Mercury is released from the fillings partly as an elemental mercury vapor and partly as corrosion products and amalgam particles. Chewing accelerates this process. Subjects of the study were not permitted to eat fish and other seafood before or during the study because of the risk of mercury exposure. The most common, but usually not the first, sign of chronic mercurial poisoning is tremor or symptoms similar to multiple sclerosis. This may occur in the eyelids but is observed most frequently in the fingers and later in the arms and legs.
Sever cases can develop rigidity.
An effect on handwriting because of the intention tremor has been a frequent observation. Neuralgia, paresthesia, ataxia, exaggerated knee jerks, and altered plantar reflexes have been reported. Studies have linked mercury exposure from the environment with a number and variety of illnesses including allergies, chronic fatigue, depression, GI disorders, immune system suppression, periodontal disease, neurological problems, reproductive disorders, birth defects, kidney disease, heart problems, hypertension, respiratory disorders and skin disease. Mercury can interfere with any process or organ in the body, since it is poisonous to all cells, but it has a marked effect on the immune system. If a person has a chronic health problem for which a cause has not been found and mercury fillings are present in the mouth, mercury toxicity may be a contributing factor.