Chemicals &

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Heavy Metals

UNEP’s Chemicals Branch undertakes activities in the field of mercury, lead and cadmium aimed at reducing the risk to humans and the environment from these metals and compounds containing them.

Mercury (chemical symbol: Hg) is a naturally occurring element found in air, water, and soil. It is distributed throughout the environment by both natural and anthropogenic (human) processes. Mercury is found in various inorganic and organic forms and is a toxic persistent pollutant that bioaccumulates and biomagnifies through food webs. 

Lead (chemical symbol: Pb) is a heavy metal that is toxic at very low exposure levels and has acute and chronic effects on human health. It is released by various natural and anthropogenic sources into the atmosphere and into aquatic and terrestrial environments. Lead can move in the environment between water, air and soil, which may change the pattern of exposure. Lead is used and traded globally as a metal in various products e.g. batteries, different compounds, lead sheets, ammunition, alloys, cable sheathing and petrol additives.  

Cadmium (chemical symbol: Cd) is a non-essential and toxic element for humans. It is associated with kidney damage. It is used as a pigment, a stabilizer for plastics and as a component of batteries. It is also widely distributed when it is present as a contaminant in fertilizers. 

The integration of sound management of chemicals into national development planning processes to support sustainable development in developing countries and countries with economies in transition was recognized as a priority in SAICM. To support this priority area, UNDP and UNEP have developed a Partnership Initiative for Integration of Sound Management of Chemicals (SMC) into development planning processes to help countries to identify specific areas of chemicals management which are likely to result in concrete environment, health and economic benefits and put in place a plan to begin addressing the identified gaps. It has furthermore the aim to assess their national development strategies relative to protecting the environment and human health from adverse effects through sound management of chemicals, in order to improve where relevant the integration of chemicals management priorities into the national development discourse and planning agenda.