Inhalation Toxicity of Peroxyacetyl Nitrate

Depression of voluntary wheel-running activity was determined in young adult C57BL male mice which inhaled the photochemical air pollutant peroxyacetyl nitrate (PAN) for a six-hour period at one of five concentrations. All five levels significantly depressed both six-hour (exposure period) and 24-hour activity when compared to the immediately previous similar period. Depression occurred more rapidly and was more complete the higher the exposure level. The six-hour activity50 concentration was 4.5 ppm. The toxic potency of PAN ranked with that of other pollutants in descending order as follows: ozone, acrolein, nitroolefins, ozonized gasoline vapor, PAN nitrogen dioxide, carbon monoxide, and irradiated and nonirradiated auto exhaust.