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Showing posts from July, 2009

The problem of high levels of nickel in soils and plants in the ultramafic area in Samar, Philippines

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Contributed by Janice P. Susaya, Sejong University, Seoul, Korea One of the heavy metals that commonly occur in elevated amounts in natural ecosystems is nickel (Ni). Ni is considered an essential micronutrient for plants, humans, and animals. It can exist in trace amounts in air, food, drinking water, and soils. Although Ni plays an important role in the metabolism of humans and animals, its intake in excesssive amounts or over a prolonged period could pose health ricsks. Studies have shown that children living in polluted areas have hypertrophy of tonsils, enlarged lymphatic nodes, and enlarged livers. There is also evidence that soluble Ni particulate is linked to acute lung injury. High Ni levels in natural ecosystems commonly come from ultramafic rocks (also called ultrabasic rocks). These are intrusive igneous rocks containing less than 45% silica (SiO2) with high concentrations of Ni, Mg, Fe, Cr, and Co. They are found in many places around the world and are common in many place...

A superheavy new element is named "copernicium"

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Source: Website of GSI Helmholtz Center for Heavy Ion Research, Darmstadt Element 112 in the periodic table is named in honor of the great astronomer Nicolaus Copernicus (1473-1543). Copernicus discovered that the Earth orbits the Sun ("heliocentric theory"), thus paving the way for our modern view of the world. The discovering team of scientists at the GSI Helmholtzzentrum für Schwerionenforschung (Center for Heavy Ion Research) in Darmstadt, Germany, led by Professor Sigurd Hofmann (photo) suggested the name „copernicium“ with the element symbol “Cp” for the new element 112. A few weeks ago, the International Union of Pure and Applied Chemistry, IUPAC, officially confirmed the discovery. In around six months, IUPAC will officially endorse the new element's name. This period is set to allow the scientific community to discuss the suggested name "copernicium" before it is finally accepted by IUPAC. Copernicus was born 1473 in Torun and died 1543 in Frombork, P...

Heavy metals in the environment and their health effects

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Heavy metals have a density of 6.0 g/cm3 or more (much higher than the average particle density of soils which is 2.65 g/cm3) and occur naturally in rocks but concentrations are frequently elevated as a result of contamination. The most important heavy metals with regard to potential hazards and occurrence in contaminated soils are: arsenic (As), cadmium (Cd), chromium (Cr), mercury (Hg), lead (Pb) and zinc (Zn). The sources of heavy metal pollutants are metal mining, metal smelting, metallurgical industries, and other metal-using industries, waste disposal, corrosions of metals in use, agriculture and forestry, forestry, fossil fuel combustion, and sports and leisure activities. Heavy metal contamination affects large areas worldwide. Hot spots of heavy metal pollution are located close to industrial sites, around large cities and in the vicinity of mining and smelting plants. Agriculture in these areas faces major problems due to heavy metal transfer into crops and subsequently into ...

Environmental pollution and the safety of herbal and alternative medicinal products

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There is scientific evidence that many over-the-counter health foods, neutraceuticals, and alternative medicinal products may not be safe. This was revealed in a paper written by Dr. K. Chan of Hongkong Baptist University and published in the international scientific journal Chemosphere. The paper concluded that “the increase in popularity of such products has brought concerns and fears over the professionalism of practitioners and the quality, efficacy, and safety of their treatment methods and products from herbal and natural sources. These products maybe contaminated with excessive or banned pesticides, microbial contaminants, heavy metals, chemical toxins or adulterated with orthodox drugs." "The excessive pesticides, microbial contaminants and heavy metals maybe related to the source of these herbal materials if they are grown under contaminated environment or during the collection of these plant materials. Chemical toxins may come from unfavorable or wrong storage condi...

F.A. Fallou: The Father of Soil Science

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History is one of the most complicated and subjective academic fields since it is greatly influenced by the knowledge, experience, interest, and personal taste of the authors who reconstruct the history of a given event or human endeavour. It also depends on the availability and accuracy of historical records as well as on the degree of detail of the historical account. The renowned historian Norman Davies author of the book "Europe: A History" (Pimlico, London, 1365pp) wrote that "history can be written at any magnification. One can write the history of the universe on a single page, or the life-cycle of a mayfly in forty volumes." Thus, it is not unusual to read many different versions or revisions of the historical account of a past event. The history of soil science is no exception. Some aspects of it are still controversial such as the one about its founder. Although the Russian geographer Vasilii Vasilevich Dokuchaev (1846-1903) is widely considered as the fou...