Water safety: Risks of filtration pitchers and heat exposure

Experts have identified several risks regarding water consumption related to filtration devices and heat exposure.

Regarding filtration pitchers, the French Agency for Food, Environmental and Occupational Health & Safety (Anses) warns that saturated activated carbon cartridges can cause ‘reverse pollution.’ Instead of purifying water, a used filter may release previously trapped toxins back into the liquid. Additionally, improper maintenance can lead to the development of bacterial biofilms. Warning signs include a chlorine or earthy taste, a moldy odor, or the visible presence of a slippery film or black spots on the equipment.

In terms of bottled water, nutritionists note that while closed bottles generally remain safe for a few hours, extreme heat in vehicles can pose risks. When car interiors reach 60 to 70 °C, the quality of the water can degrade chemically through the migration of substances from the plastic, or organoleptically through changes in taste and smell. If a bottle has already been opened, heat can accelerate the multiplication of bacteria introduced by the mouth. Consumers should discard water that has an unusual plastic taste, an abnormal odor, or a visibly deformed bottle.