Chemical quality assessment of major brands of bottled mineral water available in the Ethiopian market

Assessing bottled mineral water with drinking water guidelines set by the World Health Organization (WHO) and the Ethiopian Standard Agency (ESA) are highly relevant for practitioners, bottling companies, managers, regulators, and policymakers regarding water supply particularly bottled water. The present study was carried out to report the physicochemical quality of six branded bottled mineral water widely available in the Ethiopian market and compare them with drinking water standards. The investigated physicochemical parameters were pH, electrical conductivity (EC), total dissolved solids (TDS), chloride ion (CL - ), nitrate ion (NO3 - ), potassium (K+ ), sodium (Na+ ), zinc (Zn+ ), iron (Fe3+), calcium (Ca2+) and magnesium ion (Mg2+) using standard analytical techniques. Flame Atomic Absorption Spectroscopy (FAAS) was used to determine the number of metal elements. The Ultra Violet-Visible Spectrophotometer (UV-VIS) analysis was used to determine the amount of NO- in the bottled mineral water. The TDS and CL-values were determined by using gravimetric and volumetric methods. The study results revealed that the values of the quality parameter concentrations measured experimentally were slightly varied from the labeled values on the bottle. However, all brands were within EAS and WHO limit values for drinking water. The calculated correlation coefficient between the bottled water and the soil sample, between some dissolved solids and the TDS concentration in bottled mineral water, and between TDS and the pH concentration in bottled mineral waters was 0.99, 0.77 and 0.94, respectively. The study also verified that all the studied bottled water brands are safe for human consumption.