Trend of Air Pollution and its Effect on Hum.an Health in Hiroshima Prefecture : A Retrospective Study in the Cities of Otake, Kure, Mihara, Takehara, Fukuyama and Kaita Town, 1977-1992

The evaluation of adverse health effects resulting from exposure to relatively low levels of ambient air pollution is currently a major concern. By using methodology that directly addressed the time series nature of data, this study investigated the association between ambient air pollution and respiratory symptoms and eye, nose, throat irritation symptoms. Health effects were determined by using the air quality data from ambient monitoring stations located within the Hiroshima Prefecture area. The air pollution data chosen for this study were the mean of annual average concentrations of sulfur dioxide (SO2), nitrogen dioxide (NO2), suspended particulate matter (SPM) and photochemical oxidants (Ox). The health data were extracted from the Hiroshima Community Health Study conducted in the cities of Otake, Kure, Takehara, Mihara, Fukuyama and Kaita Town during 1977-1992. The Community Health Study data were obtained by using a Japanese translation of the British Medical Research Council (BMRC) Questionnaire. The analysis was limited to the investigation of the health symptoms reported by subjects and the mean annual average concentrations of ambient air pollution in each study area. The results indicated a significant association between SO2 levels and lacrimacy symptoms (p<0.05), runny nose (p<0.05) and cough symptoms (p<0.05). This study also found a significant association between Ox and phlegm symptoms reported by the subjects (p<0.01). In contrast, the results found that there was a negative correlation between NO2 levels and phlegm symptoms reported by subjects. In conclusion, moderate annual changes in SO2 and Ox levels induce a significant increase of health symptoms in the local community.