The shower head retains and accumulates, over time, mycobacteria responsible, among other things, for the development of sometimes deadly pulmonary infections.
When you attack your bathroom, you usually do not skimp on the household and disinfectants. Soils, sinks, shelves, windows, windows ... everything goes. However, a place escapes systematically to our vigilance: the shower head. And great harm we do, according to a new study, published in mbio.
Although it is only in contact with water, the shower head retains and accumulates, over time, mycobacteria responsible, among other things, for the development of sometimes fatal pulmonary infections (lung disease with non-tuberculous mycobacteria ( MNT) Shower heads often house "abundant mycobacterial communities whose composition varies according to geographical location, water chemistry and water source," say the researchers. that makes bacteria travel from the shower head to the lungs.
To reach these conclusions, scientists analyzed last year the DNA of more than 650 showerheads used in the United States and in 13 European countries. DNA sequencing made it possible to determine which species of bacteria were the most abundant.
Plastic shower heads
The researchers found that deadly mycobacteria were more prevalent in showers in US urban households than in Europeans. Curiously, households whose water was treated with chlorinated disinfectants had a particularly high number of mycobacteria.
"There is a fascinating microbial world that thrives in your showerhead and you can be exposed to it every time you wash," said Noah Fierer, director of research. "This kind of research helps us understand how water treatment and plumbing materials can change the makeup of these microbial communities," he adds. His team found more mycobacteria in metal shower heads than in plastic shower heads.