The Clean Air Act, as amended in 1990, required the U.S. EPA to prepare an assessment of the magnitude of U.S. mercury emissions by source, the health and environmental effects of the emissions, and the cost and availability of control technologies. This report identified mercury as a human health and environmental problem needing additional scientific and technical research.
Fish consumption is known to be the dominant pathway for exposure of humans and wildlife to mercury.
It is also accepted that the majority of this mercury comes from atmospheric deposition. This strategy guides ORD s mercury research program through 2005. An integral part of the strategy involves study of atmospheric mercury transport, transformation, and fate. Mercury is a naturally occurring element that cycles between the atmosphere, land, and water. Atmospheric mercury exists mostly in elemental gas form, but a variety of oxidized mercury compounds also occur.