Air pollution and children's health in São Paulo (1986-1998).

Air pollution in the conurbation of São Paulo, Brazil, with 17 million inhabitants, has been measured from air quality monitoring stations. In three contrasted sample areas, children's respiratory health parameters were collected to assess the role of air pollution in 1986. Twelve years later, in 1998, a similar study was undertaken to evaluate the impact of pollution control programs on the respiratory symptoms of children living in the same neighborhoods previously studied. Results indicated that pollution control programs were in part neutralized by increased number of cars and that the control of a single pollutant was not enough to protect children's health. In the area where both particulate matter and sulfur dioxide levels decreased, there was a reduction in the prevalence of respiratory symptoms.