Body burden profiles of single and mixed exposure to solvents.
Brown-WD; Setzer-J; Dick-RB; Phipps-FC; Lowry-LK
NIOSH 1986; :111-114
Blood and breath concentrations from controlled exposures to acetone (67641) and methylethyl-ketone (78933) (MEK) vapors were studied in humans. The study was part of a larger study of the neurobehavioral effects of acetone and MEK. Seventy healthy male and female volunteers, 18 to 32 years old, with no previous prolonged exposure to solvents were exposed to 0 or 250 parts per million (ppm) acetone, 200ppm MEK, or 125ppm acetone plus 100ppm MEK vapors for 4 hours in an exposure chamber. Expired air samples were collected before exposure, after 2 and 4 hours' exposure, 90 minutes after exposure ended, and the next morning. Blood samples were collected on the day preceding exposure, at 2 or 4 hours of exposure, 2 hours after exposure ended, and the following day. Samples were analyzed for acetone and MEK by gas or gas/liquid chromatography. Acetone was detected in breath and blood of the subjects prior to exposure. Blood MEK or acetone concentrations continued to increase throughout exposure, the increases between 2 and 4 hours being larger in the case of acetone. Acetone concentrations in the breath took longer to decrease than those of MEK. No interactive effects were noted in the combined exposures. Blood acetone and MEK concentrations were moderately correlated with their breath concentrations. Blood MEK and acetone concentrations tended to be lower in female subjects than in males; however, the differences were significant only for acetone in the combination exposure after 2 hours' exposure and 90 minutes' postexposure. The biological halflives for elimination of acetone and MEK calculated on the basis of a first order kinetic assumption were 3.9 hours and 49 minutes, respectively. The authors conclude that workers exposed to acetone or MEK for 6 to 8 hours could expect to have a residual body burden of acetone the next morning, whereas MEK would be essentially eliminated.
NIOSH-Author; Organic-solvents; Ketones; Body-burden; Blood-samples; Chemical-analysis; Exposure-chambers; Laboratory-testing; In-vivo-studies; Kinetics
The Changing Nature of Work and Workforce, Proceedings of the Third Joint US-Finnish Science Symposium, Frankfort, Kentucky, October 22-24, 1986, NIOSH, Cincinnati, Ohio