Mercury is a naturally occurring element and there are thus many natural sources of mercury. Mercury is contained in many minerals, such as those used to produce non-ferrous metals, and in fossil fuels. Human activity has increased the mobilization of mercury into the environment, raising the amounts in air, soils, fresh-water, oceans and biota.

Pure mercury is liquid at room temperature but evaporates easily.

Mercury and Environment

As mercury is an element, it cannot be broken down into harmless substances or be destroyed. Once it has entered the environment it persists and only changes form, cycling between air, land and water until it is eventually removed from the system through burial in deep ocean sediments or lake sediments.

Mercury and Human Health

Mercury can seriously harm human health in several ways. The first Global Mercury Assessment report, published by UNEP in 2002 with the input from Governments, IGOs and NGOs, and the private sector, showed that mercury is highly toxic, with adverse impacts to human health and the environment.

Mercury can be absorbed by inhalation, direct contact with the skin or by ingestion of contaminated food and water. It can cause adverse effects in the nervous system, affecting neurological, cognitive, and motor functions.
There are some populations that are especially susceptible to the adverse effects of mercury, most notably fetuses and young children. Mercury absorbed in the body of a pregnant woman can also have effects on the fetus.

Natural sources
These releases occur due to the natural mobilization of mercury naturally occurring in the Earth’s crust, such as volcanic activity and weathering of rocks.

Anthropogenic Sources

Human-generated releases, such as:

– Mobilization of mercury impurities in raw materials

– Intentional use of mercury in products and processes

– Re-mobilization of previous anthropogenic mercury releases