The Sunday Mail
Mercury is an element that is found all over the earth, in soil, rocks, and water. Even trace amounts can be found in the air. The largest deposits on earth are as cinnabar (mercuric sulfide). Mercury exists in several forms such as a liquid metal (quicksilver), as a vapour, and in compounds (organic and inorganic). Scientifically, the symbol for mercury is Hg and its element number is 80.
Mercury has been used for centuries as a medicine, to make amalgams, and in many industrial applications. Eventually, scientists, physicians and others realised the various forms of mercury caused health problems.
The phrase “Mad as a Hatter” originated in the 1800s from the observation that people (hatters) who used mercury to process felt for hats often developed mental changes.
The problem with mercury is that if humans are exposed to any of the forms of mercury, depending on the amount (dose), route (ingestion, skin contact, inhalation), and duration (time) of exposure, mercury can be toxic to them.
Some elemental and chemical forms of mercury (vapour, methylmercury, inorganic mercury) are more toxic than other forms. The human foetus and medically compromised people (for example, patients with lung or kidney problems) are the most susceptible to the toxic effects of mercury.
Although various forms of mercury can cause some different symptoms, the effects that are most toxic occur in the brain and nervous system.
There are numerous items that contain mercury in its various forms that can cause a toxic exposure. They are present in many workplaces and in the home. For example, coal burning power plants emit mercury (the highest source of mercury put into the air), home thermometers, “button” batteries, the new energy-saving fluorescent light bulbs, and seafood (shellfish, tuna, marlin and many others).
Such items are all potential sources of mercury poisoning. However, guidelines are available for the prudent use, consumption and disposal of items containing forms of mercury.
Human activities that release mercury into the environment include the burning of coal and mining of gold.
Symptoms of mercury poisoning can be numerous and may occur either rapidly or over long periods of time. In general, symptoms occur and progress more rapidly the higher the dose of mercury encountered. Exposure to the various forms of mercury can result in some similar and some different symptoms.
Symptoms can be grouped into three categories based on the form of mercury toxicity: 1) elemental and vapourised mercury, 2) organic mercury, and 3) inorganic mercury.
Elemental and vapourised mercury poisoning symptoms
Elemental mercury toxicity (which usually occurs in the vapourised form) can cause:
◆ mood swings, nervousness, irritability, and other emotional changes,
◆ insomnia,
◆ headache,
◆ abnormal sensations,
◆ muscle twitching,
◆ tremors,
◆ weakness,
◆ muscle atrophy, and
◆ decreased cognitive functions.
High exposures of elemental mercury can cause kidney malfunction, respiratory failure, and death.
Organic mercury poisoning symptoms
Organic mercury toxicity (most frequently in the methylmercury form from ingestion), causes neurological malfunctions, and especially in a foetus, impaired neurological development. Other symptoms include:
◆ peripheral vision impairment,
◆ stinging or needle-like sensations in the extremities and mouth,
◆ loss of co-ordination,
◆ muscle weakness, and
◆ other impairments of speech and hearing.
Since many pregnant women have had methylmercury toxicity, the effects of this toxicity on their children was studied. Importantly, the foetal brain was shown to be very sensitive to methylmercury, developmental impairments such as reduced ability in thinking, attention span, memory, and most motor skills occurred in various degrees, often severe, even if the mother developed few if any symptoms.
Inorganic mercury poisoning symptoms
Inorganic mercury toxicity often causes skin rashes and inflammation (dermatitis). If ingested, it can dissolve tissues and some may be absorbed by the intestinal tissue. Large amounts of ingested inorganic mercury may cause bloody diarrhoea. Absorbed mercury can spread to other organ systems resulting in mental changes including mood swings and memory loss or renal damage. Muscle weakness may also occur.
Other mercury poisoning symptoms
Many other symptoms and health problems have been attributed to mercury poisoning (for example, high blood pressure, endometriosis, headaches) in anecdotal reports in the popular press and in a few case reports in scientific publications.
Currently, there are no good studies to support these claims, however, if people have concerns about their symptoms and health problems related to mercury exposure, they should discuss their concerns with their doctor. — emedicinehealth.com
