Health risks of exposure to air pollutants among students in schools in the vicinities of coal mines

Abstract

Air pollution poses a serious threat to human health and the general ecosystem both in South Africa and globally. This is mostly caused by the mining and combustion of fossil fuels, such as coal. There are some known pollutants associated with coal mining and combustion that are emitted into the air, resulting in various health implications that affect children the most as they are the most vulnerable. In this study, the levels of certain air pollutants in schools in the vicinities of coal mines were assessed. A cross-sectional study design was adopted. Five schools were purposively selected for this study. Air samples were collected inside and outside the classrooms of each school. Radiello® passive air samplers were used to measure the levels of sulphur dioxide, nitrogen dioxide and ozone while filter pumps were employed for lead (Pb). Standard laboratory analytical methods were employed for the analysis. Estimates of the possible health risks resulting from exposure to airborne sulphur dioxide, nitrogen dioxide and ozone were performed using the United States Environmental Protection Agency Human Health Risk Assessment framework. The non-cancer risk of sulphur dioxide, nitrogen dioxide and ozone was determined using the hazard quotient. The results of this study revealed that sulphur dioxide, nitrogen dioxide and ozone were detected within and outside the classrooms at various levels. For example, the concentration of sulphur dioxide within the classroom ranged from 3.0 to 38 µg/m 3. Outside the classroom, sulphur dioxide levels detected were much higher ranging from 17 to 84 µg/m 3 . The results of the non-carcinogenic risks from exposure to nitrogen dioxide, sulphur dioxide and ozone via inhalation route were less than 1.0. The elevated levels of these pollutants in the vicinity of schools investigated should be a cause for concern for all the stakeholders in the education sector. Therefore, appropriate measures need to be taken urgently to safeguard the health of the concerned community.