Contribution of groundwater to dietary requirements of essential metals in Lagos and Ogun States, Nigeria.

Knowledge of dietary intakes of essential elements in groundwater is important for proper assessment of the actual contribution of drinking water to daily nutrient requirements. This study assessed the daily intake of nutritional elements in drinking groundwater of Lagos and Ogun States of Nigeria. One hundred and seventy (170) water samples were collected and analyzed for thirteen (13) nutritional elements (K, Mg, Ca, Co, Fe, Cu, Zn, Mo, Se, Na, Mn, Cr, and I) by Inductively Coupled Plasma-Mass Spectrometry (ICP/MS). Chronic daily intake CDI of the nutritional elements was higher for children and infants than adults in all cases. Percentages of tolerable daily intake reference value (TIRV) obtained for Lagos State groundwater were Mg 0.425%, Ca 0.309%, Fe 14.0%, Cu 1.84%, Zn 6.25%, Mo 0.057%, and Mn 1.08%; for Ogun State groundwater, % TIRV were Mg 1.99%, Ca 0.586%, Fe 81.1%, Cu 2.12%, Zn 9.21%, Mo 1.16%, and Mn 0.023%. The order of dermal absorption by an adult in Lagos when the water is used for bathing daily was Cr > Mn > Fe > Zn > Cu while the order in Ogun was Fe > Mn > Zn > Cu > Cr. The research concluded that groundwater alone cannot provide enough essential elements for human dietary needs in the study area.
(© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)