1. We have good reason to be suspicious observed in 1988 in an editorial titled
2. of the contemporary role of air pollutants "Why Study the Epidemiology of
3. but proof is something else. We have no Asthma?" that much contemporary atten
4. reason to suppose that our knowledge of tion was being concentrated on mechanis
5. agents that might induce or increase hyper- tic research in asthma and relatively little