Cleaning & Maintenance Management Online

GOJO Release

March 9, 2010

AKRON, OH — Approximately 23 percent of the soap from open refillable (bulk soap) dispensers in public restrooms are highly contaminated with bacteria. A recent study confirms that bulk soap dispensers in schools are similarly tainted.

The findings of a study of bulk soap dispensers in a school were recently presented at a meeting of the National Association of School Nurses (NASN) held in Boston. Among other things, the study found that washing with soap from bulk dispensers left ten times as many bacteria on students'' hands as was found on hands washed with soap from sealed refills. The research also suggests that contaminated bulk soap may play a role in the transmission of bacteria in schools, particularly among children.


Bulk dispensers are refilled by pouring soap from a large container into an open reservoir. Typically the nozzle that dispenses the soap is not replaced. In contrast, sealed dispensing systems utilize sealed bags or cartridges that contain soap, along with a new nozzle.

Soap in bulk dispensers is prone to contamination because the soap is constantly exposed to bacteria from the environment, such as from the hands and body of the person refilling the soap, the spray of toilet water after flushing, and even from dust in the air.

In previous studies, soap from more than 500 dispensers across the United States was tested to evaluate the prevalence of contaminated soap in public restrooms.1
"We were surprised to learn that the soap from one in four bulk dispensers is contaminated with an average of more than three million bacteria, many of which are known to be opportunistic pathogens," said Carrie Zapka, microbiology scientist, GOJO Industries. She continued, "Exposure to such high levels of these organisms can be a significant health risk to individuals with compromised immune systems – estimated to be at least 20 percent of the population.2 In contrast, soap from sealed dispensing systems was free from contamination."

In addition to Zapka, others who were involved in helping to conduct the study include Dr. Charles P. Gerba and Sheri L. Maxwell, both from the University of Arizona; and David R. Macinga, microbiology principal scientist, Michael J. Dolan, senior advisor/science and technology vice president, and James W. Arbogast, skin care science and technology director, from GOJO Industries.

Since contaminated bulk soap has caused outbreaks in hospitals, the U.S. Centers for Disease Control (CDC) recommends against the use of "topping off" dispensers in healthcare settings. However, no such guidelines exist to protect students in schools or patrons of public restrooms in the community.

Test Methodology

To determine whether or not bulk soap dispensers in a school setting contain bacteria, 10 staff members and 10 students in an elementary school participated in a hand washing study. The objective of this study was to evaluate bacterial hand contamination and hand transmission among children and adults in an elementary school with a contaminated bulk soap problem.

In a particular elementary school in Ohio, it was determined that the antibacterial soap in all of the school’s dispensers was highly contaminated with 19 different species of bacteria, including Pseudomonas, Providencia, Citrobacter, Stenotrophomonas, Aeromonas, Enterobacter, Pasteurella and Serratia.

Each of the 20 students and staff participated in up to four hand washes each, using one of 14 contaminated bulk soaps. Participants were instructed to wash and dry their hands as they normally would after using the restroom. All hands were tested both before and after handwashing using two different methods: the number of bacteria on one hand of each participant was measured; and the bacterial transfer to a surface was measured with the opposite hand using a technique known as "the hand stamp procedure."

In a follow-up study conducted four months after the contaminated bulk soap dispensers were replaced with sealed soap dispensing systems, 11 staff participated in up to two hand washes each.


The results of the school study demonstrated that washing with contaminated bulk soap increased the number of bacteria on hands, and also increased the number of bacteria transferred from hands to surfaces. Among the findings:

· Washing with contaminated bulk soap significantly increased the number of pathogenic bacteria per hand from 179 to 2047 on average for all students and staff. Students'' hands retained significantly more bacteria than staff members'' hands.

· Washing with contaminated bulk soap significantly increased the number of bacteria transferred to a surface from one before washing to 27 after washing on average for all students and staff. Also, students transferred significantly more bacteria to the surface they touched after washing with contaminated bulk soap than the staff did, specifically 38 vs. 9 bacteria.

· Washing with sealed soap significantly reduced the number of bacteria from 821 to 135.

· Hands washed with contaminated bulk soap transferred a significantly higher number of opportunistic pathogens to touched surfaces compared to hands washed with soap from a sealed refill.

The study also concluded that contaminated bulk soap may play a role in the transmission of bacteria in schools, particularly among children. It was noted that schools using bulk soap dispensers could reduce the spread of bacteria simply by changing to dispensers which utilize only sealed soap refills.

For more information about the study, go to or contact Angela Watkins, GOJO Industries communications and media relations manager, at 330-255-6612.

About GOJO

GOJO Industries, inventors of PURELL® Instant Hand Sanitizer, distributes PURELL in away-from-home markets throughout the world. In addition, GOJO manufactures and distributes a full line of products under the GOJO® and PROVON® brand names. GOJO has a 63-year history of leadership in improving well-being through hand hygiene and healthy skin. GOJO has products and programs to kill germs on hands and solve skin care-related problems in a variety of settings, including healthcare, foodservice, food processing, manufacturing, automotive, education, government and military. GOJO is a privately held corporation headquartered in Akron, Ohio, with offices in the United Kingdom, Japan and Brazil.
PURELL is a trademark of Johnson & Johnson and is used under license.

1Gerba, CP; Maxwell, S. Bacterial Contamination of Liquid Hand Soaps Used in Public Restrooms. The National Environmental Health Association 71st Annual Educational Conference & Exhibition. Atlantic city, NJ; June 18-21, 2007.

2Gerba, CP; Rose, JB; Haas, CN. Sensitive populations; Who is at the greatest risk: International Journal of Food Microbiology. V30. 1996. P113-123.