Geochemical Profiling and Health Risk Assessment of Heavy Metals in Yemeni Bottled Water: A Multivariate Statistical Approach

Abstract

The quality and safety of bottled drinking water are of growing concern in Yemen due to increasing dependence on groundwater resources and potential contamination by trace metals. This study presents an integrated secondary analysis of previously published inductively coupled plasma–mass spectrometry (ICP-MS) data to evaluate the concentrations of seven heavy metals (Hg, Cd, Cr, Ni, Al, Co, and Cu) in 27 bottled water brands marketed in Yemen, combining health risk assessment with multivariate statistical analysis. Human health risks were assessed through chronic daily intake (CDI), hazard quotient (HQ), hazard index (HI), incremental lifetime cancer risk (ILCR), and total carcinogenic risk (TCR). In addition, multivariate statistical techniques, including principal component analysis (PCA) and hierarchical cluster analysis (HCA), were applied to identify contamination sources and classify bottled water brands according to their geochemical characteristics. The results revealed considerable variability among brands, with mercury and cadmium exhibiting elevated concentrations in several samples. Non-carcinogenic risk assessment showed that children were more vulnerable than adults, although average exposure levels generally remained within acceptable limits. Carcinogenic risk assessment indicated that the mean ILCR and TCR values for Cd, Cr, and Ni were within the internationally accepted risk range. PCA identified three major controlling factors explaining 71.9% of the total variance, corresponding to infrastructure-related, anthropogenic, and lithogenic influences. HCA and heatmap analyses further distinguished stable background-quality brands from geochemically impacted and anomalous samples. Overall, most bottled water brands exhibited acceptable quality; however, the occurrence of elevated Hg and Cd concentrations in specific products highlights the need for continuous monitoring and source-based management strategies to ensure long-term consumer safety in Yemen.