INTRODUCTION GASOLINES are exceedingly complex mixtures of aromatic hydrocarbons@ alkanes@ cycloalkanes@ and olefins boiling in a range of 80-345?? The exact composition of gasolines varies depending on the crude oil source@ the refining conditions@ and so on. Organometallic compounds are added in relatively small amounts in order to produce desired handling@ storage@ and combustion properties. The literature is relatively sparse with respect to gasoline toxicity studies. The earliest animal study@ by Haggard (1921)@ defined the acute anesthetic and toxic effects of gasoline vapors in dogs. Central nervous system effects were observed at about 10@000 ppm@ and death was observed at about 25@000 ppm. Lykke and Steward (1978) exposed rats for 6-12 weeks to 100 ppm of a commercial 98 octane leaded gasoline. They found progressive focal interstitial fibrosis of the lung that was associated with irregular alveolar collapse. Gasoline vapor exposures in humans were investigated by Drinker et al. (1943)@ who observed signs of eye irritation at 700 ppm and slight anesthesia at 2600 ppm. Much of oru knowledge regarding the toxicity of gasoline derives from cases involving gasoline sniffers who deliberately inhale gasoline at exposures well in excess of those noted above. Clinical observations include signs of central and peripheral nervous system abnormalities@ muscle atrophy@ and hepatic and renal damage (Robinson@ 1978). Irreversible encephalopathy has been attributed to added organic lead and not to the gasoline hydrocarbon itself (Valpey et al.@ 1978).