[Respiratory response to sulfuric acid and sulfate salts mist].

In order to investigate the effects of sulfuric acid and sulfate salts mist on the respiratory system, guinea pigs were exposed to acute conditions of sulfuric acid, ammonium bisulfate, ammonium sulfate, sodium bisulfate, sodium sulfate of 50mg-SO4/m3, respectively. Animals developed laboured breathing, only when exposed to acidic mist. Furthermore, it was shown that laboured breathing might be related to the acidity of mist. No significant differences in respiratory frequency (f), total respiratory system resistance (T. R. S. R) and pseudo-flow rate (Vpse) were observed between ammonium bisulfate (acidic) exposed group and ammonium sulfate (neutralized salt) exposed group, before laboured breathing development. Histamine content of lung and tracheal tissues were also examined. Tracheal histamine level of ammonium salts exposed group was reduced compared to the control group, but the relationship between laboured breathing development and histamine content was not observed.