Factors influencing tetrachloroethylene concentrations in residences above dry-cleaning establishments.

Indoor air quality has been increasingly recognized as a significant public health problem. Proximity to industrial or commercial sources contributes to contamination in homes. Air sampling was conducted at 12 residences in 8 buildings that housed dry cleaners and 6 residential control sites. The authors found that concentrations of tetrachloroethylene, a dry-cleaning solvent, were elevated significantly in residences located in buildings that also housed dry-cleaning establishments (mean = 2.0 mg/m3) relative to their concentrations in control residences (mean = < 0.07 mg/m3 [p < .001]). Tetrachloroethylene concentrations remained elevated when the cleaners were closed on weekends (p < .01). The authors verified that colorimetric detector tubes were a useful screening tool for residences. Also identified were factors that could affect tetrachloroethylene concentrations. The use of exhaust fans and the implementation of required inspection and maintenance requirements by dry cleaners were associated significantly with reduced tetrachloroethylene concentrations in residences (p < .01). In all cases, tetrachloroethylene concentrations exceeded "minimal risk levels" posited by the Agency for Toxic Substances Disease Registry for chronic exposure to tetrachloroethylene. Residents who live in buildings that house dry cleaners may be exposed at concentrations that are of public health concern. Measures that might reduce this exposure were also identified.