Potosi mine in Bolivia was the largest one of silver, where mercury amalgam method was used in 16th to 18th century. The total amount of used mercury was estimated at 7500 tons, which is 12 times as much as in Minamata, Japan. First, the atmospheric diffusion of mercury at Potosi was calculated with the atmospheric dispersion model. The fall mercury distributed in the normal distribution over a...

A review is given of a relatively unknown area of the electronic structures of Rydberg radicals. The primary examples of such structures are H , NH4 and H30. The condensed phase existence of the latter 8wo has long been proposed. Mercury amalgams of organic ammonium radicals, R4N, have been reported. Theoretical studies are reported on some of these species. in liquid ammonia vis-a-vis NH4 + e ...

Gold extraction and its commercialization in the Amazon region is mainly by rudimentary procedures. Therefore, during the process of extraction and recovery of this precious metal, large amounts of mercury vapors are thrown into the environment. This paper is an attempt to establish a correlation between the concentration of total mercury in the urine of workers at the gold shop in the Municipa...

The three modern "faces" of mercury are our perceptions of risk from the exposure of billions of people to methyl mercury in fish, mercury vapor from amalgam tooth fillings, and ethyl mercury in the form of thimerosal added as an antiseptic to widely used vaccines. In this article I review human exposure to and the toxicology of each of these three species of mercury. Mechanisms of action are d...

OBJECTIVES This study was carried out for the purpose of evaluating the blood mercury concentration of the residents of Busan, Korea, as well as the relationship between the mercury concentration and the pattern of fish consumption along with other epidemiological factors. METHODS Two hundred ninety-three subjects (147 men and 146 women), who were aged 40 years or more, were recruited into th...

For Canadians with amalgam-filled teeth, it was estimated that total mercury (Hg) exposure averages: 3.3 µg Hg/day in toddlers (aged 3 to 4 years); 5.6 µg Hg/day in children (aged 5 to 11 years); 6.7 µg Hg/day in teens (aged 12 to 19 years); 9.4 µg Hg/day in adults (aged 20 to 59 years); and 6.8 µg Hg/day in seniors (aged 60+ years). Of this exposure, amalgam was estimated to contribute 50% to ...

The reduction of the Cd(2,2,2)2+ complex has been studied in acetonitrile using polarography, chronocoulometry, and cyclic voltammetry. The corresponding kinetic parameters have been calculated and are compared with those obtained for the solvated cadmium cation in the same solvent. The study of the eiectrochemical reduction mechanism showed that the final stable products are the free ligand (2...

The physical properties of amalgam are influenced by various manipulative factors such as mercury-alloy ratio, mixing time, existence of a ball in the capsule in the process of mixing, condensation pressure and the twisting movement given to the amalgam mix by the plugger in the process of condensation[1-8]. These factors, on the whole, determine the properties of amalgam restorations. It is cl...

background: many attempts have been performed and continued for improvement of dental amalgam properties during last decades. the aim of present research was fabrication and characterization of amalgam/titania nano composite and evaluation of its corrosion behavior. materials and methods: in this experimental research, nano particles of titania were added to initial amalgam alloy powder and the...

To assess amalgam use and waste management protocols practised by Pakistani dentists, a cross-sectional study was made of 239 dentists in Islamabad and Rawalpindi, recruited by convenience and cluster sampling. Amalgam was the most frequently used restorative material, with the choice dictated by patients' financial constraints. While 90.4% of dentists perceived amalgam as a health risk, only 4...