[Urban atmospheric pollution and public health: epidemiologic data].

Air pollution which is generated by car traffic of by various industries is susceptible to alter several functions of the respiratory cells. This has been demonstrated in several studies in vivo, in animal models or in human volunteers. However, the results of epidemiological studies in which the impact of air pollution on human health and particularly on the respiratory system (e.g asthma or respiratory infections), are unclear. Short term epidemiological studies have shown that air pollution can be responsible for some asthma symptoms such as cough and shortness of breath in known asthmatics, particularly in patients with mild rather than severe asthma. Moreover, these studies do not demonstrate than air pollution is responsible for the increase prevalence of asthma which has been reported these last 20 years. Concerning the relationships between air pollution and respiratory infections, the epidemiological studies are also contradictory.