A comparison of the absorption and metabolism of isopropyl alcohol by oral, dermal and inhalation routes.

The admission of a child with an almost lethal level of isopropyl (alcohol 380 mg/dl) after sponge bathing for fever, and questionable ingestion, prompted the present experiment in animals. Twelve rabbits (2-2.6 kg) were divided into 4 groups of 3 each. Groups 1 and 2 were given isopropyl alcohol, 2 and 4 ml/kg respectively, by gavage. Groups 3 and 4 were placed in an inhalation chamber with group 3 having a towel soaked with isopropyl alcohol applied to the chest. Group 4 had a similar towel placed on the chest but with a plastic layer to preclude skin contact. Average blood levels (mg/dl) of isopropanol/acetone were then measured over 4 hr. Oral absorption produced the highest levels of isopropyl alcohol and acetone, followed by inhalation and dermal. Inhalation alone was of little significance. Acetone levels continued to rise even as isopropyl levels fell following oral exposure. With the inhalation plus skin absorption group, both isopropyl and acetone levels continued to rise throughout the 4 hr time period. These results indicate that skin absorption is a significant factor in isopropyl alcohol toxicity, and the delayed rise in acetone levels may be responsible for prolonged activity.