Inhalation mercury

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). 

Unithiol and succimer increase urine mercury excretion following acute or chronic elemental mercury inhalation, but the impact of such treatment on clinical outcome is unknown. Dimercaprol has been shown to redistribute mercury to the central nervous system from other tissue sites, and since the brain is a key target organ, dimercaprol should not be used in treatment of exposure to elemental or organic mercury. Limited data suggest that succimer, unithiol, and N- acetyl-L-cysteine (NAC) may enhance body clearance of methylmercury. 

Much inconvenience and injury attend the workmen at this establishment, owing to the dangerous effects of the mercury, inhaled whilst brushing down the walls of the chambers,—an operation which exposes the men to tbe vapors for two hours. lienee, it is no strange occurrence to observe many of the operatives salivated or affected with nervous tremblings. 

Potential sources of human exposure to mercury include food contaminated with mercury, inhalation of mercury vapors in ambient air, and exposure to mercury through water, soil and sediment. Dietary intake is by far the most important source of exposure to mercury for the general population. Fish and other seafood products are the main source of methylmercury in the diet studies have shown that methylmercury concentrations in fish and shellfish are 10-100 times greater than in other foods, including cereals, potatoes, vegetables, fruits, meats, poultry, eggs, and milk. As of December 1998, mercury was the chemical contaminant responsible, at least in part, for the issuance of 1931 fish consumption advisories by 40 states, including the US territory of American Samoa. Almost 68% of all advisories issued in the United States are a result of mercury contamination in fish and shellfish. Advisories for mercury have increased steadily by 115% from 899 advisories in 1993 to 1931 advisories in 1998. The number of states that have issued mercury advisories also has risen steadily from 27 states in 1993 to 40 states in 1997, and remains at 40 states for 1998. Advisories for mercury increased nearly 8% from 1997 (1782 advisories) to 1998 (1931 advisories). 

Table 2-1. Levels of Significant Exposure to Inorganic Mercury - Inhalation... 

Metallic Mercury. Inhalation exposure of individuals to elemental mercury vapors for acute and intermediate durations has resulted in erythematous and pruritic skin rashes (Aronow et al. 1990 Bluhm et al. 1992a Foulds et al. 1987 Karpathios et al. 1991 Schwartz et al. 1992 Sexton et al. 1976). Other dermal reactions to mercury exposure include heavy perspiration (Aronow et al. 1990 Fagala and Wigg 1992 Karpathios et al. 1991 Sexton et al. 1976) and reddened and/or peeling skin on the palms of the hands and soles of the feet (Aronow et al. 1990 Fagala and Wigg 1992 Karpathios et al. 1991). 

Danielsson BRG, Fredriksson A, Dahlgren L, et al. 1993. Behavioral effects of prenatal metallic mercury inhalation exposure in rats. Neurotoxicol Teratology 15 391-396. 

Haddad J, Stenberg E. 1963. Bronchitis due to acute mercury inhalation Report of two cases. Am Rev Respir Dis 88 543-545. 

Kanluen S, Gottlieb CA. 1991. A clinical pathologic study of four adult cases of acute mercury inhalation toxicity. Arch Pathol Lab Med 115(1) 56-60. 

HUMAN TOXICITY DATA (diethyl mercury) inhalation - human LCLo 1040i-ig/mVl4W. 

Mercury inhalation has been linked to Alzheimer disease and autism, and limitation to mercury emissions is currently the subject of legislation by the U.S. Environmental Protection Agency (ERA) who will impose limits on mercury emissions from coal-tired boilers in the utilities industry. Mercury control techniques currently used in the industry include the use of flue-gas desulfurization (EGD) units and, as a result of mercury measurements around these units, it is known that oxidized and not elemental mercury is removed by the EGDs. Consequently, one method to increase mercury removal by this type of unit is to introduce a catalyst to promote the oxidation of mercury. Mercury measurement [128,129] led to the discovery that a gold-coated sand sample in a simulated flue-gas environment absorbed elemental mercury until an equilibrium was established and desorption of oxidized mercury began. Individual components of the simulated flue-gas have been evaluated for their effect on the oxidation of mercury, and it was found that nitrogen dioxide and hydrogen... 

---