Mercury human health

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. 

A number of environmental issues have received widespread publicity (Table 7.1), from major accidents at plants (e.g., Seveso and Bhopal) to the global and regional impacts associated with energy utilization (e.g., carbon dioxide, acid rain, and photochemical oxidants), the improper disposal of chemical waste (e.g., Love Canal and Times Beach), and chemicals that have dispersed and bioaccumulated affecting wildlife (e.g., PCBs and DDT) and human health (e.g., cadmium, mercury, and asbestos). 

Elemental mercury and inorganic mercury compounds human health aspects (No. 50, 2003) Ethylenediamine (No. 15, 1999)... 

Wildlife toxicologists should be attuned to developments in human health mercury, as assays that have been used successfully on humans may be suitable or adaptable for other vertebrate species. Echeverria and co-workers (Echeverria et al. 2005, 2006 Heyer et al. 2006) have characterized a gene encoding coproporphyrinogen oxidase, a gene in the heme biosynthetic pathway. Polymorphism in this gene predicts differential response to elemental mercury exposure in human subjects. Plans to modify this assay for other mercury species in matrices from wildlife are under way. 

Because many batteries contain toxic constituents such as mercury and cadmium, they pose a potential threat to human health and the environment when improperly disposed. Although batteries generally make up only a tiny portion of MSW, <1%, they account for a disproportionate amount of the toxic heavy metals in MSW. For example, the U.S. EPA has reported that, as of 1995, nickel-cadmium batteries accounted for 75% of the cadmium found in MSW. When MSW is incinerated or disposed of in landfills, under certain improper management scenarios, these toxics can be released into the environment. 

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... 

Holmes P, James KAF, Levy LS (2009) Is low-level environmental mercury exposure of concern to human health Sci Total Environ 408 171-182... 

Exposure to Hg may cause serious harm to human health, at high doses it can even be fatal. Mercury toxicity usually involves the kidneys and/or nervous system disorders (central nervous system and neurobehavioral changes). Mercury contamination has been found in more than 70 federal sites with Hg-contaminated wastes. 

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... 

Proposed mercury criteria for protection of various resources and human health... 

Data from National Academy of Sciences (NAS). 1978. An Assessment of Mercury in the Environment. Natl. Acad. Sci., Washington, D.C. 185 pp. Clarkson, T.W., R. Hamada, and L. Amin-Zaki. 1984. Mercury. Pages 285-309 in J.O. Nriagu (ed.). Changing Metal Cycles and Human Health. Springer-Verlag, Berlin. 

Proposed mercury criteria for the protection of sensitive aquatic organisms, birds, and mammals, as well as human health, are shown in Table 5.11. In almost every instance, these criteria are listed as concentrations of total mercury, with most, if not all, the mercury present as an organomercury species. In some cases the recommended criteria are routinely exceeded, as is the case for brown bears (Ursus arctos) in the Slovak Republic (Zilincar et al. 1992), and in Italian seafood products recommended for human consumption (Barghigiani and De Ranieri 1992). 

Table 5.11 Proposed Mercury Criteria for Protection of Various Resources and Human Health Resource and Criterion (units in parentheses) Mercury Concentration Reference11...

O Research the environmental impact of mercury pollution. Describe the main sources of mercury in the environment, the effects of mercury on human health, and at least one incident in which humans were harmed by mercury pollution. 

O2 concentrations, such as found in marine wetlands. High biomethylation rates have also been observed in coastal sediments. Because methylmercury is transferred up the food chain, the marine fish that occupy high trophic levels have very high mercury concentrations. In some cases, such as for tuna and swordfish, concentrations are high enough to pose human health risks. 

Fungicides have caused a number of human health disasters. In the late 1950s, approximately 4000 people in Turkey were poisoned by hexachlorobenzene that had been applied to seed grain to protect against soil fungus. Adults and particularly children developed diseases of the skin and bone. In Iraq, a similar incident occurred when people consumed grain coated with a mercury compound. 

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