Eternal Pollutants in Water: US Proposes Toughest Standard in America
PFAS are very persistent in the environment.
Five weeks after Health Canada, it is the turn of the US Environmental Protection Agency (EPA) to suggest a tolerable contamination threshold for certain so-called “eternal” and potentially carcinogenic contaminants in drinking water. If it becomes official, the recommendation would be the second strictest in the world, after that of Denmark.
It had been awaited for several months by many scientists and environmental groups. Communities across the country have suffered for far too long from the pervasive threat of PFAS [per- and polyfluoroalkyl substances] pollution, said Michael S. Reagan, Administrator of the United States Environmental Protection Agency. .
The EPA has targeted the two most well-known and individually documented contaminants: perfluorooctane sulfonates (PFOS) and perfluorooctanoic acid (PFOA). These substances are used in particular to make water-repellent or grease-resistant coatings and for the manufacture of chemical products, respectively, according to Health Canada. Like other PFAS, they degrade extremely slowly in the environment, hence the name eternal contaminants.
En because of their high chemical stability, perfluoroalkyls and polyfluoroalkyls are used in a multitude of everyday products.
Their concentration should not exceed 4 parts per trillion (ppt) in drinking water, or the equivalent of 4 nanograms per liter (ng/l). This is the typical quantification limit in private laboratories, explains engineer Benoit Barbeau, professor and co-holder of the industrial chair in drinking water. The total quantity of four other types of PFAS could also be regulated.
The EPA predicts that, if fully implemented, this rule will, over time, prevent thousands of deaths and reduce tens of thousands of serious PFAS-related illnesses. This action establishes national protection against PFAS pollution for all persons, the agency's statement read.
The U.S. regulations are subject to consultation and will become final at the end of the year. It will require cities that exceed these future thresholds to intervene to correct the situation.
To meet the proposed standard, more than 5,000 water supply systems will need to find new water sources or install and operate more advanced treatment systems, the American Water Works Association said in a statement.
The current proposal is higher than the health advisory issued in June 2022 by the EPA. This opinion had caused a stir as the thresholds were so low. It was then suggested 0.004 ppt for PFOA and 0.02 ppt for PFOS.
Traces of PFAS in water: what you need to know about these eternal contaminants
ISSUE ICI PREMIÈRE • Tout un matinTraces of PFAS in water: what you need to know about these eternal contaminants. 9-minute audio content, ICI Première show. Listen to audio.
For its part, Health Canada proposes to set at 30 ng/L the objective for the sum of the concentrations of total PFAS detected in drinking water. There is no standard in Quebec on the presence of PFAS in water.
In February, the largest study on the presence of PFAS in drinking water in Quebec was published in the scientific journal Water Research.
Drinking water in almost all Quebec cities contains traces of PFAS. According to scientists, Saint-Donat, in Lanaudière, and Val-d'Or, in Abitibi, show worrying concentrations. Two other municipalities exceed Health Canada's proposal: Sainte-Adèle, in the Laurentians, and Sainte-Cécile-de-Milton, in Estrie.
All those that exceed the Canadian criterion would also be targeted in the United States, observes Sébastien Sauvé, professor of environmental chemistry at the University of Montreal. He is the author of the Quebec study. But there are three new cities in Quebec that exceed one of the EPA criteria: Sainte-Pétronille, Waterloo and Longueuil.
At the time of publication of the study, the national director of public health, Dr. Luc Boileau, assured that the water is very drinkable in Quebec, despite the contaminants. He indicated that Quebec does not have the same industrial history as the United States and that the portrait of PFAS is therefore different. We have a very advantageous situation compared to what we see in the United States and we compare very well to the rest of Canada and to Europe as well.
To some respects, the American proposal is more restrictive than that of Health Canada, explains the professor of environmental chemistry, Sébastien Sauvé. But it would not have detected a case like St-Donat, which is caused by fire-fighting foam products, not included in the United States' calculation.
Benoit Barbeau is the same opinion. There are more Quebec cities that do not meet American recommendations than Canadian ones.
This is the strictest recommendation in America and the second strictest in the world. The Danes are even tougher, he observes, at 2 ppt for four types of PFAS. Health Canada's public consultations are taking place until April 12.