The weekly dose: is vinegar an effective household disinfectant?

{Once a week we will examine the evidence pertaining to a health-related matter-- usually something that would be of interest to families with young children.  You should expect a thought out and concise summary of the issue along with several solid references-- there may or may not be a true conclusion.  Sometimes, “more research is needed”  really is the best answer that can be given.  Please leave me a comment if you have thoughts, questions, or another topic idea that you’d like addressed.}

The question of whether vinegar is an effective household disinfectant is an important question by itself, but it is also closely linked to the question of how important it is to actually have disinfected homes.  But perhaps that’s a question for a different day.

So, the question for this week: is vinegar an effective household disinfectant?

Australia's ABC Health and Wellbeing posted a reasonable article answering the question, "Does vinegar really kill household germs?".  They concluded that it does, but not as well as commercial products.  However, in classic fashion, I wanted to know what the original research had to say about this.

Most of the research that I found centered around disinfecting produce or chicken, but this still seems relevant since they compared the vinegar to other disinfectants, which usually included bleach.

Searching PubMed for "vinegar disinfect*" I came up with 878 results.  Limiting the studies to humans and studies published in the last 5 years reduced that number to 64, but to be honest this probably wasn’t the best search.  One interesting result that did show up was a study about Salmonella on Chicken breasts (1).  This would at least be applicable in the kitchen.  This study found that 0.2 mg/mL thymol (which is found in Thyme oil) plus 2 mg/mL of acetic acid (vinegar) was just as effective in reducing the Salmonella as a chlorine-based washing solution on contaminated chicken breast meat.   However, the huge draw back to this study is that they didn’t compare the acetic acid and thymol mixture to a simple acetic acid solution, so it’s unclear to me how much of a difference the thymol actually makes.

On an unrelated note, Amazon apparently sells thyme oil, but I’m not sure what the actual concentration of thymol inside the thyme oil would be.  I wonder if the thyme oil would make vinegar smell better though.  Hmm.  Maybe I’ll have to try it. 

Changing the search terms to “domestic surfaces disinfect*” seemed to pull up more relevant results.  Unfortunately, most of the results still seemed to center around food.  One study looked at knifes and bell peppers inoculated with Salmonella and e. coli(2).   They compared 3% hydrogen peroxide, 2.5% acetic acid, 70% ethyl alcohol (wine is usually 12-15% ethyl alcohol), and sterile distilled water for decontamination of the bell peppers.   The study concluded that ethyl alcohol and hydrogen peroxide may be effective antimicrobials for in-home decontamination of peppers, and that use of detergent and warm water is effective for decontamination of knifes used during meal preparation.  The authors of this study explain that it is important to pay attention to disinfecting food in the home since it is possible for food outbreaks to occur even in the home.  In 2008 15% of food outbreaks with a known origin came from a home.  This was a good reminder to me, that this really does matter for me in my home. 

Perez, et al. included a insightful figure (see below) looking at the length of exposure a disinfectant and the corresponding efficacy of the different disinfectants that clearly shows that the length of time the bell pepper was exposed to the disinfectant greatly influenced the efficacy of the disinfectant.  Even though alcohol appears to be the best disinfectant in the shortest amount of time, the authors recognize that many people might not be comfortable with such an elevated concentration of alcohol, and because of this they suggest the use of hydrogen peroxide with an application time of 5 minutes.

Perez et al., Figure 1

So, where does all this leave me? Is vinegar an effective household disinfectant?  It does appear to be effective against Salmonella and e. coli.  Since all the studies I found focused in the kitchen, I’m not comfortable generalizing these conclusions to the bathroom (I’m guessing there’s a different set of organisms in there), but as far as the kitchen goes, vinegar appears to be at least mildly effective.  I’ll probably start using it occasionally.  However, since I’m not interested in using alcohol, as Perez et al. suggested, I think I’ll start disinfecting the kitchen and my produce with hydrogen peroxide-- it smells better than vinegar anyway.

(1) Lu Y, Wu C. 2012. Reductions of Salmonella enterica on chicken breast by thymol, acetic acid, sodium dodecyl sulfate or hydrogen peroxide combinations as compared to chlorine wash. Int J Food Microbiol. 152(1-2):31-4. doi: 10.1016/j.ijfoodmicro. Accessed from: http://www.ncbi.nlm.nih.gov/pubmed/22030209.
(2) Perez KL, Lucia LM, Cisneros-Zevallos L, Castillo A, Taylor TM. 2012. Efficacy of antimicrobials for the disinfection of pathogen contaminated green bell pepper and of consumer cleaning methods for the decontamination of knives.Int J Food Microbiol. 2012 May 1;156(1):76-82. doi: 10.1016/j.ijfoodmicro.2012.03.012. Accessed from: http://www.ncbi.nlm.nih.gov/pubmed/22476008.