soap as food for bacteria

In This recent article the lives of billions of bacteria living in your shower curtain are discussed.

Appearantly the funky scum at the bottom of your plastic shower curtain is rife with danger , especially if your immune system is compromised (HIV etc.)

Interestingly though, the sentence “What role soap plays when it mixes with the bacteria also is unclear.” makes me wonder what is meant .

Could soap be a food for bacteria?

Aw c’mon! Nobody?

Hold on there. The article does not say your shower curtain is “rife with danger, especially if your immune system…” Here’s the quote:


Kelly and Pace emphasized that the bacteria they found on their shower curtains normally don’t cause problems for humans. “We don’t want to freak people out, because we’re really only talking about immune-compromised people,” Kelley said.


It’s hazardous ONLY if your immune system is compromised.

By the way, the goop on your curtain, or biofilm, is partly soap, but it’s also a soup of your dead skin cells, hard water flakes, lint, and a smorgasbord of the routine airborne bacteria that roils around us all day long. Frankly, this article echoes of the gee-whiz of first year nursing students who’ve just seen germs through a microscope for the first time.

As the article says, you can toss the curtain in the wash every few weeks. You can also keep a spray bottle of cheapo disinfectact handy, and spritz the curtain every shower or two. If you’re not immunodeficient, you don’t really need to do anything.

You cannot live a germ-free life, nor would that necessarily be a good thing.

They have bacteria that eat sulpher and heavy metals.

Soap would be a dessert for them.

I guess the question is, does the soap disrupt the bacteria’s cell membrane or not. It has been sufficiently long since I got my biology degree (and promptly and purposefully stopped thinking about biology) that I’m not sure soap = detergent. Detergent, I know, disrupts the lipid bilayer. Soap may just attach to the bilayer and to a molecule of water, so the lipid gets washed away. I guess another question is whether soap can do whatever it does without the presence of water–that is, do bacteria thrive differently on wet bars than on dry bars?

In Home Comforts, Cheryl Mendelson recommends that liquid soaps be dispensed from disposable containers, because over time the containers may become infected. It’s therefore good to discard the container often. I think she recommends liquid pump soap for washing hands over bar soap, because it’s cleaner. I guess all of this indicates that bacteria can grow in soap.