1915 Journal of the American Medical Association  
smoke greatly increases the incident severity and mortality of acute diseases of the air passages ; pneumonia and bron¬ chitis increase directly as smoke increases. The purification of the atmosphere should therefore receive the same attention as pure food and pure water are receiving, for it is just as important.
doi:10.1001/jama.1915.02580180079039 fatcat:4hrpawxmfbafzkogyjucx3jxcm