Relationships of air pollution to health: results from the Pittsburgh study

The evaluation of adverse health effects resulting from exposure to relatively low levels of regulated air pollutants is currently of major concern. The determination of short-term or acute effects is necessary for this evaluation. By using methodology that directly addressed the time series nature of the data, this study investigated acute health effects of daily levels of air pollution in Allegheny County, Pennsylvania, using both mortality and morbidity events as the adverse health response to ambient pollution. Health effects were determined using the air quality data for sulfur dioxide (SO2) and particulates as measured by the Coefficient of Haze from three monitoring stations located within the county. The mortality analysis provided a replication of a previous study performed in the New York area. The analysis was limited to the investigation of same day effects. Results indicated a possible association between heart disease mortality/morbidity and same day particulate levels. No association between SO2 and mortality/morbidity was seen at the present level of SO2. These findings were in agreement with those obtained in the New York City study and in a re-analysis of London winter data. The need for investigations of delayed effects and weather-mortality/morbidity relationships, as well as evaluation of hospital discharge record information, was stressed.