Contaminated site-induced health risk using Monte Carlo simulation: evaluation from the brownfield in Beijing, China

The occurrence of contaminated sites has caused serious public health problems, and there are significant health risks. This paper applies Monte Carlo simulations to evaluate the impact of pollutants on human health at a contaminated site in Beijing, China. In this study, a total of 429 soil samples were collected. The exposure routes considered were oral ingestion and skin contact. The log-normal distribution or triangular distribution was adopted to convert exposure parameters into statistical parameters, and the final risk probability was estimated through Monte Carlo simulations. The results show that the 95th percentile risk indexes of As, Ni, Zn, and Hg are 1.22E-1, 5.05E-3, 5.10E-4, and 1.69E-1, respectively, which are all within acceptable levels. The maximum values of As and Hg are 2.15E+0 and 1.04E+0, respectively, with a 5% and 4% probability, respectively, of exceeding the acceptable health risk level. In theory, it is believed that they do not pose a potential threat to human health. Nevertheless, As and Hg in soil are still major pollution sources. The results also show that C (pollutant concentration), AT (mean action time), and ED (exposure duration) are the three parameters with the highest sensitivity to the health risk value. The results of this study can help to improve soil risk control measures and remediation decisions for contaminated sites to reduce the environmental risk in contaminated areas.