Mercury natural resources

Cadmium (Cd) anode cells are at present manufactured based on nickel-cadmium, silver-cadmium, and mercury-cadmium couples. Thus wastewater streams from cadmium-based battery industries carry toxic metals cadmium, nickel, silver, and mercury, of which Cd is regarded the most hazardous. It is estimated that globally, manufacturing activities add about 3-10 times more Cd to the atmosphere than from natural resources such as forest fire and volcanic emissions. As a matter of fact, some studies have shown that NiCd batteries contribute almost 80% of cadmium to the environment,4,23 while the atmosphere is contaminated when cadmium is smelted and released as vapor into the atmosphere4 Consequently, terrestrial, aquatic, and atmospheric environments become contaminated with cadmium and remain reservoirs for human cadmium poisoning. 

Partly because of this concern, the Wisconsin Department of Natural Resources, in cooperation with the Electric Power Research Institute, initiated an extensive study of Hg cycling in seepage lakes of north-central Wisconsin (14). The mercury in temperate lakes (MTL) study used clean sampling and subnanogram analytical techniques for trace metals (10, 17) to quantify Hg in various lake compartments (gaseous phase, dissolved lake water, seston, sediment, and biota) and to estimate major Hg fluxes (atmospheric inputs, volatilization, incorporation into seston, sedimentation, and sediment release) in seven seepage lake systems. 

Chevalier, P. Mercury. Canadian Minerals Yearbook 1999. Natural Resources Canada. 2000. 

Vermont Senate Natural Resources and Energy Committee, proposed mercury legislation (Senate Bill 91) as passed by the Vermont Senate Natural Resources and Energy Committee on March 21, 2001. Available at http //www.mercvt.org/s91final.htm (accessed September 2004). 

The concentrations of pollutants in air and water are also measured as ppm. If these concentrations exceed a fixed value, they may be considered hazardous. For instance, when the concentration of mercury in drinking water reaches 0.5 ppm, this level is regarded as harmful to health. That level refers to 0.5 g in 1000 kg of water. Lead is also dangerous at a certain level. 0.250 ppm lead can cause delayed cognitive development in children. Carbon monoxide is a significant factor in air pollution. 750 ppm of carbon monoxide by volume in the air we inhale is considered to be lethal. All these examples show that the relationship of the human body to the ecological system is very finely balanced. Even a small increase in concentrations of pollutants may result in dire consequences. Therefore, scientists have been working on the problem of pollution in order to help maintain the relative purity of our vital natural resources. 

United States Geological Service (U.S.G.S.). U.S. Geological Survey, Mineral Commodity Summaries (Mercury). 1999. Chevalier, P. Mercury. Canadian Minerals Yearbook 1999. Natural Resources Canada. 2000. 

The ASTM F 1185 designation specifies chemical and crystallographic requirements for hydroxyapatite applied to the surfaces of surgical implants. Elemental analyses for calcium and phosphorus will confirm the expected stoichiometry of hydroxyapatite. The calcium and phosphorus contents will be determined by a suitable method such as ion chromatography. A quantitative X-ray diffraction analysis will determine a hydroxyapatite content of at least 95%. The concentration of deleterious trace elements such as arsenic, cadmium, mercury and lead will be assessed for hydroxyapatite derived from natural resources. The analysis of other trace elements may be required, based on the conditions, apparatus or environments specific to the manufacturing techniques and raw materials. Inductively coupled plasma/mass spectroscopy (ICP/MS), atomic absorption (AAS) or the... 

Mercury-sensitive ecosystems are those where comparatively small inputs or inventories of total mercury, i.e., 1.0-10.0 g Hg/ha, result in elevated concentrations of methylmercury in natural resources these systems are characterized by efficient conversion of inorganic mercuric mercury to methylmercury sufficient to contaminate aquatic and wildlife food webs. Known sensitive ecosystems include surface waters adjoining wetlands, low alkalinity or low pH lakes, wetlands, and flooded terrestrial areas. 

Proposed Mercury Criteria for the Protection of Natural Resources and Human Health... 

Table 19.1. Proposed mercury criteria for the protection of selected natural resources.

At this point, it seems that four courses of action are warranted for protection of human health and sensitive natural resources. First, toxic mercurials in agriculture and industry should be replaced with less toxic substitutes. In Sweden, for example, clinical mercury thermometers have been prohibited since January 1,1992, for import, manufacture, and sales. Since January 1993, the same prohibition was applied to other measuring instruments and electrical components containing mercury. Since 2000, Sweden has prohibited mercury in all processes and products, including thermometers and sphygmomanometers, and replaced them with available substitutes. 

Marine oils form a significant proportion (2-3%) of the world s available edible oils. Future trends are difficult to predict but unless we learn to fish the sea in a controlled way this natural resource will almost certainly decline. An additional danger arises from pollution. In isolated cases this has reached a point where the fish have become inedible, e.g. mercury poisoning in Japan (Wood, 1976). 

The input of mercury into the environment is mainly caused by volcanic activities, burning coal, using mercury in industry and agriculture and through handling of waste. The total amount of mercury entering the atmosphere is estimated at 150 000 tons per year. About two-thirds of this amount comes from natural resources. 

To the Moscow electroanalysts belonged also Yevgeniy Yanovich Neyman (Fig. 5.6.6), who much too early passed away. Part of his legacy are two remarkable books pubhshed written and pubhshed by Kh yena Zalmanovna Brainina together with him [198,199]. In 1968 Neyman has defended his PhD thesis dedicated to the determination of mercury on a graphite electrode. He worked in a special laboratory of a central institute of the Ministry of Natural Resources ( Minprirody in Russian). In 1978 he has defended his doctor of science thesis entitled Inverse... 

Deposits. Selenium forms natural compounds with 16 other elements. It is a main constituent of 39 mineral species and a minor component of 37 others, chiefly sulfides. The minerals are finely disseminated and do not form a selenium ore. Because there are no deposits that can be worked for selenium recovery alone, there are no mine reserves. Nevertheless, the 1995 world reserves, chiefly in nonferrous metals sulfide deposits, are ca 70,000 metric tons and total resources are ca 130,000 t (24). The principal resources of the world are in the base metal sulfide deposits that are mined primarily for copper, zinc, nickel, and silver, and to a lesser extent, lead and mercury, where selenium recovery is secondary. 

Third, continued periodic monitoring of fishery and wildlife resources is important, especially in areas with potential for reservoir development, in light of the hypothesis that increased flooding increases the availability of mercury to biota. The use of museum collections for mercury analysis is strongly recommended for monitoring purposes. For example, the Environmental Specimen Bank at the Swedish Museum of Natural History constitutes a base for ecotoxicological research and for spatial and trend monitoring of mercury and other contaminants in Swedish fauna (Odsjo et al. 1997). 

One of the most important problems in oceanography and water resources science is the effect of the concentrations and concentration changes of trace metal ions on the nature of the water system (1-6). Recently, there has been much interest in the apparent increased concentration of metal ions such as mercury, lead, and iron. This concern is, at best, speculative since there are insuflBcient analytical techniques to establish baseline normal concentrations with the precision expected of good analytical methods. For example, there has been tremendous publicity concerning the level of mercury concentrations in edible fish in Lake St. Clair (7, 8, 9). Even in extreme cases, there was considerable disagreement in the true mercury concentrations in the fish analyzed. Rottschafer, Jones, and Mark (9) conducted a comparative study in which a homogenous sample of Coho salmon flesh was dis-... 

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