Household Disinfection 101

Spring cleaning time is here again and many penny-wise consumers are choosing to mix their own cleaning and disinfecting solutions to help stretch the household budget. The Water Quality & Health Council would like to help consumers make good choices as they tackle their disinfecting chores.

Cleaning Is Not the Same as Disinfection

Cleaning and disinfecting are different tasks with different goals. In cleaning, water and detergent—and often a healthy dose of elbow grease—are used to help remove dirt and grime from surfaces. The goal of disinfection is to destroy germs. After cleaning food-contact surfaces, such as the kitchen counter, it is important to disinfect. For many consumers, the question is: What is the most effective product to use to disinfect? Bleach, hydrogen peroxide, vinegar, lemon or lime juice and baking soda are some of the products suggested for use, but just how effective are they in destroying germs?

A few years ago, a team of scientists asked that question and designed experiments to rate the performance of five common household products against foodborne bacteria.1 The bacteria, E. coli O157:H7, Salmonella and Listeria monocytogenes, are frequent culprits in foodborne disease outbreaks and may be found as contaminants in food products brought into the home, including vegetables, cheeses, ice cream and raw meat. The scientists noted that these bacteria can survive on food contact surfaces for hours or even days at a time. Contaminated surfaces may harbor bacteria that can then cross-contaminate other foods.

Research Findings

The researchers found that of the five products tested, only a diluted solution of chlorine bleach was effective against all three of the common kitchen germs. Baking soda had no detectable effectiveness against the trio of test germs. For this analysis, product effectiveness was compared after one minute of exposure to germs at room temperature. The table below summarizes the research findings.

Disinfecting Surfaces with Common Household Solutions

(Based on Yang et. al, 2009; all trials included application at room temperature

during which solution was left on surface for one minute.)

Most Effective

Arrow

Least Effective

Household Substance Mixing Directions Notes
Chlorine bleach

(0.0314% sodium hypochlorite)

1 tsp. bleach + 1 qt. water Make fresh solutions daily as bleach breaks down over time; degrades into mostly salty water as it destroys germs. Effective at room temperature.

Do not mix bleach solution with other products.

Hydrogen peroxide (3%) undiluted Use freshly poured product within a short period of time; degrades quickly into oxygen and water when exposed to light.
White vinegar

(5% acetic acid)

undiluted
Lemon/lime juice

(5% citric acid)

undiluted
Baking soda

(50% sodium bicarbonate)

Ineffective as a disinfectant

Disinfection Efficacy of Common Household Products at Room Temperature and One-Minute Exposures

(Based on Yang et. al, 2009)

Listeria monocytogenes Escherichia coli Salmonella Typhimurium
Chlorine bleach destroys…

*Hydrogen peroxide destroys…

*White vinegar

*Lemon/lime juice
Baking soda

*Yang et. al (2009) found bacterial reductions of Listeria monocytogenes were possible using these substances when they were applied at an initial temperature of 55 C for 10 minutes at a time.

1 Yang, H., Kendall, P.A., Medeiros, L. and Sofos, J.N. (2009). Inactivation of Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella Typhimurium with Compounds Available in Households. Journal of Food Protection, v. 72, No. 6, pp. 1201-1208.

Linda Golodner is President Emeritus of the National Consumers League and Vice Chair of the Water Quality & Health Council.

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