An epidemiological survey to determine the prevalence of chronic bronchitis in a mixed mining and non-mining population of Carletonville on the Witwatersrand is described. Eight hundred and twenty-seven men over the age of 35 years were investigated.
Chronic bronchitis is shown to significantly more common in miners than in non-miners for every age and smoking category with the exception of the non-smoker no significant difference exists in the prevalence of chronic bronchitis between the mining and non-mining groups.
Smoking habits were found to have overwhelming effects on the prevalence of chronic bronchitis in both groups.
It is suggested that a synergistic interplay of smoking and general underground aerial pollution (rather than dust inhalation alone) is responsible for the excess prevalence of chronic bronchitis in the miner who smokes.