Mice were examined for effects on lethality and motor performance on an inverted screen test following inhalation exposure to isoamyl, n-butyl and isobutyl nitrite. All three nitrites produced concentration-related effects on both measures, with EC50s for motor performance only about one-half of the LC50s for lethality. Isoamyl and isobutyl nitrite were equally potent on both lethality and motor performance measures, whereas n-butyl nitrite was significantly more potent than isoamyl and isobutyl for lethality. Slope estimates of the concentration-effect curves for lethality were significantly greater than those of the motor performance measure. The steepness of the concentration-effect curves and low LC50/EC50 ratios relative to abused organic solvents suggest that behaviorally active concentrations of volatile nitrites may put users at risk to other health consequences.
