Historical Lead Deposits

AH the time up to the Middle Ages lead was a by-product in the working of silver ores. In the period ad 700-1200 mines were opened in the present Germany (Rhineland, Harz and Saxony), the present Poland (Silesia) and the present Czech Republic (Bohemia). The ores were mainly lead ores, but the mines were called silver mines. Lead, produced from these deposits, can now be found in decorative fixtures, roofs, pipes and windows in castles and cathedrals all over Europe. 

In the USA the first lead mines were opened in 1621 and new deposits were found as settlement spread westwards. In the 19 century many great lead ore finds were made in different parts of the world, in Mexico and Austraha among other countries. The breakthrough in the 1920s of the ore dressing technique by flotation made it possible to separate the different minerals in complex ores. This increased the number of workable lead deposits. 

In Sweden a silver-rich lead ore was mined in Sala from the beginning of the 16 century but lead was not taken care of until the middle of the 18 century. Today Sweden is the largest lead producer in Europe, mainly due to the great deposit in Laisvall in the north of the country. Mining there began in 1943. 

Galena PbS is the most important ore mineral of lead and an important source of silver. Galena occurs in limestone, dolomite and sandstone as dissemination in veins. 

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The expected annuahzed inputs of lead via atmospheric emissions into other environmental compartments (see Chapter 5) must be balanced against the enormous quantities of postdeposition lead sequestered in soils, dusts, sediments, etc. over previous centuries, especially after the introduction of lead additives for fuels and the use of lead pigments in paints. Current lead inputs to environmental compartments wiU, through accumulation, be added to the historical lead deposition amounts. 

The result common to aU the studies discussed above, both the historical sediment records and the studies examined by Thomas et al. (20), is the dramatic decrease in lead deposition in the past 15 years (7, 8, 15, 33, 417, 419 30). Whether the drop is attributable mainly to decreased gasoline emissions or to a combination of decreases in automobile, industrial, and other emissions, the existence of the trend is unambiguous. The large quantities of anthropogenic lead already in the environment, though, require continued attention. The remediation of contaminated soil and water, the treatment of lead poisoning, and the elucidation of the mechanisms of lead toxicity are all areas in which a firm understanding of the fundamental chemistry of lead complexes can contribute dramatically. 

Lead in soil is a mixture of lead deposited from the atmosphere, natural lead in the parent rock material from which the soil was formed, and lead from other sources, such as paint chips. Historically, the atmospheric component... 

Owing to historical considerations and military specifications on maximum permissible carbon content in tin and tin-lead deposits, matte tin or satin tin is generally plated for rigorous solderability applications such as PWBs and electronic components. Because of its higher hardness and lower susceptibility to staining, bright tin is usually selected for connector... 

Renberg, I., Bindler, R. and Braimvell, M.-L. 2001. Using the historical atmospheric lead deposition record as a chronological marker in sediment deposits in Europe. The Holocene 11, 511-516. 

Somatotropin, the P-adrenergic agonists, and the anaboHc steroids are considered metaboHsm modifiers because these compounds alter protein, Hpid, carbohydrate, mineral metaboHsm, or combinations of these and they partition nutrient use toward greater rates of protein deposition, ie, muscle growth, and lesser rates of Hpid accretion. Historical data leading to understanding of the mechanism (s) of action are found in reviews on anaboHc steroids (1), somatotropin (2—4), and the phenethano1 amines (5—7). 

Stationary batteries, moreover, often have transparent containers historically, probably to allow observation of the electrolyte level or the extent of shedding. Deposits of oily substances accumulating at the electrolyte surface due to their stickiness could gather lead particles and produce an unpleasantly dirty rim, which can be avoided by careful selection of suitable oils [53J. 

The primary source of lead in the environment has historically been anthropogenic emissions to the atmosphere. In 1984, combustion of leaded gasoline was responsible for approximately 90% of all anthropogenic lead emissions. EPA phased out the use of lead alkyls in gasoline, however, and by 1990, auto emissions accounted for only 33% of the annual lead emissions (EPA 1996h). Use of lead additives in motor fuels was totally banned after December 31, 1995 (EPA 1996f). The ban went into effect on February 2, 1996. Atmospheric deposition is the largest source of lead found in soils. Lead is transferred... 

The historic use of trace-element geochemistry around the McArthur River Uranium Deposit has primarily focussed on a limited suite of elements, including uranium, lead, nickel, copper, and boron. At McArthur River, uranium is distributed around the main deposit to significant distances (100 s of meters) in the overlying Athabasca Group (McGill et al. 1993), yet variations in the uranium content of this halo is typically restricted to 1-3 parts per million with little spatial variation, restricting one s ability to vector... 

The wide range of potential sources and their environmental persistence may well explain why PCDDs and PCDFs are ubiquitous. It is believed that there are two main routes by which PCDDs and PCDFs are released into the environment via the atmosphere leading to deposition on soil, water and plants and via solid or liquid waste with subsequent contamination of land (e.g. sewage sludge). These findings should help to reduce the already extensive effort needed to trace back the contamination to its sources, although the persistence of PCDDs and PCDFs in the environment for many years means that historical as well as current sources need to be taken into account. 

In the case of lead arsenate (acid form), calcium arsenate, and sodium arsenate, the Pb-isotopic compositions closely match those of sulfides from porphyry copper deposits from southeastern Arizona, specifically from the Pima and Silver Bell districts (Bouse et al., 1999). Notably, other major historical producers of arsenic trioxide (e.g., Anaconda Copper Co., US Smelting Co., Jardine Mining Co.) used... 

Table 1.1 lists some historical "firsts" with regard to nuclear weapons. The extensive tests in the atmosphere up to 1963 lead to a large global q>read of tritium, fission products and actinides. Scimtists have used this to learn more about global wind and water currents. Radiochemists have studied the migration of deposited radionuclides, as discussed in Chapter 22, radioecologists the uptake of radioactive elements by plants and animals, as described in Chapter 18, etc. 

Gulson BL, Davis JJ, Mizon KJ et al (1995a) Sources of lead in soil and dust and the use of dust fallout as a sampling medium. Sci Total Environ 166 245-262 Gulson BL, Mahaffey KR, Mizon KJ et al (1995b) Contribution of tissue lead to blood lead in adult female subjects based on stable lead isotope methods. J Lab Clin Med 125 703-712 Hageman KJ, Simonich SL, Campbell DH et al (2006) Atmospheric deposition of current-use and historic-use pesticides in snow at national parks in the western United States. Environ Sci Technol 40 3174-3180... 

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