Respiratory exposure and potential dermal exposure to volatile organic compounds in nail salons : a pilot study / C. Spoelstra

Abstract

Objectives: The aims of this pilot study were to quantify respiratory and potential dermal exposure of nail technicians to acetone, formaldehyde, ethyl methacrylate, methyl methacrylate, toluene and xylene. Fifteen female nail technicians, working in different salons participated in this study. Products used for nail treatments differed between salons. Most salons used acrylate based nail products whereas others used UV–gel products exclusively. Methods: The participants were divided into two groups, those who used acrylate– and those who used UV–gel products exclusively. Eight hour personal respiration exposure to acetone, formaldehyde, ethyl methacrylate, methyl methacrylate, toluene and xylene were determined. The concentration of airborne volatile organic compounds in the salons was also determined with the use of a direct reading instrument (EntryRAE). Potential dermal exposure to the above mentioned solvents (excluding formaldehyde) was determined with the use of charcoal pads (surrogate skin method). During respiratory and dermal sampling, observations were made regarding work practices and control measures used in the salons. Results: It was found that the eight hour time weighed average exposure is well below the recommended occupational exposure limits of the individual chemicals and showed no additive effect. The highest mean respiratory exposures in both groups were acetone (27.22 mg/m3 and 28.36 mg/m3). EntryRAE results showed peak periods of exposure to volatile organic compounds during the day (322.16 ppm) that were much higher than the average eight hour exposure (0.21 ppm). The two groups’ exposure levels were compared to determine if there is a significant difference between the exposures levels but no statistically significant difference was found. The dermal exposures on hand and neck to acetone, ethyl methacrylate and methyl methacrylate showed strong significant correlations to the concordant chemical’s respiratory exposures. Correlations between air and dermal exposure was calculated once more after adjusting dermal exposure but the findings indicated only one statistically significant correlation of 0.42 in the case of ethyl methacrylate. Conclusion: Nail technicians are not at immediate health risk as the exposure in nail salons are well below recommended occupational exposure limits. However the unknown effects of chronic low level exposure to solvents and the large number of previous studies that reported increased health risks in nail technicians must also be considered. The use of methyl methacrylate in nail products sold in South Africa is also worrying as methyl methacrylate is banned by the FDA in the US due to its skin sensitisation potential that may lead to allergic contact dermatitis. The methods used to determine potential dermal exposure as well as adjusted dermal exposure remains problematic. This is due to the high percentage of adjusted dermal exposure values that had to be estimated and the fact that the activated charcoal pads have a higher absorption potential than human skin. Both methods must be improved to increase accuracy of results. Observations and EntryRAE results demonstrated the irregular nature of a nail technician’s work shift as well tasks performed from day to day. This complicates gathering data that is representative of a nail technicians eight hour exposure. Therefore to further improve accuracy of results, sampling should in future be task specific.