Measuring endocrine disruptors in wastewater
“There is interest in Quebec and around the world in finding ways to track endocrine disruptors. These methods could even identify where the contamination is coming from in a given area — whether it’s from agricultural, hospital, municipal, or industrial environments,” says Professor Valérie Langlois.
The pair of researchers is also working with municipal and industrial partners to monitor drinking water and wastewater to plan for potential infrastructure changes. Unlike many current techniques that test on fish, their method does not involve animal testing. Instead, their approach uses human cell lines, genetically modified in the laboratory to be sensitive to certain hormones.
“When an endocrine disruptor activates the receptors on these cells, they emit a small light. That’s how we determine whether the wastewater could be posing a risk to the hormonal system,” explains Julie Robitaille, a doctoral student in water sciences. However, she says that further research is needed to reveal how their cellular findings translate to aquatic species.
The contaminant cocktail
The challenge in monitoring wastewater comes from the “cocktail” of endocrine disruptors it contains. “You can’t just look at whether each individual substance is present. You need to analyze whether the entire mixture has any effect, since these contaminants can have different consequences when combined with other chemicals,” says the PhD student.
To test the effects of the pollutant mix, the researchers turned to bioassays, using the biological analyses to measure the reactions of their cell lines when exposed to wastewater samples, without knowing exactly which contaminants they contained.
Robitaille used several techniques to demonstrate the effectiveness of this type of approach, one of which involved making an inventory of all the tools available to regulatory authorities. She conducted this literature review in collaboration with scientists who are members of the Intersectoral Centre for Endocrine Disruptor Analysis (ICEDA). The publication appeared in the Environmental Research journal’s 2022 Special Issue on Endocrine Disrupting Chemicals.