Health risk assessment due to uranium contamination in groundwater: MATLAB based Monte-Carlo simulations

Uranium contamination is a growing concern due to its inherent toxicity, which poses a significant threat to human health. The health risk assessment due to uranium contamination in groundwater of Mansa district, Punjab (India) is investigated. The LED LF-2a Fluorimeter model by Quantalase (Indore) was used for measurement of uranium concentration in groundwater collected in October 2021 from twenty-six locations. A comparison is conducted between the deterministic and probabilistic approaches since the deterministic approach might either underestimate or exaggerate the risk estimation. Monte-Carlo simulations are used to curtail the associated uncertainties in the data. The simulations are carried out in MATLAB for risk assessment and sensitivity analysis. The deterministic and probabilistic approaches are used to calculate hazard quotient, excess cancer risk and annual effective dose. Using probabilistic approach, the hazard quotient for male and female at 5th percentile is 4.36 and 3.81, respectively. Similarly, the hazard quotient for male and female at 95th percentile is 38.95 and 34.26, respectively. The mean hazard quotient is 18.45 and 15.68 for male and female, respectively, using deterministic approach. The hazard quotient is greater than 1 for both genders (male and female) and excess cancer risk is also higher than 10−4 using both deterministic and probabilistic approaches. The annual effective dose using deterministic approach is 0.23 mSv year−1 whereas using probabilistic approach, the 5th and 95th percentile is 0.56 mSv year−1 and 4.33 mSv year−1, respectively. The sensitivity analysis indicated that the overall risk is more sensitive to concentration of uranium in groundwater and the exposure frequency. This study emphasises on the hazards posed to humans by the ingestion of uranium contaminated groundwater, hence stressing the urgency for taking actions to protect the population of the study area.