The impact of an abandoned mercury mine on the environment in the Xiushan region, Chongqing, southwestern China

Abstract

Mercury (Hg) contamination is a serious problem at Hg mining area of Xiushan County, Chongqing, southwestern China. Concentrations of total mercury (THg) and methylmercury (MeHg) in paddy soil, surface water, and rice (grain) samples wereanalyzed to exhibit regional distribution of Hg contamination. Simultaneously gaseous elemental Hg (GEM) in ambient air in the vicinity of sampling sites were measured in situ. Hg concentrations in surface water were highly elevated ranging from 13-2390 ng/L, and MeHg concentrations varied between0.17-1.1 ng/L. Dissolved Hg and MeHg concentrations in surface water ranged from 4.7-470 ng/L and 0.14-0.35 ng/L, respectively. High THg and MeHg concentrations were also obtained in paddy soils from mining areas, ranging from 0.45-68 µg/g and 0.13-4.8 ng/g, respectively. Similar to high concentrations in water and soil, Hg in rice (grain) ranged from 4.7-550 ng/g and MeHg from 2.9-26 ng/g. Elevated Hg concentrations in rice, as a staple food to residents, confirmed that rice consumption could be a vital pathway of MeHg exposure to native populations. The spatial distribution characteristics of Hg and MeHg pollution in the local environment indicated the origin from historic Hg mining sites in the Xiushan area.

Distribution of Mercury and Methylmercury in Farmland Soils Affected by Manganese Mining and Smelting Activities

“…These values were higher to the background value of 0.069 mg kg −1 in agricultural soils in Chongqing [ 14 ] and also had an over-limit ratio of 20% compared to the risk screening value of the Chinese control standard [ 27 ]. Compared with other Hg mining areas in China, the concentrations in the present study are much lower than those in Xiushan (9.8 ± 17.5 mg kg −1 ) [ 15 ] and Wanshan (31.00 mg kg −1 ) [ 7 ] ( Table S1 ). These results indicate that mining and smelting of Mn ore have resulted in obvious Hg accumulation in farmland soil in the study area.…”

“…Soil MeHg concentrations in the mining area and smelting area were 0.36 ± 0.39 and 0.88 ± 1.00 μg kg −1 , respectively. These concentrations were higher than background concentrations in the Chongqing area (0.41 ± 0.19 μg kg −1 ) [ 28 ], and lower than those in Hg mining areas in Xiushan (1.36 μg kg −1 ) [ 15 ] and Wanshan 2.8 μg kg −1 [ 7 ]. The ratio of MeHg to THg (%MeHg) in soils is an indicator of the Hg methylation efficiency [ 29 ].…”

“…Little information is available about the regional distributions of THg and MeHg in farmland soils affected by Mn mining and smelting activities. Two studies conducted in the Xiushan Hg mining area, downstream from the Mn mining area, have shown that paddy soils in this area are polluted with elevated Hg concentrations [ 15 , 16 ]. However, these studies did not investigate the contributions of Mn mining and smelting activities, which are dominant pollution sources.…”

Distribusi Pencemaran Merkuri Di Das Batanghari Sumatera

“…Pencemaran merkuri di perairan menjadi masalah dengan terbentuknya metil merkuri yang berbahaya bagi ekosistem dan manusia [1], [6]. Keberadaan merkuri di lingkungan mempunyai berbagai bentuk, baik sebagai anorganik maupun organik dengan potensi racun yang berbeda [4], [7], [8]. Selain itu, merkuri juga dapat bertahan lama di atmosfer dan dapat ditransportasikan secara global [9].…”

The use of a geostatistical model supported by multivariate analysis to assess the spatial distribution of mercury in soils from historical mining areas: Karczówka Mt., Miedzianka Mt., and Rudki (south-central Poland)

“…Abandoned mining areas belong to the most dangerous uncontrolled sources of pollutants (Kim and Hyun 2015). For several years, these areas have gained significant attention to scientific community (Bori et al 2016; Bosso and Enzweiler 2008; Castillo et al 2013; Gałuszka et al 2016; Sheoran et al 2010; Xu et al 2017). This is not surprising, given the fact that many of them have not been submitted to the recovery program.…”