Toxic metals detected near Stablex plant in Blainville, Que.

Marie-Claude Archambault of the Blainville Citizens’ Coalition, Sonja Behmel of WaterShed Monitoring, Sébastien Sauvé, a professor at the University of Montreal, and Martine Ouellet, head of Climat Québec, at a press conference in Montreal on Friday, June 12, 2026. (Stéphane Blais/The Canadian Press)

Water and sediment samples collected near the Stablex plant in Blainville, Que., are contaminated with several toxic metals, according to the results of a sampling campaign initiated by Climat Québec and the Blainville Citizens’ Coalition.

The political party led by Martine Ouellette and the citizens’ coalition invited the media to Montreal on Friday morning to present the results of the sampling campaign conducted in the fall of 2025 near the Stablex industrial waste treatment facility in Blainville.

“We can conclude that there are definitely problems with lead, cadmium, zinc, copper, arsenic, and chromium,” said Sonja Behmel, a limnologist with WaterShed Monitoring, the firm that planned and supervised the sampling.

The results concern Sébastien Sauvé, a professor of environmental chemistry at the University of Montreal, who was present at the press conference.

“What worries me most is that we see there is a lot of cadmium and a lot of lead in the water. In addition, the sediments are also contaminated with arsenic, and there are very high levels of chromium, so all of this together makes me worry about biodiversity in these waterways and about the people living nearby who could also be exposed,” said the holder of the Canada Research Chair in Citizen Science of Emerging Contaminants.

“These metals accumulate in the food chain and persist in the environment for decades,” added Professor Sauvé.

According to the analysis, cadmium concentrations exceed the ACEL (Acute Criterion for the Protection of Aquatic Life) threshold.

Lead levels in the water are said to exceed the AEL-C (Acute Ecotoxicity Level) standard by 113.7 times.

As for sediments, five contaminants—cadmium, arsenic, zinc, copper, and lead—are all reported to exceed “the first alert threshold, the CER,” according to WaterShed Monitoring.

Call for application of precautionary principle

Climat Québec and the Blainville Citizens’ Coalition are calling for an “exhaustive and independent sampling campaign” that would cover “a greater number of sampling points and a higher frequency, conducted by an independent third party.”

They are also calling for the application of the precautionary principle.

“Until this comprehensive campaign has been carried out and the source or sources of contamination have been identified and controlled, any expansion of the site’s operations must be suspended,” they wrote in a press release.

The Stablex industrial waste treatment center currently comprises a treatment plant and five landfill cells, and the company has begun developing a sixth cell.

This American company is expanding its hazardous waste landfill on land that formerly belonged to the City of Blainville and now belongs to the Government of Quebec, despite opposition from the City and frequent protests by citizen groups.

As of Friday morning, Stablex had not yet responded to the results of the sampling campaign.

This report by The Canadian Press was first published in French on June 12, 2026