Inhalation kinetics of C8 to C10 1-alkenes and iso-alkanes in the rat after repeated exposures.

The toxicokinetic properties of C8 and C10 1-alkenes and iso-alkanes have been investigated in rats during inhalation of 100 p.p.m. of the single hydrocarbons for 3 days, 12 hr/day. The concentration of hydrocarbon was measured in blood, brain, liver, kidneys and perirenal fat at days 1, 2 and 3, immediately after exposure and 12 hr after exposure on day 3. The 1-alkenes showed an efficient absorption to blood combined with extensive accumulation in organs, compared to the iso-alkanes. The concentration of 1-alkenes and iso-alkanes in blood, brain, liver and fat increased with increasing number of carbon atoms. The C9 and C10 1-alkenes and iso-alkanes showed increasing concentration in fat during the exposure period and high concentrations 12 hr after cessation of exposure. The extensive accumulation in both blood and organs of 1-alkenes compared to any of the other groups of hydrocarbons may have a toxicologic relevance. Products which contain 1-alkenes should be handled carefully to minimize the risk of inhalation exposure.