What Exactly Is Bleach, and What Makes It Such a Good Cleaner?

(Image credit: Hayley Kessner)

You’ve probably heard the phrase, “If it ain’t bleach, it ain’t clean!” While bleach is a go-to cleaner in bathrooms nearly everywhere, it’s a lot more controversial in the kitchen, because there are big pros (majorly antibacterial!) and cons (contact with bleach can be harmful to your eyes, skin, and more, and if a kid or pet ingests it, they can become very, very ill).

Before you think about using — or banning! — bleach in the kitchen, it’s worth understanding exactly what it is, and why it’s such a good cleaner.

What exactly is bleach?

“Bleach” is a word commonly used to refer to a whole category of products. “Bleach simply refers to a product that lightens the color of things through the action of oxidation,” says Nancy Bock, senior vice president of education at the American Cleaning Institute. “However when most people refer to cleaning with bleach, they are thinking of household-strength chlorine bleach, a solution of sodium hypochlorite manufactured from chlorine.”

But don’t let “chlorine” freak you out either. The chemicals in bleach are often derived from chlorine, very early in the manufacturing process. So the bleach you’d use for cleaning in your kitchen is very different than the stuff that’s commonly associated with cleaning pools. Plus, when household bleach is used, it breaks down to mostly salt and water.

How does bleach work?

Bleach, made up of chemicals such as sodium hypochlorite and calcium hypochlorite or hydrogen peroxide for color-safe use, cleans through the process of oxidation. For us non-science-minded folks, oxidation is a chemical reaction that breaks existing chemical bonds to lighten stains, kill various bacteria and microorganisms, and react with dyes and other coloring agents to whiten.

What’s the right type of bleach for cleaning?

You can find bleach in all kinds of products, from laundry detergents to teeth whiteners to cleaning products targeted towards areas like the bathroom and kitchen. Not all products that carry bleach have the same cleaning power, though. “Some products, like scented bleaches, are not registered disinfectants. If you’re looking for a disinfectant, make sure the product label says ‘disinfects or kills germs’ and shows a registered EPA number,” says Bock.

When should you avoid bleach?

“Bleach is most effective on stains from food, drink, perspiration, bodily fluids, and grass in fabric,” says Bock. It can be used to kill bacteria like Listeria, Salmonella, and E. coli on hard surfaces, but isn’t effective on porous surfaces like wood or wallboard, and can damage some surfaces. Don’t use it around kids or pets, as they can hurt themselves if they ingest bleach, get it on their skin, or in their nose or eyes.