Presence of unsafe chemical impurities, accelerated evaporation of alcohol, and lack of key labeling requirements are risks and concerns for some alcohol-based hand sanitizers and dispenser practices during the COVID-19 pandemic

Abstract

Alcohol-based hand sanitizers (ABHS) have been an important hand hygiene tool during the COVID-19 pandemic. Recently, ABHS from non-traditional drug manufacturers have entered the market, triggered by a lack of ABHS availability. Some of these ABHS contain high levels of chemical impurities that may be harmful with frequent exposure. Additionally, the use of refillable dispensers designed to accept ABHS from bulk containers allows for mixing and evaporation that may compromise ABHS integrity. To understand the risks associated with low quality ABHS and bulk refilling practices, we collected 77 ABHS samples sourced from community settings (restaurants, grocery stores, etc.) and 40 samples from a single school district. All samples were obtained from bulk refillable dispensers that were in use. Samples were analyzed for alcohol content, chemical impurities, aesthetic qualities, and presence of drug labeling information. Additionally, we performed laboratory-based experiments to determine the impact of dispenser design on alcohol evaporation rates. Over 70% of samples for which photos were available showed lack of essential labeling information, including missing "Drug Facts Labels". For ABHS samples acquired from community settings, nearly 14% of samples had visible impurities, and over 30% of samples had concentrations of acetal and acetaldehyde in excess of FDA interim limits. Subpotent ethanol concentrations were observed in 9.09% and 82.05% of samples from community settings and the school district, respectively, with the school district sample results being associated with dispenser misuse. Laboratory-based experiments show dispenser design significantly impacts the rate of ethanol evaporation of ABHS products, especially if stored in open refillable dispensers without an internal reservoir. This study demonstrates risks associated with use of inferior ABHS and bulk refilling practices. Regulatory agencies should issue guidance on best practices in community settings to ensure the integrity of ABHS as an essential public health tool to prevent the spread of COVID-19 and other transmissible diseases.

Fig 1. Flow chart of experimental design.

Panel A: Field sampling of ABHS from bulk refillable dispensers. Panel B: Evaluation of rate of ethanol evaporation of dispenser and ABHS under accelerated stability conditions.

Fig 2. Ethanol concentration in ABHS samples sourced from single school district.

Ethanol concentration of ABHS samples from single school district in South Carolina. Panel A: Distribution of ethanol concentrations (% v/v) measured from 39 individual dispensers. Black dashed line indicates 60% ethanol, the minimum concentration of ethanol required for the ABHS product to be compliant with FDA OTC Drug regulations [23]. Panel B: Average ethanol concentration is associated with status of refill cap placement. A total of 39 ABHS samples from a single school district was analyzed for ethanol concentration. Upon inspection of photos, many dispensers had refill caps removed (n = 19), some had caps installed (n = 7), and some were unable to determine based on photographs (n = 13). When grouped by status of cap placement, a significant difference in average ethanol concentrations (% v/v) was observed. Refill cap status (with or without) was significantly associated with rate of ethanol loss (P < .05) based on one-way ANOVA with cap status as treatment and average ethanol concentration as independent variable. Letters above each bar graph indicate statistically different mean ethanol percentages using Tukey’s HSD post-hoc test for separation of means.

Fig 3. Observed ethanol loss in ABHS stored in bulk refillable dispensers (pooled across all ABHS types) under accelerated stability conditions (40 ± 2°C, RH of 75 ± 5%).

Rate of monthly ethanol loss of ABHS stored in various bulk refillable dispensers held in accelerated stability conditions. For both panels, ethanol content is pooled across all ABHS types (e.g., foam, gel, liquid/WHO), since ABHS type was not found to significantly impact the rate of ethanol evaporation (data shown in S1 Fig; P > 0.05). Controls were two sanitary sealed 1200mL refill bottles of ABHS products from GOJO Inc. (details in Materials and Methods). Panel A: Observed ethanol loss over 6 months of storage time for ABHS stored in bulk refillable dispensers. Samples were stored at 40 ± 2°C, RH of 75 ± 5%, and aliquots for analysis were measured after 0, 1, 2, 3, and 6 months of storage. Bolded shapes on the graph represent mean ethanol percent (v/v) values for duplicate aliquots at each indicated time point. Dashed lines represent a linear fit trendline based on all data points. Dispenser types appear on the legend, and details of each dispenser type appear in S1 File in the supplemental materials. Panel B: Monthly loss of ethanol represented as the inverse slope of a linear trendline of ethanol content as a function of time when dispenser × ABHS combinations were stored for 6 months at accelerated conditions (from Panel A). Error bars represent standard error of the mean. Dispenser type was significantly associated with rate of ethanol loss (P < .05) based on one-way ANOVA with dispenser type as treatment and average monthly ethanol loss as independent variable. Letters above each bar graph indicate statistically different mean ethanol percentages using Tukey’s HSD post-hoc test for separation of means.