Time dependence of blood concentrations during and after exposure to a mixture of volatile organic compounds.

Volatile organic compounds constitute a group of important environmental pollutants that have been associated with the constellation of symptoms known as sick building syndrome. An understanding of the kinetics of uptake and elimination of volatile organic compounds is important for the proper interpretation of the internal dose concentrations of people exposed to these compounds. Blood concentrations measured before, during, and after exposure of five individuals to a mixture of volatile organic compounds in a controlled chamber are described. Blood concentrations were related directly to air exposure concentrations and appeared to be a function of the blood/air partition coefficient. The half-lives of the internal dose of the volatile organic compounds measured were less than 1/2 h, but the elimination time courses were multiexponential. The complexity of the elimination curve suggested the existence of multiple storage sites within the body. The presence of a long-term exponential in the blood elimination curve suggested that, with repeated exposure, bioaccumulation may occur in humans.