Where in your kitchen do you find coliform and Staph bacteria, yeast, and mold?If you guessed your sponge or dish cloth, you’re right.According to the NSF International survey of U.S. homes 77% of sponges and dish cloths contained coliform bacteria, 86% had yeast and mold, and 18% were contaminated with Staph bacteria. These organisms can cause nausea, vomiting, abdominal cramps, diarrhea, headaches, and general fatigue.Nearly one in four of us keep sponges until they look dirty or smell bad, while 17% wait until sponges fall apart before throwing them out. Another 18% say they typically keep their sponges for three to four weeks, while 8% keep them for a month or longer. A damp, smelly dish towel, cloth or sponge is a sure sign that unsafe and potentially harmful bacteria are present and growing.The FDA Food Code, the Food and Drug Administration’s best advice to promote safe food in retail and food service, does not allow sponges to be used in restaurants. Sponges contain hundreds of nooks and crannies where bacteria can multiply, and the wet environment on a sponge promotes rapid bacteria multiplication. Rinsing and squeezing out the excess water from a sponge doesn’t remove bacteria picked up from your countertop, stove or refrigerator. Instead of sponges, restaurants and food retail operations use dish cloths that are kept in a bleach solution and laundered daily.How to clean and sanitize your kitchen spongesThe most effective way to kill 99% of the bacteria lurking in your kitchen sponge is by microwaving a wet sponge at full microwave power for 1 minute. Be sure the sponge is wet before microwaving or it may catch fire!You can also run your sponge through the dishwasher. Soaking sponges in a 10% bleach solution, which is about twice as concentrated as household bleach, is not much better than doing nothing.Even better: use a clean dish cloth each time you clean your kitchen countertops and eliminate sponges completely. After each use, toss the dish cloth in the laundry and run it through a hot water cycle on your washing machine. Dry the dish cloths thoroughly in a hot dryer.Additional tips to keep your kitchen safe from bacteria:

• Store sponges in a dry location away from the sink to keep harmful bacteria from quickly multiplying.
• Even when you microwave or launder your sponges every day, replace them at least monthly.
• Use a paper towel to wipe up meat juices and then spray the counter with disinfectant and wipe up with another clean paper towel.

The #1 way to prevent foodborne illnesses in your kitchen is to wash your hands as the first step in all food preparation. If you already wash your hands consistently, take the next step by making sure your kitchen sponges and dish cloths are clean and sanitary.By Lynn Grieger RDN, CDE, CPT, CHWCReferences

1. Center for Science in the Public Interest. The Dangers of Dirty Sponges and Dish Cloths. https://cspinet.org/tip/dangers-sponges-and-dish-cloths-kitchen-safety-cross-contamination Published 6-27-16; accessed 7-10-18
2. Michigan State University Extension. Keep Your Sponges and Dish Cloths Bacteria-Free This Summer. Lisa Treiber. http://msue.anr.msu.edu/news/keep_your_sponges_and_dish_cloths_bacteria_free_this_summer posted 7-20-16, accessed 7-10-18
3. Texas A&M Agrilife Extension. Food Technology and Processing. Introduction to the Microbiology of Foods. https://aggie-horticulture.tamu.edu/food-technology/food-processing-entrepreneurs/microbiology-of-food/ Accessed 7-10-18
4. U.S. Food and Drug Administration. 2017 Food Code. https://www.fda.gov/downloads/Food/GuidanceRegulation/RetailFoodProtection/FoodCode/UCM595140.pdf
5. Sharma, Manan & Eastridge, Janet & Mudd, Cheryl. (2009). Effective household disinfection methods. Food Control 20(3) · March 2009. DOI: 10.1016/j.foodcont.2008.05.020

PDF Handout: Food Safety