![]() Hg is released into the environment through human activities and via natural sources and processes, such as volcanoes and rock weathering. Īn improved understanding of the global mercury (Hg) cycle is important for our capacity to predict how regulatory efforts to reduce current emissions to air, water and land will affect Hg concentrations in environmental compartments, biota and humans. Hg is the only element in the periodic table to have its own environmental convention, i.e., the Minamata Convention on Mercury, thus highlighting the importance of the Hg pollution issue. Over the last few decades, considerable scientific knowledge has been developed on the sources and emissions of mercury, its pathways and cycling through the environment, human exposure, and impacts on the environment and human health. Moreover, mercury has the ability to be transported within air masses over very long distances. Mercury is recognized as a toxic, persistent, and mobile contaminant it does not degrade in the environment and becomes mobile because of the volatility of the element and several of its compounds. The general conclusions were drawn from a review of the literature and presented in this paper. Atmospheric contamination by mercury continues to be one of the most important environmental problems in the modern world. In areas with high pollution, such as areas near Hg mines, the Hg content in soil and plants is much higher than in other areas. Areas with vegetation can be ranked according to the size of the emissions as follows: forests > other areas (tundra, savannas, and chaparral) > agricultural areas > grassland ecosystems areas of land devoid of vegetation emit more Hg than those with plants. ![]() Generally, the largest amounts of Hg are emitted from tropical regions, followed by the temperate zone, and the lowest levels are from the polar regions. The estimation of Hg emissions from soil and plants, which occur mainly in the Hg 0 form, is very difficult. The deposition of Hg pollutants on the ground with low vegetation is as 3–5 times lower than that in forests. ![]() On the land surface, Hg deposition mainly occurs in the oxidized form (Hg 2+), and its transformations are associated primarily with the oxidation–reduction potential of the environment and the biological and chemical processes of methylation. These forms may be sequestered within terrestrial compartments or emitted back into the atmosphere, and the relative importance of these processes is dependent on the form of Hg, the surface chemistry, and the environmental conditions. Resultsĭifferent forms of atmospheric Hg may be deposited on surfaces by way of wet and dry processes. This publication presents a review of the literature on issues related to mercury pollution of the terrestrial environment: soil and plants and their transformations. Pollution of the terrestrial environment is particularly important as it is a place of human life and food production. Environmental contamination by mercury is and will continue to be a serious risk for human health.
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