Anthropogenic mercury emissions in China

Abstract

An inventory of mercury emissions from anthropogenic activities in China is compiled for the year 1999 from official statistical data. We estimate that China's emissions were 536 (7236) t of total mercury. This value includes open biomass burning, but does not include natural sources or re-emission of previously deposited mercury. Approximately 45% of the Hg comes from non-ferrous metals smelting, 38% from coal combustion, and 17% from miscellaneous activities, of which battery and fluorescent lamp production and cement production are the largest. Emissions are heaviest in Liaoning and Guangdong Provinces, where extensive smelting occurs, and in Guizhou Province, where there is much small-scale combustion of high-Hg coal without emission control devices. Emissions are gridded at 30 Â 30 min spatial resolution. We estimate that 56% of the Hg in China is released as Hg 0 , 32% as Hg 2+ , and 12% as Hg p. Particulate mercury emissions are high in China due to heavy burning of coal in residential and small industrial settings without PM controls. Emissions of Hg 2+ from coal-fired power plants are high due to the absence of flue-gas desulfurization units, which tend to dissolve the soluble divalent mercury. Metals smelting operations favor the production of elemental mercury. Much of the Hg is released from small-scale activities in rather remote areas, and therefore the activity levels are quite uncertain. Also, emissions test data for Chinese sources are lacking, causing uncertainties in Hg emission factors and removal efficiencies. Overall, we calculate an uncertainty level of 744% (95% confidence interval) in the estimate of total emissions. We recommend field testing of coal combustors and smelters in China to improve the accuracy of these estimates.

Mercury Pollution in China

“…In China, Hg is well recovered in large-scale mining processes that use amalgamation, with an emission factor of ~0.79-g Hg/g Au production. However, Hg is poorly recovered in the small-scale (artisanal) mining process, and the emission factor is ~15-g Hg/g Au production (9). In 1999, only ~20 t of Au was produced from large-scale mining processes, and ~16 t of Hg emissions resulted (9).…”

“…However, Hg is poorly recovered in the small-scale (artisanal) mining process, and the emission factor is ~15-g Hg/g Au production (9). In 1999, only ~20 t of Au was produced from large-scale mining processes, and ~16 t of Hg emissions resulted (9). Although artisanal Au-mining activities have been officially prohibited since 1996, a few illegal workshops still operate in remote areas.…”

“…Of the Hg emitted from coal combustion in China, 51% comes from industrial use, 33.6% from power plants, 9.8% from residential use, and 5.6% from other uses (9).…”

Rice consumption contributes to low level methylmercury exposure in southern China

“…Its annual Hg emission reached 604.7 t in 2000, accounting for 28% of the global emissions (Pacyna et al, 2006). Coal combustion and non-ferrous metal smelting are the most important anthropogenic sources (Streets et al, 2005). The large Hg emissions have resulted in serious environmental Hg pollution in China (Feng, 2004;Jiang et al, 2006;Zhang and Wong, 2007).…”

The impact of sewage irrigation on the uptake of mercury in corn plants (Zea mays) from suburban Beijing

“…Average soil and root Hg levels for the current study were both near the minimum levels measured in Guizhou Province, which may be explained by lower atmospheric Hg emissions in Beijing. Streets et al (2005) reported the 1999 annual anthropogenic Hg emissions for each province in China. Higher total Hg emissions were recorded for Guizhou Province compared to Beijing (Beijing ¼ 8.83 t, Guizhou ¼ 39.00 t), while the percentage of Hg 2þ deposited locally was approximately equal (Beijing: 22%, Guizhou: 24%).…”