Even the tidiest kitchens might be harboring harmful bacteria, and often where they’re least expected. Paying more attention to a few often-overlooked places can help keep your household safer, experts say.

For starters, home cooks should have four watchwords, according to the Centers for Disease Control and Prevention: clean, separate, cook and chill. Watch for cross-contamination, particularly with meats and vegetables; cook everything thoroughly; and keep both raw and cooked foods sufficiently cold when needed.

Then, cleaning a few often-overlooked areas in the kitchen could offer additional protection from E. coli, salmonella, listeria, yeast and mold, according to NSF International, a nonprofit organization based in Ann Arbor, Mich., that has been promoting proper cleaning of kitchen tools and appliances since the 1940s. NSF International has put out recommendations on kitchen hot spots based on studies done in 2011 and again in 2013:

Scary sponges — “You can either get away from sponges altogether and use dish cloths or rags, which can be sanitized, or, if you do use sponges, put a wet sponge in the microwave for 2 minutes to kill most of the harmful bacteria,” said Lisa Yakas, a microbiologist with NSF. Betsy Goldberg, home director for Real Simple magazine, said, “Many people mistakenly think that rinsing a sponge with water is enough, but sponges really need to be washed in the top rack of the dishwasher or wet and then microwaved for 2 minutes,” and “obviously, if it smells or has loose pieces, it’s time to throw it away.”

Ghastly gaskets — Dangerous beasties can lurk in the hard-to-reach areas under the thin, removable plastic gaskets found around the lids of some food storage containers, and also around blender gaskets and blades, according to Yakas. “This one people really find surprising. But think about how many times people make smoothies and just put the blender in the dishwasher or rinse it then use it again. In our studies, we found salmonella, E. coli, yeast and mold around blender blades and gaskets.” She recommends unplugging blenders, flipping them over and unscrewing the blade assembly, then washing all the parts and drying them thoroughly after every use. For food storage containers, any unattached gaskets should be removed, cleaned and dried after every use, Yakas said.

Creepy fridge compartments — “Meat and vegetable compartments are another place few people think about, but it’s where you are storing raw meat and vegetables that may still have some soil residue,” Yakas said. “Keep everything raw and cooked separately, and remove the compartments and wash them with warm soapy water about every two or four weeks, depending on your household needs.” Goldberg suggests removing them every so often and soaking them in the sink in hot, soapy water for 15 minutes. “While they are soaking, you can douse the inside of the fridge with a disinfecting spray,” she said. “Wipe down the walls and then each shelf, and use a toothbrush spritzed with cleaner to get in the crevices. After 15 minutes, drain the water and sprinkle the compartments in baking soda, then wipe them clean with a wet sponge.”

Separate the spatulas and clean the can opener — Can openers should be washed in the dishwasher or at least hand-washed after every use, paying attention to removing any food residue on the blade, Yakas said. “And a lot of people are surprised to find that a lot of spatulas and scrapers are actually composed of two pieces that pull apart, and that the inside part can harbor salmonella, E.coli and yeast,” she said. “Just pull it apart, clean with soapy water, rinse and thoroughly dry.” Goldberg said, “Ideally, if you have time, it’s a good idea to go beyond the can opener and spatula parts, take all the tools out of your drawer and wipe the inside of the drawer and the utensil holders with a disinfecting wipe, then dry it all thoroughly.”

Wash water dispensers and coffee reservoirs — “Our studies found yeast and mold in refrigerator water dispensers, which might be an issue for people with allergies,” said Yakas. Most systems can be cleaned with a vinegar solution, she said. “Coffee machine reservoirs are also dark and damp and are great places for mold and mildew to grow,” she said.  “It’s a good idea to pour about 4 cups of white vinegar in the reservoir and run the vinegar through the unit, followed by two to three wash cycles of water. This should really be done every 40 to 80 brew cycles, or at least monthly,” she said.