Heavy metals mercury

Drasch G, Wanghofer E, Roider G. 1997. Are blood, urine, hair, and muscle valid biomonitors for the internal burden of men with the heavy metals mercury, lead and cadmium Trace Elements and Electrolytes 14(3) 116-123. 

Krishnaja, A.P. and M.S. Rege. 1982. Induction of chromosomal aberrations in fish Boleophthalmus dussumieri after exposure in vivo to mitomycin C and heavy metals mercury, selenium and chromium. Mutat. Res. 102 71-82. 

Solution B Heavy metals mercury, lead, cadmium, etc. 

According to the developer, the TDU removes volatile organic compounds and volatile metals from soil. The technology is designed to treat material contaminated with polychlorinated biphenyls (RGBs), polynuclear aromatic hydrocarbons (PAHs), dioxins, and volatile heavy metals (mercury). 

Until that time the main treatment for syphilis had been a prolonged treatment with the highly toxic and cumulative heavy metal mercury— one night with Venus and a lifetime with Mercury . 

The reaction commences at a temperature above 400° C., before the melting temperature is reached, and the fused product therefore always contains some arsenious oxide.1 When heated in hydrogen, the pentoxide is reduced first to arsenious oxide and then to free arsenic. Similar reduction occurs when it is heated with carbon or phosphorus with sulphur, arsenious sulphide is formed. Arsenic and metallic arsenides result when the pentoxide is heated with alkali metals,2 zinc, lead, iron or most other heavy metals mercury and silver react only at high temperature gold and platinum do not react. 

The detection of contamination with mercury is a very serious issue due to the extreme toxicity and ease of reaction of this heavy metal. Mercury is commonly used in many everyday applications, such as thermometry, barometry or scientific apparatus. Therefore, it is important to note the development of a fluorescent IIP membrane for detection of mercury [63], This membrane was based on the combination of two fluorescent functional monomers, namely 4-vinyl pyridine and 9-vinylcarbazole. Binding of Hg2+ was proposed to be based on complexation of the metal ion with lone pairs of both pyridine and carbazole. The IIP membrane was capable of recognizing Hg2+in the linear range of concentrations from 5 x 10 7 to 1 x 10 4 M. Selectivity of the chemosensor was studied for a wide group of possible competitive ions and the chemosensor responded to all of them in the presence of a fixed amount of Hg2+ at 1 x 10 5 M. Nevertheless, the highest influence on recognition properties was observed in the presence of Cu2+ (4.87%) and Pb2+ (4.57%), which are still acceptable values for the successful detection of Hg2+. This progress stimulates further development of the MIP detection of ions. 

The CONEG legislation, which began to take effect in the early 1990s, has to do specifically with packaging materials. An acronym for Coalition of Northeastern Governors, CONEG prohibits the intentional addition of four heavy metals (mercury, lead, cadmium, and hexavalent chromium) into these materials at any level and sets the maximum incidental combined quantities for these metals as follows ... 

Mercury is a rare element in the Earth s crust, It is only relatively concentrated in some volcanic areas and in mineral deposits as a trace constituent of ores of other heavy metals. Mercury concentrations in groundwater and surface waters rarely exceed 1 pg/L. 

Mercury and all of its compounds are extremely poisonous, and mercury is one of the few substances known to have no natural function in the human body. Classified as a heavy metal, mercury is difficult for the body to... 

Mercury is one of a number of toxic heavy metals that occur in trace amounts in fossil fuels, particularly coal, and are also present in waste materials. During the combustion of fuels or wastes in power plants and utility boilers, these metals can be released to the atmosphere unless remedial action is taken. Emissions from municipal waste incinerators can substantially add to the environmental audit of heavy metals, since domestic and industrial waste often contains many sources of heavy metals. Mercury vapor is particularly difficult to capture from combustion gas streams due to its volatility. Some processes under study for the removal of mercury from flue gas streams are based upon the injection of finely ground activated carbon. The efficiency of mercury sorption depends upon the mercury speciation and the gas temperature. The capture of elemental mercury can be enhanced by impregnating the activated carbon with sulfur, with the formation of less volatile mercuric sulfide [37] this technique has been applied to the removal of mercury from natural gas streams. One of the principal difficulties in removing Hg from flue gas streams is that the extent of adsorption is very low at the temperatures typically encountered, and it is often impractical to consider cooling these large volumes of gas. 

Cases of adulteration with the heavy metals mercury (151) and lead (152) have been reported. 

Wetterhahn was studying the effects that heavy metals (mercury, chromium, lead, and arsenic) have on living things. She was concerned about how these elements pollute the environment and cause disease in people. 

Rowley Monestier (2005) reviewed mechanisms of the induction of autoimmunity by the heavy metal mercury in the rat and mouse. In contrast to the rat autoimmune model, in the mouse model for autoimmunity induced by mercury, the autoantibody response is specifically targeted towards nucleolar antigens and is associated with induction of antifibrillarin autoantibodies. Second, exposure to low doses of mercury can dramatically worsen the development of autoimmune responses in lupus mouse models. A third difference is the nature of the interaction of heavy metals such as mercury with thiol groups and the role of this affinity in the availability of certain thiol-containing molecules for immature cells. 

Of the heavy metals, mercury has medical, socioeconomic, and environmental importance second only to lead. The most publicized cases of mercury poisoning have occurred in industrial settings. Table 10-1 lists the numerous occupations at risk for mercury exposure. By 1957, 80 industries used mercury for 3,000 purposes (Bidstrup 1964). The expression from Lewis Carroll s Alice in Wonderland, mad as a hatter, likely portrayed erethism, a condition caused by mercury poisoning of European and American hatters who used mercury to pack fur into watertight fabric. Acrodynia was another mercury-associated illness usually diagnosed in children taking mercury-based medications. 

Noncompetitive inhibition occurs when the inhibition depends only on the concentration of the inhibitor. This is usually caused by adsorption of the inhibitor at a site other than the active site but one which is necessary for activation. In other words, an inactive derivative of the enzyme is formed. Examples are the reaction of the heavy metals mercury, silver, and lead with sulfhydryl groups (—SH) on the enzyme. The sulfhydryl group is tied up by the heavy metal (ESH + Ag" " —> ESAg + H" ), and this reaction is irreversible. This is why heavy metals are poisons they inactivate enzymes in the body. 

D. Heavy Metals Mercury and silver precipitate proteins and inactivate sulfhydryl groups of enzymes but are used rarely because of toxicity. Organic mercurials such as nitromersol and thimerosal frequently cause hypersensitivity reactions but continue to be used as preservatives for vaccines, antitoxins, and immune sera. Merbromin is a weak antiseptic and stains tissues a bright red color. In the past silver nitrate was commonly used for prevention of neonatal gonococcal ophthalmia, but it has been largely replaced by topical antibiotics. Silver sulfadiazine (a sulfonamide) is used to decrease bacterial colonization in bums. 

Inclusion of the determination of heavy metals (mercury, cadmium, and lead) in fresh and frozen fish in the Official Food Control programs by member states is of outmost importance under the current circumstances. 

Determination of traces of pollutants has become very important. The environment and living organisms are especially vulnerable to the toxic heavy metals. In many cases, a simple and fast method for the determination of heavy metals is desirable. Enzymes which are inhibited by the heavy metals offer an interesting possibility in this context, and several applications of this idea have been made earlier such as for the determination of small concentrations of mercury and copper. We have shown that heavy metals (mercury) can also be detected, e.g., with the use of urease in combination with an IrTMOS ammonia sensor. Although several parameters can still be optimized, our results suggest that simple equipment for field use may be constructed around this type of sensor. The choice of enzyme (urease) was made out of convenience. There may be other enzymes which perform better. Furthermore the choice of enzyme will also determine the specificity of the enzyme-heavy metal system. It may be valuable to have both general heavy metal sensors as well as specific ones. 

Molybdenum is a transition metal in Group VI of the Periodic Table between chromium and tungsten. Although molybdenum is sometimes described as a heavy metal, its properties are very different from those of the typical heavy metals, mercury, thallium, and lead. Its position in the periodic table belies its toxicity. It is much less toxic than these and other heavy metals. Molybdenum s low toxicity makes it an attractive substitute for toxic metals in a number of applications, for example, in place of chromium in corrosion inhibitors and antimony in smoke suppressants [111]. 

At room temperature the heavy metal mercury (chemical symbol Hg) is a heavy, silvery liquid (specific gravity 13.5 kg/liter) with a high vapor pressure (0.16 Pa at 20°C). Thus, a saturated atmosphere contains approximately 15 mg Hg/m at 20°C [1]. 

Silicides are binary compounds of metals and silicon. Formulas are difficult to predict, and the bizarre stoichiometries often appear to be the reaction products found on freshman examinations. Silicides of most representative metals except beryllium are known, and most of the transition elements except silver, gold, and a few others form various silicides. The heavy metals mercury, thallium, lead, and bismuth do not react with silicon indeed, the molten metals are not even miscible with liquid silicon. 

The importance of the exposure of the human fetus and newborn to the three toxic heavy metals mercury, lead, and cadmium can be summarized in the following manner ... 

The development of probes for the toxic heavy metals mercury, cadmium and lead in biological systems is of special interest In this context, selectivity is particularly important since alkali and alkaline earth metals (e.g. Na", K", ... 

Besides the risks for health and equipment, the question of environmental compatibility of the disposal of lithium batteries after use and of scrap of the production has to be answered. The entire chemical, thermal, electric, and toxic aspects of the lithium battery technology have to be considered. The lithium metal is far less harmful than the heavy metal mercury. On the other hand thermal decomposition of a lithium high rate battery might be locally much more disastrous than a bursting alkali manganese or lead-acid battery. 

Among the heavy metals, mercury is a common component of certain oil and gas facilities. Its volatility accounts for its close association with lead and polonium, particularly in German wells where an imusual lead-mercury amalgam, termed altmarkite , has been recorded containing up to 30 wt% Hg. Mercury levels in the scales are so high that the metal is recovered commercially. Arsenic may be also present in... 

They exhibit EP (extraction procedure) toxicity. Wastes are EP-toxic if an extract from the waste is tested and found to contain high concentrations of heavy metals (mercury, lead, cadmium) or specific pesticides that could be released into the groundwater. 

---