A laboratory evaluation of commercially available local exhaust ventilation systems marketed to nail salons

Background and Objective: Healthy nail salon programs that promote the voluntary use of alternative cosmetic products and the implementation of safe work practices, including use of local exhaust ventilation (LEV), are increasing in popularity as a way to improve the health of this occupational cohort.  Many LEV systems are marketed to the nail salon industry, but few studies have shown the effectiveness of these systems in reducing chemical exposures.  This study aims to evaluate different types of LEV systems in a controlled environment to better inform recommendations made during healthy nail salon initiatives. Methods: Series of five simulated manicures were performed in a controlled environmental chamber under conditions of no LEV, a high-power LEV, and a lower power tabletop LEV. Time-weighted average airborne concentrations of total volatile organic compounds (TVOC), ethyl methacrylate and formaldehyde were sampled in proximity of the breathing-zone of a worker or customer.  Real-time sampling of TVOC was also performed. Results: Eight-hour time-weighted average concentrations for the no LEV system were 8.1 ppm for TVOC, 1.6 ppm for ethyl methacrylate and 0.009 ppm for formaldehyde.  Real-time TVOC concentrations were reduced by 10 percent when employing high-power LEV but increased by 5.5 percent when using the tabletop LEV system. Conclusion: Despite controlled laboratory conditions, measurements of airborne chemical concentrations vary considerably across manicures, and detailed task analysis is recommended for future field exposure measurements.  Although LEV systems are a recommended safe work-practice, only marginal improvements are observed from their use. Further evaluation of cost-to-benefit ratios is recommended.