ASSESSMENT OF INDOOR AIR POLLUTION FROM CHARCOAL COMBUSTION IN DAR ES SALAAM CITY, TANZANIA: A CASE STUDY OF MANZESE WARD.

Abstract

This study was conducted to determine the level of indoor air pollution due to cooking using charcoal inside the houses of Manzese in Dar es Salaam, Tanzania. A pilot system which was also used in trying to evaluate various technological options with the purpose of reducing indoor air pollution. The structured questionnaire was used to collect the household survey data. Microdust Pro (model 176106A, high range version) and gas analyser KANE900 Plus were used to measure the emissions (PM10 CO, NOx and SO2) from combustion. The air extraction fan (Vents 100K1 Axial fan) was used in the pilot system for pollutants removal. It was found that the usage of charcoal as the source of energy for cooking was very high in Manzese (82.2% of the dwellers).The number of households representing 53.3% and 95.9% were found to cook their food outside during the dry season and inside during the rainy season respectively. The overall hourly average CO concentration for the selected houses was 134±52 mg/m3 during cooking which is higher than the hourly recommended WHO guideline of 30mg/m3. The PM10 concentrations during cooking in all houses ranged from 1.22mg/m3 to 1.46mg/m3 with an overall hourly average concentration of 1.37 mg/m3 exceeding the WHO 24 hours guideline mean concentration of 0.05mg/m3. Also measurements for SO2 and NOx concentrations (mg/m3) were taken in the sampled houses and were found to be higher than the WHO guidelines. Air extraction fan lowered the CO and PM10 concentrations from 206mg/m3 to 28mg/m3 and 1.14mg/m3 to 0.26mg/m3 correspondingly. It was concluded that awareness should be given to the people on the health effects caused by burning charcoal in the indoor environment, the adoption of air extraction fans should be encouraged so as to minimize pollution levels in the indoor environment and encourage Manzese dwellers to have outside facility for cooking whenever possible.