At first glance the term soap scum seems like an oxymoron along the lines of jumbo shrimp or airline “food.” But unlike rubber chicken served at 35,000 feet, soap scum is not an oxymoron. It is technically misnamed; it is neither soap nor scum.
The filmy layer of mildew that forms on shower curtains, sinks, and tubs is not caused by soap but by minerals in water, especially hard water. These minerals, primarily calcium and magnesium, combine with soap to create a sticky mixture which bonds with bathroom surfaces. Now the gross part: soap scum also includes body oils, dead skin, hair, and whatever dirt may be floating around your tub. It gets worse: the white to grey colored soap scum is irresistible to mold and algae. When these furry beasties attach themselves to the scum, it can turn the colors of the rainbow and emit smells that are unpleasant.
It goes without saying; you don’t want this gunk to build up over weeks, months, and years. And the longer it is allowed to grow, the harder it is to remove. Fortunately there are ways to deal with soap scum. First, clean bathroom surfaces regularly; wipe down tubs, showers, sinks, and tile at least once a week. A cream cleanser like Soft Scrub with Bleach Cleanser will instantly cut through the film and kill mold and mildew. You should also remember to wash your shower curtains and bathmats regularly. Toss them in the washing machine on the gentle setting with a half cup of vinegar.
If you have soap scum that has built up over a long period you might need to get out the heavy artillery. Commercial degreasers will cut through the scum in no time. Be sure to wear rubber gloves, open the windows, and turn on the bathroom fan when using heavy-duty cleaning products.
Soap scum is a particular problem for those who live in regions with hard water. For a long term solution to soap scum, install a water softener and replace your plastic shower curtains with a glass enclosure.