A survey of mercury pollution from fluorescent lamps disposal in selected sites in Nairobi
Abstract
The high cost of electricity has necessitated most households to opt for fluorescent bulbs as opposed to the normal incandescent lamps. The disposal of phosphor and particularly the toxic mercury in the tubes is an environmental issue of concern. Government regulations in many areas require special disposal of fluorescent lamps separate from general and household wastes. Kenya however, lacks such regulations.
A source specific environmental risk analysis was performed in selected sites within Nairobi with high fluorescent bulb usage, to ascertain the local levels of mercury in ambient air. These were Times Tower building and the Sunken Car Park. Passive sampling of ambient air using 0.1 % potassium permanganate in IN sulphuric acid as the dissolving solution was carried out in the selected sites over April to June 2010. Cold vapour atomic absorption spectroscopy was used to determine ambient air mercury contamination levels.
The results obtained for both Times Tower and the Sunken Car Park indicated mercury levels above the average permissible concentrations for occupational (0.05 mg/m') or continuous environmental exposure (0.015mg/m3) (WHO, 1976). The results obtained at Times Tower, (1.3440 mg/m'') for the month of April prior to sensitization confirms high mercury air contamination associated with lack of sensitization. After sensitization on the need to separately dispose the dead lamps, there was an overall decrease of 5.72 times.
The Sunken Car Park where dumping was uncontrolled was used as a reference. The mercury concentration decreased by 1.09 times over the study period. This was attributed to the fact that no sensitization was done for those responsible for the disposal of the florescent bulbs and garbage. The impact of sensitization was evidenced by the sharp drop in mercury concentrations at Times Tower holding ground in the subsequent months of study. This shows that mercury pollution can be controlled through awareness and proper disposal procedures.
Publisher
University of Nairobi, Kenya