Tremor mercury exposure

Mercury (Hg) is a toxic metal—it is one of the so-called heavy metals. Hg is a neurotoxin that causes damage to the central nervous system (CNS), which consists of the brain and associated parts. Hg is active at about 50pg/100mL of blood (500 ppb). Central nervous system damage manifests itself as quarrelsome behavior, headaches, depression, and muscle tremors. The classic example of mercury poisoning is the mad hatter, caused by mercury exposure during the felt-making process. 

Mercury was used to cure the felt used in hats, and workers developed the characteristic signs of mercury vapor toxicity. Acute exposure to high concentrations of mercury vapor causes respiratory distress, which can be fatal. The symptoms of chronic exposure to mercury vapor include personality changes such as excitability, depression, memory loss, fine motor tremor that can become progressively worse, gingivitis, and hallucination. There is some mercury inhalation exposure from dental amalgam, but for most people there are no health-related effects. Metallic mercury is very poorly absorbed from the intestine, thus it is much better to swallow the mercury from a thermometer than inhale it (see chapter on mercury). 

Elemental Mercury Vapor. Although there may be toxic effects to the respiratory system from the inhalation of mercury vapor, the major toxic effect is to the CNS. This is especially true after chronic exposure. There are a variety of symptoms such as muscle tremors, personality changes, delirium, hallucination, and gingivitis. 

Metallic Mercury. A number of studies have reported increases in tremors, muscle fasciculations, myoclonus, or muscle pains after acute (Adams et al. 1983 Bluhm et al. 1992a Karpathios et al. 1991 McFarland and Reigel 1978), intermediate (Aronow et al. 1990 Barber 1978 Sexton et al. 1976 Taueg et al. 1992), or chronic (Albers et al. 1982, 1988 Bidstmp et al. 1951 Chaffin et al. 1973 Chapman et al. 1990 Fawer et al. 1983 Smith et al. 1970 Verberk et al. 1986 Vroom and Greer 1972 Williamson et al. 1982) exposure to metallic mercury vapor. These effects are probably neurally mediated and are discussed more fully in Section 2.2.1.4. 

In contrast with the long-term (perhaps permanent) effects noted in the previous study, Yang et al. (1994) reported that recovery from chronic elemental mercury intoxication may be complete when patients are removed early from the exposure environment. A 29-year-old worker in a Taiwanese lampsocketmanufacturing facility, with an initial urinary mercury concentration of 610 g/L (in a 24-hour sample) and a blood mercury concentration of 237 g/L (reference range, <10 g/L), exhibited a variety of symptoms, including blurred vision, dysarthria, prominent gingivitis, tremors (usually postural and... 

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