REPORT: Alcohol Gel Safety and Efficacy

May 6, 2003

There are many brands of alcohol-based sanitizing gels available on the market. They contain 62% to 68% ethanol or isopropanol.

Quite a few doctors and nurses who have abandoned the ritual of washing their hands with soap and water between patients and instead rub on fast-drying alcohol gels to kill germs; however, the safety and efficacy of alcohol gels are subject to controversy. There are several reports, which indicate that alcohol-based liquid gels are not always safe or effective as an anti-microbial hand sanitizer.

Safety:
Even well tolerated alcohol hand sanitizers, which contain emollients, may cause a transient stinging sensation at the site of any broken skin (e.g., cuts and abrasions). Alcohol-based, hand-rub preparations may also be poorly tolerated by healthcare workers with respiratory allergies. Allergic contact dermatitis or contact urticaria syndrome caused by hypersensitivity to alcohol or to various additives present in certain alcohol hand rubs do occur (1,2).

Alcohols are flammable. Flash points of alcohol-based hand rubs range from 21¬∫C to 24¬∫C, depending on the type and concentration of alcohol present (3). As a result, alcohol-based hand rubs need to be stored in cool temperatures in accordance with National Fire Protection Agency recommendations. In Europe, where alcohol-based hand rubs have been used extensively for years, the incidence of fires associated with such products has been witnessed (3,4).  These incidents emphasize the need to rub hands together after application of alcohol-based products until all the alcohol has evaporated. However without alcohol, there is no anti-Microbial activity. Contamination of alcohol-based solutions has been reported. One report documented a cluster of pseudoinfections caused by contamination of ethyl alcohol by Bacillus cereus spores (5).

Skin that is damaged by repeated exposure to hand washing is more susceptible to irritation by alcohol-based preparations (6). The irritancy potential of commercially prepared hand-hygiene products, which is often determined by measuring transepidermal water loss, may be available from the manufacturer. Other factors that can contribute to dermatitis associated with frequent hand washing include low relative humidity (most common in winter months), failure to use supplementary hand lotion or cream, and the quality of paper towels (7,8). Shear forces associated with wearing or removing gloves and allergy to latex proteins may also contribute to dermatitis of the hands of healthcare workers. Well-formulated anti-microbial moisturizers with use of Triclosan not only offer the highest protection against microorganisms, they add hydration to the skin and are preventive in dry skin conditions. LSC Anti-Microbial Moisturizer also incorporates its patented Hydroxysomes‚Ñ¢ Technology whereby the anti-oxidants in its formulations are designed to protect the integrity of the skin and maintain it in a healthy condition with moisture-retention properties.

Efficacy:
The alcohol gels typically provide instant protection but offer no long-term persistence. In addition, the efficacy of alcohol-based hand-hygiene products is affected by several factors, including the type of alcohol used, concentration and volume of alcohol, contact time, and whether the hands are wet when the alcohol is applied. Applying small volumes (i.e., 0.2--0.5 ml) of alcohol to the hands is not more effective than washing hands with plain soap and water (9,10). One study documented that 1 ml of alcohol was substantially less effective than 3 ml (11). The ideal volume of product to apply to the hands is not known and may vary for different formulations. However, after rubbing hands together for 10--15 seconds, an insufficient volume of product is likely available. Furthermore, because alcohol-impregnated towelettes contain a limited amount of alcohol, their effectiveness is comparable to that of soap and water (9,12,13).

Prepared by: Umeji Murakami, Ph. D., Director of R&D; Laboratory Skin Care®, Inc.

References:
(1). Ophaswongse S, Maibach HI. Alcohol dermatitis: allergic contact dermatitis and contact urticaria syndrome: a review. Contact Dermatitis 1994;30:1--6.
(2). Rilliet A, Hunziker N, Brun R. Alcohol contact urticaria syndrome (immediate-type hypersensitivity): case report. Dermatologica 1980;161:361--4.
(3). Widmer AF. Replace hand washing with use of a waterless alcohol hand rub? Clin Infect Dis 2000;31:136--43.
(4). Bryant KA, Pearce J, Stover B. Flash fire associated with the use of alcohol-based antiseptic agent [Letter]. Am J Infect Control 2002;30:256--7.
(5). Hsueh PR, Teng LJ, Yang PC, Pan HL, Ho SW, Luh KT. Nosocomial pseudoepidemic caused by Bacillus cereus traced to contaminated ethyl alcohol from a liquor factory. J Clin Microbiol 1999;37:2280--4.
(6). Lübbe J, Ruffieux C, van Melle G, Perrenoud D. Irritancy of the skin disinfectant n-propanol. Contact Dermatitis 2001;45:226--31.
(7) qhlenschlaeger J, Friberg J, Ramsing D, Agner T. Temperature dependency of skin susceptibility to water and detergents. Acta Derm Venereol 1996;76:274--6.
(8). Emilson A, Lindberg M, Forslind B. The temperature effect of in vitro penetration of sodium lauryl sulfate and nickel chloride through human skin. Acta Derm Venereol 1993;73:203--7.
 (9). Marples RR, Towers AG. A laboratory model for the investigation of contact transfer of micro-organisms. J Hyg (Lond) 1979;82:237--48.
(10).  Mackintosh CA, Hoffman PN. An extended model for transfer of micro-organisms via the hands: differences between organisms and the effect of alcohol disinfection. J Hyg (Lond) 1984;92:345--55.
(11). Larson EL, Eke PI, Wilder MP, Laughon BE. Quantity of soap as a variable in handwashing. Infect Control 1987;8:371--5.
(12). Jones MV, Rowe GB, Jackson B, Pritchard NJ. The use of alcoholic paper wipes for routine hand cleasing: results of trials in two hospitals. J Hosp Infect 1986;8:268--74.
(13). Butz AM, Laughon BE, Gullette DL, Larson EL. Alcohol-impregnated wipes as an alternative in hand hygiene. Am J Infect Control 1990;18:70--6.