Study on the Ct-effect relation of acute lung injury induced by phosgene in mice

Objective By comparing with the effects of two parameters(exposure concentration and exposure time)of concentration × time(Ct)product on degree of acute lung injury of mice induced by phosgene,to study the mechanism of acute lung injury induced by phosgene.Methods The mice were respectively exposed to phosgene under the different Ct product and the same Ct product but different exposure concentrations and exposure times.The wet/dry radio of lung,the enzyme activity of MPO in lung and the content of malondialdehyde(MDA)in lung and serum were detected.Results With Ct product increasing,death rate of mice increased significantly(P0.001).Under the same Ct product of 12 ml·min,death rate increased significantly(P0.01)by the exposure concentration.The wet/dry radio of lung increased significantly(P0.001).The enzyme activity of MPO and the content of MDA in lung were both higher than that of the control(P0.05).Conclusions With Ct products increasing,death rate of mice exposed to phosgene increased.However,under the same Ct product,exposure concentration and exposure time had different effects on degree of lung injury.It was found that exposure concentration affected degree of lung injury much more than exposure time.Exposure to high concentration of phosgene for short time would induce more severe lung injury than that to low concentration of phosgene for long time.