Atmospheric mercury: How much do we really know?

Abstract

Mercury in the environment is of concern because of its toxic effects on humans and other organisms. The introduction of mercury into the environment from anthropogenic sources coupled with natural sources has compelled governments on national and international levels to address the need for its control. Regulations have been directed at mercury emitting industries such as power generation plants that consume fossil fuels, smelters, incinerators, chlor-alkali industries, and many others. However, mercury continues to be found in fish at levels of a few mg/kg. Elevated levels of mercury have also been found in air and water samples in regions far from industrial or other man-made sources. Despite mercury's importance and history, its environmental mass balance is uncertain, its long range atmospheric transport and fate are not fully understood, and its collection and measurement continues to be difficult.