[Air pollution and prevalence of nonspecific respiratory diseases in childhood].

The difficulties of defining chronic nonspecific lung diseases (CNSLD) and covering patients with these diseases are discussed. The comparison of the results of epidemiologic investigation from different investigators is full of problems. In extensive epidemiologic investigations a remarkable parallelism was found between the prevalence of CNSLD and the degree of air pollution. Furthermore the influence of climatic factors such as average annual temperature, air humidity, wind velocity, especially in reference to the content of SO2 and sedimentation dust could be stated. For the influence of microclimate on the morbidity rate the habits of smoking in the family and heating were found to be important.