Mercury is a chemical element which means that it can’t be created or destroyed. In its pure form, elemental mercury is a shiny silver liquid which is how it came to be known as quicksilver. Mercury has been widely used in a variety of products due to its unique properties. It is the only metal that is liquid at room temperature and a good conductor of electricity. These qualities made mercury a popular choice for household, commercial, medical and industrial applications, though its use has been phased out of most modern products.
Mercury occurs naturally in the environment, but human activities like fossil fuel combustion, gold mining and the improper disposal of mercury-containing products has accelerated mercury emissions. Since the start of the Industrial Revolution, mercury in the surface waters of our oceans has more than tripled. This is unfortunate because mercury is a threat to human and ecosystem health.
Approximately half of the mercury in the environment originates from natural sources and processes; the other half is from human activities.
– Environment Canada
Exposure to mercury – even small amounts – may cause serious health problems. It has toxic effects on the nervous, digestive and immune systems, and on lungs, kidneys, skin and eyes. Mercury poses a threat to the development of a child in utero and early in life so pregnant women and children should always be kept away from any spill. Long-term exposure can worsen symptoms and lead to personality changes, stupor, and in extreme cases, coma or death.
When atmospheric mercury falls to earth, it may be altered by bacterial or chemical processes into an organic form known as methylmercury. Methylmercury is more toxic than elemental mercury and it has the ability to migrate through cell membranes, “bioaccumulate” in living tissue and ultimately travel up the food chain. Mercury is potent stuff: just one gram of mercury can contaminate an eight-hectare lake to the point where the fish are inedible for a full year.