Mercury is recognized as a chemical of global concern due to its long-range transport in the atmosphere, its persistence in the environment, its ability to bioaccumulate in ecosystems and its significant negative effect on human health and the environment.  

Mercury can produce a range of adverse human health effects, including permanent damage to the nervous system, in particular the developing nervous system.  Due to these effects, and also because mercury can be transferred from a mother to her unborn child, infants, children and women of child bearing age are considered vulnerable populations.

UNEP has been working to address mercury issues since 2003.  Currently, the UNEP mercury programme has two main facets.