Predictions of Blood Ethanol Levels Resulting From Occupational Use of Hydro Alcoholic Solutions and Ethanol-Based Varnishes

Abstract

The purpose of this study was to produce data on the ethanol concentrations in ambient air that result from hand rubbings with hydroalcoholic solutions (HAS) or the use of ethanol-based varnishes, and then to predict the blood ethanol levels (BELs) that result from these procedures. The concentration of ethanol in air at the volunteer’s nose after the application of HAS on hands was measured with five volunteers who performed five tests in two different environments: 1) in an inhalation chamber (air change rate ~18 h-1), and 2) in a closed office (poorly ventilated) with two different amounts (1.5 and 3 g) of HAS. In the case of varnish, 125 ml were applied on a 1-m 2 wood surface placed in the middle of an inhalation chamber (n=4). The ethanol concentration was measured 20 cm and 40 cm from the center of the board for the next 60 minutes. As for HAS we noted a large intra- and inter-individual variability in ethanol levels in inhaled air. As expected the highest concentration in the inhalation chamber (~1250 ppm) was lower than in the office (~2352 ppm). For the application of the varnish, the ethanol concentrations greatly exceeded 1000 ppm for a short duration (< 4 min). Physiologically-based pharmacokinetic (PBPK) modeling of ethanol concentrations based on ethanol levels measured in inhaled air predicted the following maximum BELs in women (men): 0.39 and 0.37 mg/L (0.37 and 0.35 mg/L) in the office, and 0.26 and 0.42 mg/L (0.25 and 0.40 mg/L ) in the inhalation chamber for 1.5 g and 3 g, respectively. The total dose of ethanol absorbed estimated for a working day involving 42 hand rubbings with 1.5 or 3 g of HAS averaged 0.20 g. For the varnish, the predicted highest BELs for men and women were 0.77 and 0.79 mg/L, respectively. In all cases, the BELs remained below 1 mg/L. The results of this study should make it easier to assess the risk related to chronic inhalation of low levels of ethanol in the general population and among workers associated with these practices.