What is Mercury?

Molecule Ring MercuryMercury is a neurotoxin.

Mercury is a naturally-occurring chemical element found in rock in the earth’s crust, including in deposits of coal.  On the periodic table, it has the symbol “Hg” and its atomic number is 80. It exists in several forms:
  • elemental (metallic) mercury,
  • inorganic mercury compounds, and
  • methylmercury and other organic compounds.


In terms of occupational exposure to mercury, spills of even small amounts of the element can see mercury vapour contaminating the indoor air, and there have been numerous reported cases of deaths being attributed to small spillages that were not properly cleaned up.

Ensuring that facilities are safe as they are worked upon and that there is no health risk associated with any repurposed land or with new or refurbished buildings when they are occupied places an emphasis on effective mercury contamination monitoring. 


Health Issues

Health issues affected by exposure to mercury depends on a number of factors:

  • the form of mercury (for example, methylmercury or elemental (metallic) mercury);
  • the amount of mercury in the exposure;
  • the age of the person exposed (unborn infants are the most vulnerable);
  • how long the exposure lasts;
  • how the person is exposed — breathing, eating, skin contact, etc.; and
  • the health of the person exposed.

– United States Environmental Protection Agency

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