Is bar soap hygienic?

As a result of the recent outbreak of Coronavirus (Covid19), discussions on hand washing are high on the agenda and people want to know what are the best hand wash products and methods to prevent and manage build-ups of harmful bacteria. Part of that discussion leads to questions around the re-use of soap bars. 

soap bar in a soap dish

In recent years, the popularity of liquid soap over a more traditional soap bar was driven partly by people’s perception of soap bars being less hygienic. It is a common misconception that germs remain on the soap’s surface after use and therefore are passed on to or from another person. And some of it is true as half of human cells are estimated to be bacteria and a high concentration of this bacteria is found on your skin 1. But of course, your own bacteria will not make you ill.

But what about any unpleasant external bacteria or viruses that may be passed onto the bar of soap from for example another person? In short, you should not be worried. In this blog post we bring you some of the facts and best practices of soap bar use that are based on available research around hand washing which you might find useful when wondering about the effectiveness of soap bar.

How does soap clean?

soap bubbles

Using soap bars has proved to be an effective method of controlling dangerous bacteria for nearly all of recorded human history.

The process of washing with soap is in itself what creates antibacterial properties. It is due to the mechanical process that occurs when washing your hands or body with soap when bacteria is removed and not due to soap’s ingredients. The removal of germs and dirt occurs when soap molecules break down skin’s natural oils in which dirt is trapped; those small particles are then washed away with water.

In addition, despite some controversy around antibacterial additives, such as triscolan, and their effects on bacterial resistance to antibiotics 2 studies showed that adding antibacterial agents to the composition of soap, can remove higher concentrations of bacteria than plain soap 3.

Can bacteria and viruses be passed on via the soap bar?

activated charcoal soap with foam

E. A. Bannan, M.S. and L. F. Judge, Ph.D. 4 studied the ability of soap bar transmitting bacteria such as Staphylococcus aureus (MRSA), a bacterium that can often resist antibiotics and that used to be found solely in hospitals but is now found in schools, jails, and even sport teams, as well as Escherichia Coli bacteria. Their research confirmed that this type of bacteria cannot be transmitted from person to person through a bar of soap, and that bar of soap does not support the growth of such bacteria on its surface.

Although most studies are based on bacteria, there is some research suggesting that bar of soap can also remove viruses from hands, including Ebola 5.

In the recent article from The New York Times called "Why Soap Works?", scientists explain how soap's particles successfully remove viruses, including coronaviruses, during washing with soap. 

Hand washing with soap, is a basic recommendation from health officials to individuals who wish to prevent flu.

How to wash your hands?

washing hands with soap bar

Recent recommendation that you might have heard of is washing your hands for as long as it takes to sing ‘Happy Birthday’ twice - which takes around 30 seconds. Studies shown that washing your hands for 15 seconds reduces bacteria by 90%. Washing your hands for twice that, reduces bacteria by 99.9%. 2

It is recommended that you wash your hands under running water and not standing water, i.e. in a bowl, as it could be contaminated from previous use. Also, contrary to what some might believe, research suggests that water temperature doesn’t seem to have a strong impact on the removal of both resident and transient bacteria from skin. 6

How to keep your soap clean (pun intended!)?

To ensure that your soap bar doesn’t accumulate unwanted bacteria, you should rinse it well after use and keep it dry between uses. Soap dishes such as our Bamboo Soap Dish that allow excess water and slime to drain through can be a good solution for most people.

Also, if you’re using any soap accessories such as our Cotton Soap Bag or loofahs and sponges, you should ensure that they are regularly washed, rinsed, and dried between uses.

What soap to use?

As mentioned above, due to soap's physical composition all our soaps will be antibacterial in nature; some to a higher or lower degree. Below we have selected a few soaps from our large range of soaps available on our website that contain additional antibacterial ingredients. 

Tea Tree & Lemon Soap Bar

Our Tea Tree & Lemon soap bar contains pure tea tree oil that has been proven to have antimicrobial and anti-inflammatory properties. 7

Olive Oil Soap Bar

Olive Oil has been proven to have some antibacterial properties when it comes to uses on skin. 8

Orange & Ylang Ylang

Anti-bacterial properties of Orange Oil help in treating acne. 9

 

 

 

Disclaimer: Please note, the research quoted in this article has been gathered to our best knowledge and recommendations continue to adapt based on best available science. No content on this site should be used as a substitute for medical advice. Please always seek advice from a qualified doctor.

 References: 

1: Revised Estimates for the Number of Human and Bacteria Cells in the Body. Ron Sender, Shai Fuchs, Ron Milo.

2: Harvard Health Letter: The handiwork of good health, 2007. 

3: Antibacterial activity of soaps against daily encountered bacteria. Riaz, Saba; Ahmad, Adeel; Hasnain, Shahida, 2009. 

4: Bacteriological Studies Relating to Handwashing. THE INABILITY OF SOAP BARS TO TRANSMIT BACTERIA. E. A. Bannan, M.S. and L. F. Judge, Ph.D. 1965

5: Handwashing and Ebola virus disease outbreaks: A randomized comparison of soap, hand sanitizer, and 0.05% chlorine solutions on the inactivation and removal of model organisms Phi6 and E. coli from hands and persistence in rinse water. Marlene K. Wolfe, Karin Gallandat, Kyle Daniels, Anne Marie Desmarais, Pamela Scheinman, and Daniele Lantagne. 2017.

6: Water temperature as a factor in handwashing efficacy. Barry Michaels, Vidhya Gangar, Ann Schultz, Maria Arenas, Michael Curiale, Troy Ayers, Daryl Paulson. 2002.

7: Melaleuca alternifolia (Tea Tree) Oil: a Review of Antimicrobial and Other Medicinal Properties. C. F. Carson, K. A. Hammer, and T. V. Riley. 2006

8: Novel antibacterial and emollient effects of coconut and virgin olive oils in adult atopic dermatitis. Verallo-Rowell VM, Dillague KM, Syah-Tjundawan BS. 2008

9: Commercial Essential Oils as Potential Antimicrobials to Treat Skin Diseases. Ané Orchard and Sandy van Vuuren. 2017.