Abstract
In March 1986 we investigated the distribution of levels of suspended particulate matter (SPM) and nitrogen dioxide (NO2) inside and outside the homes closely located along two major arterial roads, Mito Kaido and Kan-nana Dori, in Katsushika, Tokyo. We surveyed 50 homes a week, a total of 150 homes for three weeks. Determinations of SPM and NO2 were carried out for 4 continuous days, i. e. Monday 8 a. m. to Friday 8 a. m. Coarse (≥2.5 μm) and fine (≤2.5μm) particles were separately collected on 8 μm-poresize nucleopore filter, by using portable aerosol samplers. NO2 was collected with small passive NO2 samplers.
Averageulevels of these two air pollutants had means of 23.6 μg/m3 (indoor coarse particle), 35.4μg/m3 (indoor fine particle), 43.7ppb (indoor NO2) and 27.7 ppb (outdoor NO2). Indoor smoking and the use of unventilated heaters apparently increased levels of fine particle and NO2. Indoor climate was found to be also influenced by the house structure. The increases of these pollutants levels due to smoking or heating were observed in reinforced concrete houses because of the air tightness.
By excluding the effects of smoking and heating, indoor fine particle and NO2 and outdoor NO2 were found higher in homes which were closely (within 20 m) located along the roads.
The present results indicate a possible association between the distance from the roads and the levels of fine particle and NO2.
