1-Butanol is readily absorbed through the skin, respiratory and gastrointestinal tracts (WHO, 1987; DiVincenzo and Hamilton, 1979; Rumyantsev et al., 1975). Ästrand et al. (1976) found 37-48% efficiency in absorbing alcohol vapor when 12 subjects inhaled 100 or 200 ppm with or without exercise. Arterial blood concentrations were only 0.3 and 0.5 mg/kg (3 and 5 mg/dL) after 30 minutes of exposure at 100 or 200 ppm, respectively. These concentrations doubled after subjects had an additional 30 minutes of exposure at 50 watts (mild physical activity). Accompanying venous concentrations of 1-butanol were approximately half of those reported in arterial blood. In dogs exposed to 50 ppm 1-butanol for 6 hours, respiratory uptake averaged 55%, and 22 ppm 1-butanol was consistently found in exhaled air (DiVincenzo and Hamilton, 1979). Notably, in both experiments, 1-butanol was not detectable in human or dog blood after exposure to 50 ppm. In rats exposed to 500 or 2000 ppm for 6 hours, 1-buta-
National Academies of Sciences, Engineering and Medicine. 1996. Maximum Permissible Concentrations of Selected Air Pollutants from Spacecraft: Volume 3. Washington, DC: National Academy Press.
According to the abstract, all studied butanols, including 1-butanol, distribute freely in the body according to the water content of the tissues (Bechtel and Cornish, 1975). In several animal models, 1-butanol is rapidly removed from the blood and distributed into tissue compartments. After oral administration of 2 g/kg of 1-butanol to rats, the plasma concentration reached 19 mg% within 15 minutes, peaked at 51 mg% after 2 hours, and decreased to 18 mg% after 4 hours (Gaillard and Derache, 1965 ).
National Academies of Sciences, Engineering and Medicine. 1996. Maximum Permissible Concentrations of Selected Air Pollutants from Spacecraft: Volume 3. Washington, DC: National Academy Press.
