Mercury, human effects

Developmental Toxicity. Occupational exposure to metallic mercury in males did not result in statistically significant effects on malformations or the number of children bom (Alcser et al. 1989 Lauwerys et al. 1985). The results from an inhalation developmental rat study (Baranski and Szymczyk 1973) suggest that metallic mercury vapors may cause a higher incidence of fetal malformations, resorptions, and deaths. Dermal studies on metallic mercury in humans and animals were not available. Additional well-conducted inhalation and dermal studies on metallic mercury in animals are needed to evaluate the potential for adverse developmental effects to humans from mercury. 

Hg(II) induced SCEs only slightly in CHO cells but a greater response was seen in human lymphocytes (Howard et al. 1991 Morimoto et al. 1982). Chromosomal aberrations have been induced by Hg(II) and by organomercury compounds in a variety of cells (Leonard et al. 1983 Howard et al. 1991). In addition to its clastogenic effects, mercury compounds cause a disturbance of mitosis due to their reactions with the sulfhydryl groups in the spindle fiber proteins. Deleterious effects on the spindle apparatus were seen with Me-Hg-Cl in a number of studies (Watanabe et al. 1982 Curle et al. 1987). Effects on the spindle apparatus are likely to lead to errors of chromosomal segregation (i.e., aneuploidy) (Ramel and Magnusson 1979 Verschaeve et al. 1984). 

Heavy metals such as mercury, lead, nickel copper and cadmium have been proven to cause serious health effects on human [1], Mercury had been widely used in many fields, such as medical, scientific research applications, and in amalgam material for dental restoration. It is used in lighting electricity passed through mercury vapor in a phosphor tube produces short-wave ultraviolet light which then causes the phosphor to fluoresce, making visible light. 

Air-poUutant effects on neural and sensory functions in humans vary widely. Odorous pollutants cause only minor annoyance yet, if persistent, they can lead to irritation, emotional upset, anorexia, and mental depression. Carbon monoxide can cause death secondary to the depression of the respiratory centers of the central nervous system. Short of death, repeated and prolonged exposure to carbon monoxide can alter sensory protection, temporal perception, and higher mental functions. Lipid-soluble aerosols can enter the body and be absorbed in the lipids of the central nervous system. Once there, their effects may persist long after the initial contact has been removed. Examples of agents of long-term chronic effects are organic phosphate pesticides and aerosols carrying the metals lead, mercury, and cadmium. 

Hazardous air pollutants (HAPs) are substances that may cause immediate or long-term adverse effects on human health. HAPs can be gases, particulates, trace metals such as mercui y, and vapors such as benzene. For coal-fired power plants, the HAPs of most concern are metals such as mercury, arsenic, and vanadium. 

Mercury provides an excellent example of the importance of metal speciation in understanding biogeochemical cycling and the impact of human activities on these cycles. Mercury exists in solid, aqueous, and gaseous phases, and is transported among reservoirs in all these forms. It undergoes precipitation-dissolution, volatilization, complexation, sorption, and biological reactions, all of which alter its mobility and its effect on exposed populations. The effect of all... 

The next eight chapters will be devoted to the ecotoxicology of groups of compounds that have caused concern on account of their real or perceived environmental effects and have been studied both in the laboratory and in the field. These are predominantly compounds produced by humans. However, a few of them, for example, methyl mercury, methyl arsenic, and polycyclic aromatic hydrocarbons (PAHs), are also naturally occurring. In this latter case, there can be difficulty in distinguishing between human and natural sources of harmful chemicals. 

Organoarsenic compounds have been of importance in human toxicology but have not as yet received much attention in regard to environmental effects. Like methyl mercury compounds, they are both synthesized in the environment from inorganic forms and released into the environment as a consequence of human activity (Environmental Health Criteria 18). They can cause neurotoxicity. 

Corti R, Fayad ZA, Fuster V, Worthley SG, Helft G, Chesebro J, Mercuri M, Badimon JJ. Effects of lipid-lowering by simvastatin on human atherosclerotic lesions a longitudinal study by high-resolution, noninvasive magnetic resonance imaging. Circulation 2001 104(3) 249. 

Roulet M, Lucotte M, Farella N, Serique G, Coelho H, Sousa Passes CJ, de Jesus da Silva E, Scavone de Andrade P, Mergler D, Amorim M. 1999. Effects of recent human colonization on the presence of mercury in Amazonian ecosystems. Water Air Soil Pollut 112 297-313. 

Again, the waste treatment scenario with incineration has by far to the highest score for human toxicity. The scores for the other scenarios are more or less the same. The incineration of EoL PVC will lead to toxic emissions of metals (arsenic, lead, chromium, see Table 5) causing human health effects. However, the most important contribution to the human health effect is caused by the emission of mercury in the upchain processes of the production of mercury and sodium hydroxide. Sodium hydroxide is an auxiliary material in the waste incineration process. Mercury... 

Small amounts of some contaminants can be serious. When we burn coal, not only do we produce carbon dioxide, the major product, but we can liberate small amounts of mercury and larger amounts of sulfur dioxide. The mercury can form toxins that harm fish as well as humans, while sulfur dioxide can produce acid rain that destroys forests and water supplies. How can these contaminants be most effectively removed or dealt with And how can we generate the energy that we need without releasing such by-products ... 

Diez S, Barata C, Raldua D (2008) Exposure to mercury a critical assessment of adverse ecological and human health effects. In Prasad MNV (ed) Trace elements as contaminants and nutrients consequences in ecosystems and human health. Wiley, New York, pp 345-373... 

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