What You Can’t See In Your Hand Soap

Liquid soap dispensers are used by millions daily, but as you reach for the soap dispenser to clean your hands you may want to look at the dispenser itself before pumping. All soap dispensers are not alike, and some can potentially harbor more bacteria than they remove!

Prevention Basics
Washing your hands with soap and water is universally considered one of the simplest steps you can take to avoid getting sick and spreading germs. This is especially important as flu season returns and COVID-19 rates continue to climb. But is the familiar wall mounted soap dispenser in the restroom or common area doing more harm than good? That may depend on what type of dispenser it is and how well it’s being maintained.

It’s What’s Inside That Counts
There are two common wall mounted soap dispensers: closed and open bulk-refillable systems. Closed liquid soap dispensers can be refilled with a sealed disposable bag or cartridge. Open bulk-refillable dispensers require soap to be poured into the dispenser from bulk stock soaps that may be concentrated, requiring tap water to dilute the soap.

Bulk-refillable soap dispensers are commonly found in public restrooms in many community settings. Recent studies have shown one in four bulk-refillable soap dispensers are contaminated.1 While soap does not have to be sterile for effective hand washing, the number of bacteria in the soap needs to be minimal and free of harmful organisms. It should also contain enough preservative to prevent contamination of the soap.2

A study conducted in Japan examined contaminated soap dispensers and found 17 different species of bacteria, including Klebsiella pneumoniae, Serratia Marcescens, and Enterobacter, and Pseudomonas.1 Various outbreaks have occurred from contaminated soap resulting in a variety of infections such as bacteremia, joint infections, skin ulcers, and urinary tract infections.2

As new soap is poured into the dispenser, contaminants such as dirt and bacteria can also be introduced during the refill process. Researchers also theorize that preservatives in bulk soap may deteriorate over time which can also lead to contaminated soap.2

Ideally, a refillable dispenser should be cleaned before filling. Wall-mounted dispensers may not have a removable soap container, so cleaning the container that houses the soap can be challenging and the effectiveness of cleaning short-lived. Studies show that even after cleaning a contaminated dispenser with a 10-minute soak of sodium hypochlorite (bleach) solution, the contamination levels return to pre-cleaning levels within 7-14 days.4

The Centers for Disease Control (CDC) discourages the practice of “topping off” or adding new soap to existing soap in the container due to the risk of contamination citing contaminates can enter the dispenser when the top is removed and new soap is added.3

How DermaRite Can Help You
DermaRite’s closed cartridge and bag systems are an easy solution to prevent liquid soap contamination. The disposable closed cartridge or bag provides clean, uncontaminated soap and a new nozzle for delivery of soap with every dispenser refill. A clean, mess-free system will enhance handwashing compliance.

DermaRite offers a variety of liquid hand soaps, hand sanitizers, and skin cleansers for use in a closed system refillable dispenser.

Our line of liquid hand soaps and total body cleansers include:

DermaKleen™: a pH balanced, Triclosan-free antiseptic hand cleanser enriched with vitamin E to soften and condition frequently washed hands. Contains chloroxylenol.
KleenFoam: a pH balanced antiseptic foam hand soap that moisturizes with Aloe Vera for clean, soft, conditioned hands. Contains chloroxylenol.
TotalFoam: a pH-balanced total body wash and shampoo enriched with Aloe Vera which offers a thick rich lather to leave skin soft and fresh.
TotalBath: a mild, pH balanced full body cleanser and shampoo enriched with vitamin E to moisturize and nourish skin.
DermaRain: a pH balanced, dye-free cleanser for sensitive skin that cleans and moisturizes without irritation.
DermaVera: a pH balanced cleanser enriched with shea butter to provide a rich lather with a fresh scent. Nourishes and moisturizes as it cleans.


  1. Zapka, Carrie & Campbell, Esther & Maxwell, Sheri & Gerba, Charles & Dolan, Michael & Arbogast, James. (2011). Bacterial Hand Contamination and Transfer after Use of Contaminated Bulk-Soap-Refillable Dispensers. Applied and environmental microbiology. 77. 2898-904. 10.1128/AEM.02632-10.
  2. The Free Library. S.v. Occurrence of heterotrophic and coliform bacteria in liquid hand soaps from bulk refillable dispensers in public facilities..” Retrieved Dec 01 2020 from https://www.thefreelibrary.com/Occurrence+of+heterotrophic+and+coliform+bacteria+in+liquid+ha nd…-a0249684607
  3. https://www.cdc.gov/mmwr/PDF/rr/rr5116.pdf
  4. Lorenz LA, Ramsay BD, Goeres DM, Fields MW, Zapka CA, Macinga DR. Evaluation and remediation of bulk soap dispensers for biofilm. Biofouling. 2012;28(1):99-109. doi: 10.1080/08927014.2011.653637. PMID: 22257312.

Deeper Dive

Want to learn more about this topic? In addition to the reference links above, here are some great articles and resources that you can explore.

  1. https://oshareview.com/2016/10/hand-hygiene-do-not-top-off-soap-dispensers-infection-control/
  2. https://professionals.wrha.mb.ca/old/extranet/ipc/files/manuals/acutecare/Topping_up_and_Reusing.pdf
Posted in Clinical Insights Newsletter
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