A recent study revealed that the bacteria that causes Legionnaire’s disease can grow in windshield washer fluid. Legionnaire’s disease is a pneumonia-like condition that, if left untreated, can be fatal.
The study, conducted in Arizona, tested five different brands of washer fluid, all taken from school buses. Researchers found the legionella bacteria in 75% of the samples.
The findings are alarming because the windshield washer fluid can release the disease-causing bacteria into the air, which could be inhaled by the occupants of the vehicle.
The Washington Post notes that Arizona is a warm climate, so they don’t often use washer fluid with methanol, a de-icing agent that would inhibit the growth of the bacteria.
Further studies will likely be conducted, but for now, choose a brand of windshield washer fluid with a methanol additive, just to be on the safe side.