Fifteen asthmatic patients of atopic type at the Tokyo Kyosai Hospital were followed up their symptoms through the asthma-patient-diary prepared by the present authors during the period from Nov. 18, 1969 to Feb. 6, 1970, and the hourly changes of air pollutants (SO₂ and suspended particles) were measured and recorded automatically by an air pollution recorder settled in this hospital.
The day of ingravescent of symptoms especially with asthmatic attacks was checked for each patient during the observation period, and the patient-number of ingravescent in each day was recorded and analysed for the health effect of air pollution. The asthmatic patients showed a tendency to develop critical symptoms on the day when severe air pollution as SO₂ over 0.2 ppm in maximum took place (among the day) and also when suspended particles were over 50% by the measurement of transparency decrease of filter paper. The influence of severe air pollution upon asthmatic attack seemed to continue to the subsequent day.
Although the lung function tests using a Benedict Roth respirometer as well as Body pletysmograph were investigated upon over 6 patients, no significant correlation was recognized between the data of the tests and the air pollution factors.