Decreased activity of commercially available disinfectants containing quaternary ammonium compounds when exposed to cotton towels

Abstract

Background: Health care-associated infections (HAIs) are a significant problem in hospitals, and environmental surfaces have been implicated as a source of HAIs in the hospital environment. Furthermore, Gram-negative and Gram-positive bacteria can persist on dry environmental surfaces for as long as several months. Poorly cleaned surfaces may serve as vehicles for microbes, which may then be transferred to patients.

Methods: Cotton and microfiber towels were both tested for their abilities to bind quaternary ammonium compounds (QACs). The towels were exposed to 3 commercially available disinfectants for 0.5, 30, and 180 minutes. Germicidal spray tests (GSTs) were performed for all towel eluates in accordance with the AOAC International method 961.02. Cotton towel eluates were analyzed for QAC concentration using high-performance liquid chromatography.

Results: QAC concentrations were reduced by up to 85.3% after exposure to cotton towels, resulting in failure of the disinfectants exposed to cotton towels in 96% of the GSTs.

Conclusion: The use of cotton towels with QAC-based cleansers should be reconsidered, particularly in hospitals where effective cleaning of the patient environment is needed to reduce the risk of HAIs.

Keywords: Disinfection; HAI; Hospital surfaces; Inactivation; Microfiber.