An analysis of 50 showerheads from nine U.S. cities found that about 30 percent harbored high levels of Mycobacterium avium -- a group of bacteria that can cause lung infections when inhaled or swallowed.
via www.reuters.com
I am sure I am not the only one who reads this study and then wants to go directly and clean their shower head. By the way - what you should do is periodically remove the shower head and soak it in a cleaning solution for getting hard water stains off.
How to clean a shower head? I use something CLR diluted with water. If you have to remove the shower head wrap it in a towel before using pliers or wrench to protect the chrome finish. Some people just use vinegar. I am sure that bleach would kill the mycobacterium, but one of the other benefits of cleaning your shower head is getting the mineral deposit buildup out of the holes so none of them are blocked up.
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