The Bacteria Lurking in American Showerheads – Interesting Article we found

Interesting Article by

Rob Dunn

“In 1654, Rembrandt painted a woman, in Amsterdam, bathing in a stream. As she lifts her nightdress above her knees and treads deeper, the woman is stepping from one world into another. Among art historians, the transition she is making is metaphorical. But to a biologist, it is also ecological.

We imagine water to be clean, and we imagine clean to mean lifeless, and yet all the water you have ever bathed in, swum through, or drunk has been full of life, from bacteria to tiny crustaceans. So, too, the pipes in which it travels. As water passes through pipes in general and showerheads in particular, a thick biofilm builds up. Biofilm is a fancy word that scientists use to avoid saying “gunk.” It is made by individuals of one or more species of bacteria working together to protect themselves from hostile conditions—including the flow of water, which constantly threatens to wash them away—via their own excretions.”

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This is a very timely article – we work with a lot of private water systems, public water supply systems, and businesses that have a biofilm problem and to be honest I have had this problem in my home (s) that were serviced by both city water and well water.

First Step – Learn

  1. Biofilms and Bacteria – bacteria does not normally grow free-living in the drinking water, but attached to the piping or surfaces within the system as a biofilm.  This microbiological community can include a variety of organism that may be aerobic (like or need oxygen), anaerobic (low oxygen), or facultative(in the middle).  The bacterial coating may be clear or discolored, create odors, contain trace metals, or promote microbiologically induced corrosion.  The bacteria can impact the quality of the drinking water and the integrity of the distribution system.  When people test city or well water, they normally only test for total coliform bacteria and may be E. coli., but that is not enough.

Second – Diagnose

  1.  The next step is to diagnose, but diagnose is really using a combination of observations and testing to determine if there may be a problem or concer.
  2. We recommend the following:
    • Visually inspect the plumbing – look in the back of the toilet tank is the wall discolored, if discolored does it feel slimy,  look in the bathroom do you see films or coating on showerheads or other surfaces.  If you have any clear tubing, does the tubing have any observable films or coatings.  If you have a particle filter, does it feel slimy.
    • Are there any odors or strange smells to the water.
    • If the water sits, does it have a floating metallic sheen on the surface.
    • Have you been experiencing problems with discolored water that is black, brown, or even greenish blue?
    • Flush the water heating tank – what do you see?
  3. If you observe a film or coating, you may have a biofilm problem.
    • If the bacteria is pink, this may be  Serratia marcescens.   This is typically an airborne bacteria and we suggest that you wash the services with an anti-microbiological cleaner,  monitor and control the humidity of the room, regularly clean the surfaces, wipe down showers after use, and keep the ventilation fan running for at least 20 minutes.
  4. The next question is do you have any health issues?
    • If health issues are gastrointestinal and you have slime coatings  – We recommend testing for total coliform, E. coli., and slime forming bacteria, and standard plate count.
    • If you do not have health issues, but have slime coatings with discolored water, we would recommend total coliform, iron related bacteria, slime forming bacteria, and standard plate count.
    • If you major health issues that include respiratory issues with or without gastrointestinal issues we recommend total coliform, E. Coli, and Waterborne Pathogen Panel.


Third Step – Test/ Monitor

  1.  Testing can include a variety of measures that include:


Filed under Children's Health, Community Health, environmental education, Environmental Hazards, Home Inspectors, Homeowner, Uncategorized, Water Testing, Well water testing · Tagged with , , , , ,

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