It’s time to wipe down those spice containers in your kitchen cabinets. They may be loaded with bacteria. That is the result of a new study from a team of researchers from Rutgers University along with North Carolina State University colleagues who found that these common kitchen containers post an increased risk for bacterial cross-contamination.

According to Study Finds, researchers discovered that nearly half of the spice containers in a cooking experiment had been contaminated with a pathogen when participants cooked the same meal in different sized kitchens. This was a higher level than the number of germs the study subjects transferred to cutting boards and trash can lids during the study.

“In addition to more obvious surfaces like cutting boards, garbage can lids, and refrigerator handles, here’s something else that you need to pay attention to when you’re trying to be clean and sanitary in your kitchen,” said Donald Schaffner, a professor and extension specialist in food science, who co-authored the study. “Our research shows that any spice container you touch when you are preparing raw meat might get cross-contaminated. You’ll want to be conscious of that during or after meal preparation.”

According to a Rutgers’s University news release, foodborne illnesses such as salmonella and campylobacter account for nearly two million infections each year in the U.S. A large portion of these illnesses come from chicken, turkey, beef, pork, and game. Scientists say that proper handling of food, including adequate cooking, consistent hand washing, and sanitizing kitchen surfaces and utensils can combat cross-contamination.

“The purpose of this study was to determine the prevalence and degree of cross-contamination across a variety of kitchen surfaces during a consumer meal preparation,” said Schaffner. The researchers monitored the behavior of 371 adults who cooked the same recipe for spiced turkey burgers in several kitchens, ranging from small apartment-sized galleys to large teaching kitchens in extension centers and food banks.

Prior to food prep, the researchers injected the ground turkey with a pathogen called MS2 to serve as a tracer. The study participants were not informed that the researchers would be examining their food safety behaviors until after they prepared the meal, says the news release. Then researchers swabbed kitchen utensils, cleaning areas and kitchen surfaces to test for the presence of the MS2 tracer.

But while watching the participants prepare the turkey burgers, they also decided to add new surfaces, such as spice containers and kitchen sink faucet handles, to the surfaces examined. Surprisingly, the researchers found that the most frequently contaminated objects were the spice containers, with about 48% of the samples showing MS2 contamination.

“We were surprised because we had not seen evidence of spice container contamination before,” said Schaffner. “Most research on the cross-contamination of kitchen surfaces due to handling of raw meat or poultry products has focused on kitchen cutting boards or faucet handles and has neglected surfaces like spice containers, trash bin lids and other kitchen utensils. This makes this study and similar studies from members of this group more comprehensive than previous studies.”

The study was commissioned by the U.S. Department of Agriculture’s Food Safety and Inspection Service.