Incapacitation in the Laboratory Rat Induced by Inhalation of Carbon Monoxide-Acrolein Mixtures

Laboratory rats were exposed to experimental atmospheres of (a) carbon monoxide (CO), (b) acrolein, and (c) to mixtures of carbon monoxide and acrolein. The toxic potency of each environment was evaluated by measure ment of time-to-incapacitation (t,) as a function of toxic gas concentrations. Regression equations were derived relating observed t,'s to concentrations of in dividual gases. Comparison of individual gas exposure data with results obtained from com bined gas exposures indicated no evidence of synergistic action. Evidence did exist for an inhibitory effect of undefined mechanism when acrolein (in the mix ture) was at a concentration of lesser potency than the CO. An empirical equation was derived that allowed calculation of a predicted t, for exposure to CO-acrolein mixtures at concentrations within the experimen tal exposure ranges.