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Mercury Poisoning


These symptoms in Alphabetical order include:

Arthritis-like joint pain
Amyotrophic Lateral Sclerosis { ALS - "Lou Gehrig's Disease" }
Antibiotic Resistance
Abnormal Hunger
Alzheimer's Disease
Anorexia Nervosa
Birth Defects
Cerebral Palsy
Chronic Fatigue
Crohn's Disease
Diabetes Insipidus-like symptoms
Hypersensitivity] {also -mercury hypersensitivity }
Graves Disease-like symptoms
Hearing disturbances
Heart Attacks
Immune system imbalances
Migraine Headaches
MS {multiple sclerosis}-like symptoms
Oral Diseases
Vision Disturbances


Mercury (Hg) is an odorless silvery metal liquid which is insoluble in water but dissolves in nitric acid and sulphur. It has a MW of 200.59 and an At.No. of 80. It is heavier than lead (Pb) which has a density of 11.36 while mercury has a density of 13.59. Gold has a density of 19.32 and is heavier than both of them. The BP of mercury is 356.72 deg C and the FP is - 38.87 deg C.


Mercury is a naturally occurring metal which has several forms. The metallic mercury is a shiny, silver-white, odorless liquid at room temperature. A common name for mercury is quicksilver. If heated, it is a colorless, odorless gas.
Mercury combines with other elements, such as chlorine, sulfur, or oxygen, to form inorganic mercury compounds or "salts," which are usually white powders or crystals.Compounds containing mercury are poisonous.
Mercury also combines with carbon to make organic mercury compounds. The most common one, methylmercury, is produced when mercury reacts with with bacteria in water,sediment, soil or plants.
Mercury is not found free in nature but is obtained from the mineral cinnabar (HgS). Mercury has long been known to the ancient world and been found in very old Egyptian tombs.
Mercury also comes from natural sources such as volcanic eruptions, fosil burning and municipal waste inceneration. These activities cause tons of mercury to be released into the air and washed by rainfall into rivers and oceans where it is transformed into methylmercury by bacteria.


Mercury is used in dental amalgam, explosive detonators, weapons, laboratory equipment, batteries and electrodes. (calomel pH reference etc. and HMDE in Polarography). It is also used in pesticides-insecticides and in the paper industry. However, the use of fungicides, pesticides and dental amalgam have declined due to health and environmental concerns, but the residue may still persist after past use. Mercury salts are used in skin-lightening creams and in antiseptic ointments. Methylmercury is used in fluorescent lightening, batteries and polyvinyl chloride.

Health Effects

To emphasize, mercury poisoning affects the eye, skin, liver, lungs, kidney and heart. The vapors coming from mercury metal and methylmercury are more potent than other forms in causing damage to brain and central nervous system. Cerebral palsy-like symptoms involves movement and co-ordination problems and complications.
Exposure to high levels of metallic, inorganic, or organic mercury can permanently damage the brain, kidneys, and developing fetus.
Effects on brain functioning may result in irritability, shyness, tremors, changes in vision or hearing, and memory problems.
Short-term exposure to high levels of metallic mercury vapors may cause effects including lung damage, nausea, vomiting, diarrhea, increases in blood pressure or heart rate, skin rashes, and eye irritation.
There are inadequate human cancer data available for all forms of mercury.
Mercuric chloride has caused increases in several types of tumors in rats and mice, while methylmercury increased kidney tumors in male mice.
The EPA has determined that mercuric chloride and methyl mercury are possible human carcinogens.

Methylmercury Poisonng

Methylmercury is the most poisonous form of mercury that can debilitate the human body and cause death. Methylmercury is produced by methylation of inorganic mercury in aquatic biota in both freshwater and ocean sediments. It then accumulates in micro-organisms and fish in the water and is concentrated up the food chain reaching high levels in edible fish. Consuming the contaminated fish is the major cause of mercury poisoning.
Symptoms occur progressively from mild to moderate to advanced, and can be fatal one month after acute exposure.First signs are a decrease in sense of touch, hearing, vision and taste.(metallic taste, salivation). This leads to co-ordination difficulties, hearing loss and auditory problems.(aneroxia, paresthesis,immune suppression). Finally, nervous breakdowm, tremots and incordination. renal failure and lung damage. (manic behavior). High doses may result in death in about four weeks after initial set of symptoms.
Reference can be made to the Minamata catastrophe in Japan (1950's) where thousands of persons died from methylmercury poisoning by eating contaminated fish due to mercury discharges being dumped into the surrounding sea. Thousands also died in Iraq in the 1970's by eating bread made with mercury polluted grain.

Effect on children

Very young children are more sensitive to mercury than adults.
Mercury in the mother's body passes to the fetus and can pass to a nursing infant through breast milk.
However, the benefits of breast feeding may be greater than the possible adverse effects of mercury in breast milk.
Mercury's harmful effects that may be passed from the mother to the developing fetus include brain damage, mental retardation, and incoordination, blindness, seizures, and an inability to speak. Children poisoned by mercury may develop problems of their nervous and digestive systems and kidney damage.


Exposure to mercury occurs from breathing contaminated air, ingesting contaminated water and food, and having dental and medical treatments. Mercury, at high levels, may damage the brain, kidneys, and developing fetus.
Eating fish or shellfish contaminated with methylmercury.
Breathing vapors in air from spills, incinerators, and industries that burn mercury-containing fuels.
Release of mercury from dental work and medical treatments.
Breathing contaminated workplace air or skin contact during use in the workplace (dental, health services, chemical, and other industries that use mercury).
Practicing rituals that include mercury.

Risk of exposure to mercury

Carefully handle and dispose of products that contain mercury, such as thermometers or fluorescent light bulbs.
Do not vacuum up spilled mercury, because it will vaporize and increase exposure.
Teach children not to play with shiny, silver liquids.
Properly dispose of older medicines that contain mercury.
Keep all mercury-containing medicines away from children.
Pregnant women and children should keep away from rooms where liquid mercury has been used.
Mercury spills

Exposure Tests

Tests are available to measure mercury levels in the body.
Blood or urine samples are used to test for exposure to metallic mercury and to inorganic forms of mercury.
Mercury in whole blood or in scalp hair is measured to determine exposure to methylmercury.
Your doctor can take samples and send them to a testing laboratory.
The EPA has set a limit of 2 parts of mercury per billion parts of drinking water (2 ppb).
The Food and Drug Administration (FDA) has set a maximum permissible level of 1 part of methylmercury in a million parts of seafood (1 ppm).
The Occupational Safety and Health Administration (OSHA) has set limits of 0.1 milligram of organic mercury per cubic meter of workplace air (0.1 mg/m) and 0.05 mg/m of metallic mercury vapor for 8-hour shifts and 40-hour work weeks.

Animal testing is sometimes necessary to find out how toxic substances might harm people and how to treat people who have been exposed. Laws today protect the welfare of research animals and scientists must follow strict guidelines.

Rederences :

1. Agency for Toxic Substances and Disease Registry (ATSDR). 1999. Public Health Service.
2. "Mercury Free", by Dr. James Hardy.
3. British Medical Bulletin:familywellnesshq/

Signature: Dhanlal De Lloyd, Chem. Dept, The University of The West Indies, St. Augustine campus
The Republic of Trinidad and Tobago.
Copyright: delloyd2000© All rights reserved.