Biofilm, Medical Devices, Your Pool or Spa

Last week we talked about biofilm, the microscopic colony of bacteria that lives where water, bacteria and any surface meet.  Scientists who study bacteria in the laboratory have known about biofilm for 10-15 years.  It has taken that long for the laboratory bench research to impact our daily lives and biofilm impacts just about everything.  Think about it:  combine water, a surface and bacteria and you have instant biofilm.

Biofilm: A Slime City

A recent article in the July/August 2009 issue of Discover by Wendy Orent called “Slime City” talked about biofilm and its impact on medicine and implanted medical devices.  She did a great job describing what is known about biofilm and how it causes serious diseases and problems in the body. View the article:  http://discovermagazine.com/2009/jul-aug/17-slime-city-germs-talk-each-other-plan-attacks/?searchterm=Slime

The same biofilm that coats medical devices, your teeth, or an infected bone or wound covers every surface of your pool or spa.  All disinfectants such as chlorine, bromine, ozone, cooper or silver are effective killers of bacteria that swim in the water.  Unfortunately, that’s only 1-2% of the bacteria that populate a pool or spa.  The rest are safely protected from the disinfectants by biofilm.

The colony in biofilm is static.  It is alive just like a city.  The bacteria move, send off microscopic streamers of biofilm containing bacteria to settle on other surfaces, send off microscopic balls of biofilm to roll along the surface to start a new colony, and provide a nursery for bacteria to multiply and replace those that die off.

A Slime City in your pool or spa?

You see the effects of the biofilm streamers when your spa forms foam on the surface of the water.  Biofilm free water in a spa doesn’t foam.  The air bubbles injected into the water from the jets come to the surface and pop.  Biofilm in pools and spas cause the rings and scale on the pool sides.  It also causes cloudy water.

Recently, the scientists at the Center for Biofilm Engineering at Montana State University (http://www.erc.montana.edu/) discovered that biofilm causes corrosion of metals.  At the interface of the metal surface and the biofilm the pH is around 1 and there is a small electrical current produced by the bacteria.  The combination can cause electrolysis of almost all metals.

Think of your spa or pool’s heater cores, motors, seals and metal fittings.  The microscopic biofilm is slowly eating the metal causing mechanical failures that are costly to replace.

The take home message is that biofilm is a major contributor and cause of most problems in pools and spas.  So, how do you get rid of it? Tune in next week for more.

Tags: Biofilm, cloudy water, Discover, foam, pool, spa, Wendy Orent
Posted in Biofilm | No Comments »