Occupational Exposures to New Drycleaning Solvents: High-flashpoint Hydrocarbon or Butylal

Background: The drycleaning industry is moving away from using perchloroethylene. Although new drycleaning solvents like high-flashpoint hydrocarbons and butylal are gaining prominence, occupational exposures have not been well-characterized.

Objective: Characterize occupational exposures to high-flashpoint hydrocarbon and butylal and identify controls to reduce exposures.

Methods: We collected air samples in two shops that used butylal. Because there are no occupational exposure limits (OELs) for butylal we also assessed the health risks using control banding tools. We collected personal and area air samples for butylal as well as for formaldehyde and butanol, potential byproducts from the hydrolysis of butylal. We also collected air samples in two shops that used a high-flashpoint hydrocarbon as a drycleaning solvent.

Results: The highest airborne exposures occurred when employees loaded and unloaded the drycleaning machines and pressed fabrics. Airborne exposures to formaldehyde and butanol were well below OELs. Airborne exposures to the high-flashpoint hydrocarbon were also well below OELs.  However, we observed skin exposures to these solvents.

Conclusions: We recommended changes to  work practices and proper selection and use of personal protective equipment to further minimize occupational exposures. These recommendations were consistent with those derived using our control banding tools for butylal. However, there is insufficient toxicological and health information to determine the safety of these solvents in occupational settings. Independent toxicological evaluation of these new drycleaning solvents is urgently needed before they can be unreservedly recommended as safer alternatives to perchloroethylene.