BOB HIRSHON (host):
Bugs in the shower. I’m Bob Hirshon and this is Science Update.
The whole point of a shower is to get clean, which makes a recent study especially squirm-inducing. Microbiologist Norman Pace and his colleagues at the University of Colorado at Boulder found potentially harmful bacteria inside shower heads at 100 times the concentrations found in tap water. Pace notes that these bugs can hitch a ride on water vapor particles when you turn the shower on.
NORMAN PACE (University of Colorado at Boulder):
Many aerosols that are generated by a shower head have particle size in the 20 micron range, and that’s small enough to penetrate the deep airways, and also carry along any bacteria that happen to be entrained.
The chief concern is Mycobacterium avium, a lung pathogen that mainly affects people with weakened immune systems. If that includes you, Pace suggests using a faucet-like shower head that minimizes spray, or just taking a bath instead. I’m Bob Hirshon for AAAS, the Science Society.