Volatilization of chemicals from tap water to indoor air from contaminatedwater used for showering

Volatile organic compounds (VOCs) may enter indoor air during the use of co ntaminated tap water. When this occurs, occupants can become exposed to pot entially toxic VOCs via the inhalation route. The propensity for VOCs to vo latilize into indoor air during the routine use of showers was investigated . A series of mass transfer experiments were conducted while a shower was o perated within an enclosed chamber. Acetone, ethyl acetate, toluene, ethylb enzene, and cyclohexane were used as volatile tracers. Chemical-specific st ripping efficiencies and mass transfer coefficients were determined. An ass essment of the importance of gas-phase resistance to mass transfer from wat er to air was also completed. Chemical-specific stripping efficiencies rang ed from 6.3% (for acetone) to 80% (for cyclohexane) for household showers u sed under normal conditions. As described in this paper, data resulting fro m this study allow for the determination of overall mass transfer coefficie nts, and corresponding volatilization rates, for any showering event and ch emical of interest. As such, the information presented herein should lead t o improved estimates of human inhalation exposure to toxic chemicals that v olatilize from water to indoor air.