent years, the environmental persistence of PFAS, their biomagnification in food webs, as well as their potential accumulation and toxicity, have generated a notable interest, which has been evidenced by the considerable number of publications in this regard. Recently, we carried out a wide revision on the levels of PFAS in food and human dietary intake. In the current review, we have summarized the recent information (last 10 years) published in the scientific literature (Scopus and PubMed) on the concentrations of PFAS in drinking water and the human health risks derived from the regular water consumption, when available. A large amount of data belongs to PFOS and PFOA and corresponds to studies mainly conducted in countries of the European Union, USA and China, although no information is available for most countries over the world. According to the toxicological information about PFAS that is so far available, the current health risks for the regular consumers of municipal/tap water do not seem to be of concern according to the levels considered as acceptable for various regulatory institutions.