Author: Haakonde Titus
Citation Style For This Article: Haakonde T. Preliminary Assessment of Uranium Contamination in Drinking Water Sources in the Vicinity of Uranium Mine in Siavonga District, Zambia and the Associated Health Risks. The Health Press Zambia Bull. 2020; 4(4); pp 27
Contamination of drinking water by Uranium (U) has attracted global attention owing to its chemical toxicant and radio-toxicant behaviour in humans. Concentrations of U in water were assessed and health risks due to exposure through consumption of contaminated were determined.
In the current study, 120 drinking water samples collected from different water sources in some parts of Siavonga District in Zambia were measured using inductively coupled plasma mass spectrometry. United States Environmental Protection Agency (USEPA) deterministic risk approaches were used to determine the health risks associated with exposure to U through the consumption of contaminated water.
The mean concentration of U in water sources showed the decreasing trend: streams (135.30µg/L) > dams (115.62µg/L) > boreholes (111.31 µg/L) > shallow wells (110.03 µg/L). The levels of U in all the samples exceeded the safe limit for drinking water recommended by WHO indicating that the water in the studied area is not safe for drinking and cooking purposes. The estimated chronic daily intakes of U through water consumption showed the decreasing order: streams (3.62 µg/kg- bw/day) > dams (2.79 µg/kg- bw/day) > boreholes (2.68 µg/kg- bw/day) > shallow well (2.65 µg/kg- bw/day). Equally, the current study showed that the mean target hazard quotients (THQ) in all water samples exceeded the safe limit (THQ > 1) implying that the consumers of such water were at a greater risk of potential health effects. The carcinogenic risks from U at most of the drinking water sources were higher than acceptable ranges (10-6), indicating an increased risk of cancer for the population in the study area.
The current levels of U in drinking water sources stretching from the shores of Lake Kariba to Chirundu- Siavonga Border in Siavonga district in the Southern Province of Zambia implies that the condition is much frightening and severely affecting humans, animals and aquatic life.