Health Risk Assessment of Trace Metals in Bottled Water: Toxicological Indices, Multivariate Modeling, and Monte Carlo Simulation with R software studies in urban population of Awka, Nigeria

Abstract Clean water is the most important inorganic substance for plants and animals, including humans, and the life of all living organisms depends on it. However, water is not naturally found pure, but always contains foreign components. In this study, seven commercial bottled water brands (ranging from 60 to 75 cL) were sampled across Awka city in Anambra State, Nigeria, to determine the concentration of six heavy metals (Manganese, Cadmium, Nickel, Chromium, Lead, Zinc) and evaluate their potential health risks to human consumption. The concentration ranges (in ppm or mg/L) for Mn, Cd, Ni, Cr, Pb and Zn were: 0.047–0.297, 0–0.024, 0.024–0.068, 0.012–0.056, 0.010–0.030 and 0.010–0.016 respectively. The heavy metals (HMs) concentration in this study was compared with other national and international studies on bottled water and other drinking water sources. Additionally, the results of non-carcinogenic health risk assessments using the Hazard Index (HI) and the Incremental Lifetime Cancer Risk (ILCR) indicated that the concentration of HMs in many of the samples pose adverse health effects (particularly in children than in the adults), especially as they bio-accumulate. This then suggests that the consumption of these bottled water brands may result to carcinogenic risks over a lifetime, particularly in children due to their lower body weight. Furthermore, this study contributes to the monitoring of SDG 6 (Clean Water and Sanitation) and SDG 3 (Good Health and Well-being) by identifying critical contamination pathways and evaluating the safety of commercial drinking water in urbanized African settings.