These Are the Filthiest Places In Your Kitchen

May 11, 2017
TIME Health
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You're right to be wary of restaurants with less-than-perfect scores from the health department, but chances are good that your own kitchen is a hotbed of germs, too. New research from Drexel University shows that, if held to the same standards as commercial eateries, most homes would be slapped with major food-safety violations.

“When people get sick from food-related issues, they often think back to the last time they ate out,” says study co-author Jennifer Quinlan, associate professor in Drexel's College of Nursing and Health Professions.. “But contamination in the home definitely leads to a certain amount of those illnesses.”

When a team of researchers visited 100 homes in Philadelphia from a wide range of socioeconomic backgrounds, they found evidence of pest infestation, improper food storage, and disease-causing bacteria in many kitchens. Their findings are published in two new studies in Food Protection Trends and the Journal of Food Protection.

“We were able to find actual pathogens that we know people get sick from,” says Quinlan—pathogens like staphylococcus aureus, salmonella, campylobacter, and listeria. “And we were able to isolate these pathogens from essentially all over kitchens, including inside refrigerators, on refrigerator door handles, on counters, in sinks and on sponges.”

Here are five areas that raised the most red flags for the researchers:

1. Your fridge
The biggest mistake noted in the study—seen in 97% of homes—was that raw meat or poultry was improperly stored. It should always be on the lowest shelf in the refrigerator, below ready-to-eat foods and raw fruits and vegetables. As gross as it sounds, juices from your raw chicken could drip down and contaminate other foods.

Refrigerators should also be kept at or below 40 degrees Fahrenheit, according to the U.S. Food and Drug Administration, but 43% of those in the study registered higher than that. Refrigerators with higher operating temperatures were linked with higher counts of listeria, a bacterium that’s especially dangerous for pregnant women, older adults and people with weakened immune systems.

2. Your dishcloths and sponges
About 45% of households surveyed contained at least one foodborne pathogen, and compared to other areas of the kitchen, sponges were the grimiest: 64% tested positive for bacteria.

“These things are reservoirs for bacteria," says Quinlan. "And even worse, if we found staph or fecal coliforms in your sponges or your dishtowels, it was more likely we would find them elsewhere throughout your kitchen. If you’re using them to clean your counters and other areas, the bacteria’s going to spread.”

Quinlan recommends washing dish towels often, and only using them to dry clean hands and dishes. Microwaving kitchen sponges for one minute a day—or running them through the dishwasher—can also kill harmful pathogens.

3. In and around your sink
Fecal bacteria were found in 44% of the kitchens, and E. coli, a related bacterium, was found in 15%—most often in samples from kitchen sinks. “If it’s wet, it’s more likely to be nasty,” says Quinlan.

Kitchen sinks were also the most likely spot to be visibly dirty: The researchers rated 82% of the sinks they visited as unclean. Kitchens that lacked sanitizer, disinfectant products, or soap near the sink also tended to have higher bacterial counts overall.

4. Cutting boards
Because so many different foods are prepared using cutting boards, it’s important to clean them between use and be sure no contaminants—from raw meat or unwashed produce, for example—are left behind. But 23% of the cutting boards observed in the study appeared dirty, and 76% were worn with deep grooves or cracks in the surface, where bacteria could potentially hide.

Potentially just as risky, 49% of homes in the study did not appear to have cutting boards in the kitchen at all. “Anecdotally, this could indicate that people are preparing all different types of food, including raw meat and poultry, right there on the counter,” says Quinlan.

5. Anywhere pests—and your pets—hang out
Researchers observed insects, like ants, roaches, and flies, as well as rodent droppings or bug traps in 65% of homes. The presence of animals—including household pets— in food-preparation areas could also increase the likelihood of food contamination and the transmission of outside pathogens into the kitchen.

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