Bottled water safety evaluation: A comprehensive health risk assessment of oral exposure to heavy metals through deterministic and probabilistic approaches by Monte Carlo simulation.

ABSTRACT

The consumption of bottled water has witnessed substantial global expansion in recent times. This study aimed to quantitatively evaluate the concentrations of eight heavy metals (As, Ba, Cd, Cr, Mn, Mo, Ni, and Zn) in 71 high-consumption bottled water brands in Iran. Non-carcinogenic and carcinogenic risk assessments were conducted using both deterministic and probabilistic approaches. Point estimation utilizing the Hazard Quotient (HQ) formula and sensitivity analysis employing the Monte Carlo Simulation (MCS) method through 10,000 repetitions in Oracle Crystal Ball® was used to ascertain the health risks associated with heavy metal exposure. Heavy metal concentrations were quantified through Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). HQ point estimation results indicated that Cr exhibited the highest mean HQ value, whereas Cd demonstrated the lowest. In the probabilistic approach, the highest 95 percentile values were observed for Cr and Mo at 3.9E-01, while the lowest values were recorded for Cr and Mn at 1.10E-02. Heavy metal concentrations emerged as critical factors influencing non-carcinogenic and carcinogenic risks across all groups in the sensitivity analysis. The findings highlight the need for ongoing monitoring, research, and targeted regulations to address health risks from heavy metal exposure in bottled water and ensure public well-being.