Ecological and health risk assessment of rare earth elements in Kaifeng, Henan Province: a Monte Carlo probabilistic approach
摘要
As rare earth elements (REEs) are increasingly used in production and daily life, the threat that REEs in urban soil pose to human health has become increasingly prominent. This study focused on urban soils in Kaifeng City. A total of 70 surface soil samples were collected to determine the concentrations of 13 REEs and conduct a risk assessment. To reduce the impact of uncertainties, Monte Carlo simulation was incorporated into the US EPA model to perform uncertainty analysis for health risk assessment. The results showed that: (1) The average total concentration of REEs in the soil of Kaifeng City was 139.36 mg kg−1, and the ecological risk index ranged from 33.98 to 227.01. (2) The average daily doses for adults and children were 0.208 μg kg−1 d−1 and 1.39 μg kg−1 d−1, respectively, both of which were far below the reference threshold (70 μg kg−1 d−1). (3) Monte Carlo simulation revealed that the mean ecological risk index and average daily human exposure dose were similar to the corresponding values obtained from deterministic analysis. The sensitivity contribution rate of exposure parameters was around 80%, remarkably higher than that of REEs concentrations. Consequently, the influence of exposure parameters on the evaluation results should not be underestimated.