TOXICOLOGICAL EVALUATION OF 1-CHLOROACETOPHENONE AND DIBENZ[B,F]-1,4-OXAZEPINE AFTER REPEATED INHALATION EXPOSURE IN MICE

Toxicological evaluation was made on the effects of two peripheral sen sory irritants (tear gases): 1-chloroacetophenone (CN) and dibenz[b,f] -1,4-oxazepine (CR). Animals had a 15-min daily inhalation exposure to average vapour concentrations of 87.6 mg CN m(-3) or 1008 mg CR m(-3) (both equal to 0.05 LC(50)) for 5 of 10 days and were sacrificed 24 h after the last exposure, when biochemical and histopathological obser vations were made. Both chemicals caused a significant decrease in bod y weight gain. Histological changes in lung, liver and kidneys were mo re severe after 10 than after 5 days of exposure and were more severe in CN-exposed than in CR-exposed mice. Organ weight to body weight rat ios remained normal except for the spleen to body weight ratio, which decreased in CN-exposed mice after both 5 and 10 days of exposure. Bio chemical indicators showed a toxic response only in CN-exposed mice, b ut the only consistent change was an increase in blood glucose. Hepati c alkaline phosphatase was not influenced, malondialdehyde concentrati on and acid phosphatase activity were increased only after 5 days of e xposure and liver GSH concentration decreased after 10 days of exposur e. Results indicate that CN is not only more toxic than CR in absolute terms but is also more toxic at the 5% level of their LC(50).