Monthly Archives: June 2014

The Truth about Showering Safely

Let’s be truthful – taking a warm shower can be a great way to revitalize yourself in the morning and unwind after a long day. If you aren’t careful, however, it could also make you very sick. Certain disease-causing bacteria, such as Legionella pneumophila, feel right at home in our showerheads due to a regular supply of warm water and their ability to create nearly impenetrable protective biofilms. In layman’s terms, these nasty bacteria have the ability to build a slimy “wall” that keeps the chlorine in our tap water from killing them. And with a regular supply of the warm water that they need to happily grow and reproduce, your showerhead seems eerily similar to a Petri dish.

According to the National Institute of Health, the water droplets created when we take a hot shower contain a fairly significant fraction of respirable, aerosolized particles that these bacteria attach themselves to and use to hitchhike a ride into our lungs. This means that choosing to shower when we bathe can actually increase our risk for developing diseases such as Legionnaire’s Disease or Pontiac Fever, which are caused when Legionella pneumophila makes its way deep into our lungs on aerosolized water droplets. According to the CDC, Legionella pneumophila is one of the most frequent causes of water-borne disease among humans in the United States, with as many as 18,000 people infected per year. Legionellais mainly spread by warm water droplets, such as those encountered while showering, and is not communicable person-to-person.  Breathing through one’s mouth while showering can exacerbate this issue, as a significantly higher portion of these aerosolized particles make it all the way to the alveolar region of our lungs when doing so. However, there are far more effective ways to reduce one’s risk of developing Legionnaire’s Disease than remembering to breathe through the nose.

The most effective ways to reduce the likelihood of encountering Legionella pneumophila when you shower are simple. Firstly, be sure to regularly dismantle, clean and descale your showerhead to ensure than any bacterial biofilms that have accumulated are removed. Choosing an easy to clean metal showerhead over a plastic one is also a pretty good idea (and don’t forget to choose a low-flow showerhead to save water). Secondly, check your hot water heater setting to ensure that bacteria cannot easily grow within the hot water system itself, as any source of stagnant, warm water (hot tubs, water-heaters, etc.) creates the ideal environment in which this bacteria can thrive. The Occupational Health & Safety Administration (OSHA) recommends maintaining domestic water heaters at 60°C (140°F) and water delivered at the faucet at a minimum of 50°C (122°F) to ensure that growth of Legionella is kept to a minimum. As a faucet temperature of greater than 120°F can scald an infant, parents of small children will need to be considerate of not relying on water temperature, alone, to control bacteria.

Showering can be a great way to relax, particularly when you can rest easy knowing that you have taken the steps to ensure that you are doing it safely!