Mercury poisoning can result from exposure to mercury. Mercury occurs naturally in air, water, and soil. It cannot be created artificially. In science, the symbol for mercury is Hg and it has an element number of 80.
Mercury was used for centuries in medicine until it became apparent that it caused health problems. The expression mad as a hatter arose in the 1800s because people who used mercury on felt in hats were often subject to mental changes.
Where Mercury is Found
Mercury is a liquid metal also known as quicksilver which has traditionally been used in light bulbs, thermometers, and switches. Mercury occurs in many rocks, which will release mercury when burned. In the United States, coal-burning electrical plants are the greatest source of mercury emissions in the air which is caused by humans, accounting for more than 40 percent of the total.
Mercury in air settles on water and if it settles on land it enters water. Some microorganisms can change mercury to methylmercury, which is highly toxic and builds up in fish and animals which eat fish. High levels of methylmercury in unborn babies and young children can damage their nervous systems and brains. The EPA gives advice to pregnant women and nursing mothers as to how much fish they should consume.
Exposure to high levels of mercury can damage the brain, heart, kidneys, lungs, and immune system of people of any age. The EPA issues regulations requiring industry to reduce the release of mercury and to correctly dispose of mercury waste. It works alongside industry to encourage voluntary reductions in the use and release of mercury. It works with international organizations to reduce the release of mercury in other countries. The public could assist with mercury reduction by purchasing products which are free of mercury and properly disposing of products which contain it.
The severity of health effects due to mercury exposure vary with the chemical form of the mercury, the dose, the age of the person exposed (fetuses are most susceptible), the duration of exposure, the route of exposure, and the health of the person exposed.
Symptoms of Mercury Poisoning
The symptoms of methylmercury poisoning are impairment of peripheral vision, pins and needles sensations which are usually in the hands and feet and around the mouth, a lack a coordination in movement, impairment of speech, hearing and walking, and muscle weakness. Metallic mercury can cause tremors, emotional changes, insomnia, neuromuscular changes such as weakness and twitching, headaches, disturbances to sensations, and impairment of cognitive function. Exposure to higher amounts can cause kidney damage, respiratory failure, and death. Exposure to inorganic mercury can lead to skin rashes, memory loss, mood swings, muscle weakness, and mental disturbance.
How Mercury Poisoning Can Occur
Industrial effluent containing methylmercury which was released into Minimata Bay in Japan caused more than 1,700 fatalities. Mercury has sometimes been used in skin creams, most recently in 1996 in a cream from Mexico by the name of Crèma de Belleza-Manning. Mercury poisoning can occur if products including valves, medical equipment, and thermometers are broken.
If a person knows or suspects that they have been exposed to mercury, they should seek immediate medical attention. Early treatment can prevent or lessen the adverse effects of mercury poisoning.