“Sanitizing” is different from cleaning. That’s one of the many things people get wrong about removing germs that Purdue experts want consumers to understand.
Amanda Deering, associate professor of produce food safety, and Tari Gary, extension administrator for food science, teach growers how to remove germs from produce, but they also offer tips for sanitizing at home.
What is a sanitizer
“A sanitizer reduces the number of microorganisms on a surface,” said Gary. “It’s different than a detergent or a sterilizer. Detergents just remove visible contaminants, and sterilizers remove all microorganisms.”
How a sanitizer gets approved for use
Because sanitizers are designed to kill microorganisms, the Environmental Protection Agency (EPA) classifies sanitizers as pesticides. “The ‘pest’ are bacteria,” Deering explained.
The EPA regulates manufacturers’ claims about a product’s efficacy, product uses, labeling, advertising slogans, and more. The agency also ensures the product is safe when used as directed.
“Manufacturers have to submit toxicology data,” said Deering. “If the EPA says, ‘Okay, it doesn't look like it would harm anyone,’ then they approve it.”
Once a product gains approval, it receives a unique registration number. The same product may be sold under different names from a company, but the registration number is the same.
For example, a company may have a kitchen sanitizer and a bathroom sanitizer that share an EPA registration number. One item could be marketed as “Kitchen E-Zee Clean” and the other as “Bathroom E-Zee Clean,” but they have the same formula and, thus, the same registration number.
If a product has no EPA registration number and makes a sanitization claim, that’s a red flag.
“There’s a list of about 30 ingredients that don’t have to go through the EPA, like thyme oil and many herbal ingredients, but those products can’t make a claim,” said Deering. “They can't list on the packaging ‘kills 99.9% of germs’ or anything like that.”
If a consumer wants to sanitize with a non-EPA approved product, such as thyme oil or white vinegar, Deering suggests looking for peer-reviewed research papers to see how effective these products are and how they should be used.
How to sanitize, the right way
Sanitizing a surface has three steps:
Each of these steps plays an important role in killing germs and keeping people safe.
“A common misconception is that you can apply a sanitizer to a dirty surface,” said Gary. “To get that full effectiveness promised on the label, clean the surface first, making it as visibly clean as it’s going to get. Then, apply the sanitizer. If you don't do that, the sanitizer is going to be used up before it gets down to the surface.”
After cleaning, and before sanitizing, people should always review the product’s label first. Otherwise, they could endanger themselves by not taking proper precautions.
“Stick to the label,” Deering cautions. “Some people say, ‘A little is good, but a lot is better,’ but that’s not true with sanitizers. If you don’t follow the label, there’s a real risk of using the sanitizer at too high a concentration or using a sanitizer for an unintended purpose.”
For example, Deering recalls one time a woman contacted her after a sanitizer made her skin turn white. “In the past, she had bought a diluted version of the sanitizer, but she accidentally bought the same product with a higher, almost dangerous concentration,” Deering said. Thankfully, the woman was okay, and the effect was temporary. The situation might have been avoided, however, with careful label reading.
Special considerations for food surfaces
Consumers should pay special attention to labels if they plan to sanitize a food-contact surface. Common sanitizers like sanitizing wipes or aerosol disinfectant sprays work well for many household needs, but they may not work for food-contact surfaces.
“The danger is that you could ingest harmful ingredients from the sanitizer,” Gary explained.
Even if a product is approved for food-contact surfaces, consumers should pay attention to what microorganisms the product is designed to kill. For example, a product label showing “kills Salmonella” would make sense to use after cooking raw chicken but not if the consumer was concerned about Listeria.
“Just look at the label,” Deering said. “Before you use any sanitizer, make sure it’s labeled, especially if you want to wash or sanitize a food contact surface. You have to be careful what you're using.”