Bacteriological and chemical quality of packaged water produced in Lusaka, Zambia and associated quality control measures

Abstract

Many people in the world lack safe basic drinking water sources and rely on untreated water sources. Unsafe drinking water is responsible for transmission of diseases such as Cholera, Dysentery and Typhoid. Packaged water can be considered as an alternative to other water sources if measures are put in place to ensure its safety for human consumption. Studies prior to this one focused on the quality of water sold in Lusaka regardless of the district the water is produced from. There has also been less focus on the quality control measures that may influence quality. A cross-sectional study was conducted to assess the bacteriological and chemical quality of packaged water produced in Lusaka and associated quality control measures. Water samples from 17 companies producing packaged water in Lusaka were analyzed for total and feacal coliforms as well as concentrations for Lead, Chromium and Cadmium. Stata version 15 was used for data analysis. The fisher’s exact test was used to test for associations between the quality of packaged water and quality control measures. The study found that 35.3 percent of the packaged water produced in Lusaka did not comply with the standard for drinking water on bacteriological quality. It also found that the concentrations for Lead were less than 0.01mg/l in all the 17 samples, thus compliant to WHO/ZABS standards. Concentrations of Chromium were between 0.002mg/l and 0.62mg/l and compliance to the standard was 11.8 percent. Concentrations for Cadmium were as low as 0.009mg/l and as high as 0.2mg/l as such, non-compliant. All brands of packaged water from companies inspected quarterly by Lusaka City Council were compliant to the bacteriological standards of drinking water. Packaged water produced by companies that own bacteriological laboratories accounted for 47.1 percent of satisfactory results while only 17.3 percent were satisfactory from companies without bacteriological laboratories. None of the companies had means of removing heavy metals from water during processing. Both the bacteriological and chemical quality of the packaged water need to be improved to safeguard the health of the people. Processing of the water should therefore target removal of all bacteria and heavy metals. Government agencies should also monitor the companies regularly to ensure compliance to standards.