The shower head provides a warm, moist, dark environment for microbes to grow. And when the tap is turned on, it carries away those potential pathogens and releases them in the form of aerosols, which are easily inhaled and enter the lungs.
Norman Pace and his colleagues from the University of Colorado visited 45 homes in 9 cities in the United States to analyze the contents of their shower heads. They then compared it with the microbes present in the water before reaching the tap, and concluded that the concentration of pathogens is 100 times higher inside the shower head than in the water that reaches it . Among the bacteria identified, Mycobacterium avium stands out, a relative of the tuberculosis pathogen present in significant concentrations in 1 out of 5 showers, as published today in the journal P NAS . Researchers have also detected the presence of Sphingomonas and Methylobacterium .
The study authors recommend investigating how this problem affects people with respiratory difficulties or weak immune systems, such as patients with AIDS or cancer and patients who have just had an organ transplant, who perhaps should be advised not to use the showers.
