It's natural to expect that the water coming out of our taps is safe without worry of gastrointestinal or other infectious disease. Yet every year there are dozens of outbreaks linked to drinking water in the United States alone. In the majority of cases, a failure of proper water treatment is the cause. But there is an increasing theory that the problem may not be caused at the source, but rather in the house by a handful of microbes living in the pipes behind your walls.
While we may all believe that the chemicals used in our water treatment are effective against all germs, there is a different reality. Many waterborne disease-causing bacteria, viruses and parasites are resistant to the low levels of chlorine and other disinfectants used in the treatment process. They live quite happily in the plumbing system of the home and form their own tiny cities -- called biofilms.
When formed, biofilms invite other germs to become part of the community and then, as an added bonus, helps them to hide away from the disinfectants that would normally kill them. Then, due to some type of change in the water flow or other disturbance, pieces of the biofilm will break off, grab the current and find its way into your mouth, into your lungs or onto your skin.
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