title: Evaluation and remediation of bulk soap dispensers for biofilm.
abstract: Recent studies evaluating bulk soap in public restroom soap dispensers have demonstrated up to 25% of open refillable bulk-soap dispensers were contaminated with ~ 6 log(10)(CFU ml(-1)) heterotrophic bacteria. In this study, plastic counter-mounted, plastic wall-mounted and stainless steel wall-mounted dispensers were analyzed for suspended and biofilm bacteria using total cell and viable plate counts. Independent of dispenser type or construction material, the bulk soap was contaminated with 4-7 log(10)(CFU ml(-1)) bacteria, while 4-6 log(10)(CFU cm(-2)) biofilm bacteria were isolated from the inside surfaces of the dispensers (n = 6). Dispenser remediation studies, including a 10 min soak with 5000 mg l(-1) sodium hypochlorite, were then conducted to determine the efficacy of cleaning and disinfectant procedures against established biofilms. The testing showed that contamination of the bulk soap returned to pre-test levels within 7-14 days. These results demonstrate biofilm is present in contaminated bulk-soap dispensers and remediation studies to clean and sanitize the dispensers are temporary.
authors.affiliation: Center for Biofilm Engineering, Montana State University, Bozeman, Montana 59717, USA.
authors.forename: Lindsey A
authors.initials: LA
authors.lastname: Lorenz
authors.forename: Bradley D
authors.initials: BD
authors.lastname: Ramsay
authors.forename: Darla M
authors.initials: DM
authors.lastname: Goeres
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Fields
authors.forename: Carrie A
authors.initials: CA
authors.lastname: Zapka
authors.forename: David R
authors.initials: DR
authors.lastname: Macinga
mesh_terms: D001419:Bacteria / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification*; D058491:Bacterial Load; D018441:Biofilms / Q000187:drug effects*; D004202:Disinfectants / Q000494:pharmacology; D004203:Disinfection / Q000379:methods; D004783:Environmental Microbiology; D052918:Environmental Restoration and Remediation / Q000379:methods*; D004866:Equipment Contamination / Q000517:prevention & control; D050456:Fomites / Q000382:microbiology*; D006225:Hand; D006235:Hand Disinfection / Q000379:methods; D006801:Humans; D010969:Plastics / Q000032:analysis; D011633:Public Facilities; D012915:Soaps / Q000032:analysis*; D012973:Sodium Hypochlorite / Q000494:pharmacology; D013193:Stainless Steel / Q000032:analysis; D013997:Time Factors
chemical_list: D004202:Disinfectants; D010969:Plastics; D012915:Soaps; D013193:Stainless Steel; D012973:Sodium Hypochlorite