Effects of modern and ancient human activities on mercury in the environment in Xi'an area, Shannxi Province, P.R. China

Samples of water, soil, sediment, and pomegranate were collected from Xi'an and the Qinshihuang Mausoleum in Shaanxi Province, China to assess the effects of human activities on mercury in the environment. The total mercury concentrations ranged from 3.9 to 992.7 ng L −1 for the water samples, 40.6 to 2204.0 ng g −1 for the soil samples, 14.2 to 376.7 ng g −1 for the sediment samples, and 0.22 to 1.74 ng g −1 for the pomegranates samples. The higher values in the water samples collected from the rivers closer to and downstream of the city resulted from wastewater discharges. The effects of the mercury buried in the Qinshihuang Mausoleum thousands of years ago on the environment were neither significant nor widespread. Immediate actions should be taken to stop the direct and continuous discharges of industrial and residential wastewaters to prevent mercury and other pollutants from accumulating and spreading in the area. Urban activities are sources of mercury to the environment and the pomegranates grown over the burial mound of the Qinshihuang Mausoleum are not mercury-contaminated.