Lithium in drinking water sources in rural and urban communities in Southeastern Nigeria

Abstract

There is a dearth of data on lithium content of domestic water sources in Nigeria. This study reported the lithium concentration in ground and surface water sources used for drinking in Southeastern Nigeria. Thirteen (13) natural springs, 24 streams, 7 hand-dug wells and 80 boreholes, making a total of 124 water samples were collected from strategic locations and analysed by ICP-OES. The distribution of lithium according to water sources and lithostratigraphic units as well as dietary contribution of lithium through drinking water was investigated. Average lithium concentrations in water samples from all sources were between 0.09 and 1.54 μg/L (overall mean ± SEM: 1.0 ± 0.2 μg/L). Results according to the geological formations of the areas studied indicated that only water sources located within the Benin Formation and Bende-Ameki Formation contained lithium in the range of <0.21-7.24 and < 0.21-1.97 μg/L respectively, whereas lithium was not detected in samples located within the Nsukka and Mamu lithostratigraphic units. Total intakes of lithium from water consumption (0.64 L for children and 2 L for adults) for all water sources were 79 and 247 μg/day for children and adults respectively, while the average daily intake of lithium from the water sources ranged from 0.004 to 0.066 and 0.002-0.044 μg/kg body weight for children (15 kg) and adults (70 kg) respectively. Drinking water in the study areas contributes only about 0.02-0.47% of the U.S. EPA estimated daily intake (9.3-44.3 μg/kg) of Lithium.

Keywords: Dietary contribution; Drinking water; Geological formation; Lithium; Nigeria.