Assessment of air pollution in residential areas of Kinondoni municipality in Dar es Salaam City, Tanzania

Abstract

The quality of the ambient air at residential areas has been assessed for Kinondoni Municipality in Dar es Salaam City. Three air pollutants namely Nitrogen dioxide (NO2), suspended particulate matter (SPM), and particulate lead (Pb) were measured in Mikocheni, Kijitonyama, Sinza, and Manzese. Saltzman, filtrations, and Atomic Absorption Spectrometric methods were correspondingly used for analysis of NO2, SPM, and
particulate lead. Results have shown that with exception of NO2, the other pollutants were present at levels above the WHO guidelines. The SPM concentration varies from 418.7 μg/m3 to 804.0 μg/m3 while the WHO
guideline value is 230 μg/m3. The particulate lead range from 7.4 to 12.0 μg/m3 exceeding the quarterly WHO standard of 1.5 μg/m3. Hourly average nitrogen dioxide concentration ranges from 16.0 μg/m3 to 74.0 μg/m3, which is below the WHO guidelines value of 200 μg/m3. The carcinogenic risk assessment due to particulate lead pollution was undertaken considering people who spend most of their time in the residential areas. The additional unit risk realised was 78.8 x 10-6 for adults and 25.1 x 10-6 for children, both scenarios showing additional risk higher than the United States of America Environmental protection agency (USEPA) acceptable risk of 1 x 10-6. The obtained additional unit risk is equivalent to 48 people getting cancer out of 606767 exposed adult population and 12 children out of 476746 exposed children in Kinondoni Municipality. From these results it can be concluded that Kinondoni municipality dwellers, are living in hazardous atmospheric environments.

Keywords: Particulate, lead, nitrogen dioxide, residential, carcinogenic risk assessment, air pollution.