Visualizations : Natural and anthropogenic (human-caused) emissions sources of mercury : Global Mercury Emissions are approximately 7000...

Global Mercury Emissions are approximately 7000 tons per year

Natural sources of mercury—such as volcanic eruptions and emissions from the ocean—have been estimated to contribute about a third of current worldwide mercury air emissions, whereas anthropogenic (human-caused) emissions account for the remaining two-thirds. These estimates are highly uncertain. Much of the mercury circulating through today’s environment is mercury that was released years ago, when mercury was commonly used in many industrial, commercial, and residential products and processes. Land and water surfaces can repeatedly re-emit mercury into the atmosphere after its initial release into the environment. The pie chart below shows that anthropogenic emissions are roughly split between these re-emitted emissions from previous human activity, and direct emissions from current human activity.

http://www.epa.gov/mercury/control_emissions/global.htm
http://www.undeerc.org/catm/pdf/PavlishMercury2006SpecialSessionSlides.pdf