Air pollution and respiratory health of school children in industrial, commercial and residential areas of Delhi

Air pollutants may cause severe respiratory problems in the children during their developmental stages. In this study, the respiratory health of school children belonging to three different localities namely industrial, commercial and residential areas of Delhi City was assessed by questionnaire survey and lung function test. The outdoor air pollution data from the National Ambient Air Quality Monitoring (NAAQM) stations was used for the study, which were located within 1-km distance from the selected school sites. Indoor air quality monitoring has also been done at classrooms for particulate matter (PM10), sulphur dioxide (SO2) and nitrogen oxides (NOx). Indoor and outdoor PM10 concentration at schools in commercial area (815 +/- 354.45 and 337 +/- 85 mu g/m(3)) was ten times above the NAAQM limits of 100 mu g/m(3). PM10 concentration was lower in industrial (694.6 +/- 322.9 and 274 +/- 78 mu g/m(3)) and residential (534.3 +/- 94.22 and 197 +/- 48 mu g/m(3)) areas. However, levels of SO2 and NO2 were under the permissible limits. The findings also revealed that the children living in the commercial area had higher respiratory symptoms as compared to industrial and residential areas. The respiratory symptoms were found to have a statistically significant positive association with PM10 levels in the air.