Geochemistry and the Environment Volume I: The Relation of Selected Trace Elements to Health and Disease (1974) / Chapter Skim
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Pages 79-88
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on Advances in Water Pollution Research, Tokyo, 0.
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X Analytical Methods GEORGE H MORRISON, Co-Chairman JAMES 0.
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silicon fluorides, depending on the temperature. Hightemperature ashing of fluorine-containing compounds is best done under alkaline conditions (Bussmann and Hanni, 1967)
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82 THE RELATION OF SELECTED TRACE ELEMENTS TO HEALTH AND DISEASE TABLE 29 Methods of Measurement of Iodine Amount or Technique Material Concentration Atomic emission Synthetic 2ng Thyroid, freeze lpg dried Spectrophotometry Organically bound 1 Serum bound I Fluorescence Synthetic 1-10 pg Titration Urine Ion-selective-electrode Idealized system 3 pg/1 Electrochemistry Idealized system 0.1 ~o&M 2 X 10-6% Gas chromatography Idealized system Neutron-activation Aerosol particles Active charcoal ftlter Protein bound 1General biologicals 4 X 10-4 ppm Blood Photo-activation Seawater Hair, blood, wood, 0.2pg tobacco Catalytic Blood Soil General biologicals Spark-source mass Human hair 0,03 1-'8 spectrometry X-ray fluorescence Pharmaceuticals and solid-sample techniques. In the former, illustrated by atomic absorption or anodic stripping voltammetry, the detection limit experimentally determined is a concentration detection limit (Osteryoung and OsterDetail Comment (Reference)
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Analytical Methods 83 of sample actually involved in the analysis. From this quantity, the concentration detection limit can be derived.
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00 ~ TABLE 31 Limits of Detection of Analytical Methods Used in Trace Analysis4 Concentration Detection Limits of the Element in a Sample, ppb Absolute Detection Limits, ng Aqueous Solutionsb Biological Materialsc Geological MateriaJsd Analytical Method Cd Pb Zn Cd Atomic absorption Nebulizer-flamee 3 30 3 3 Nonflamef 0.002 O.o2 0.002 0.02 Emission spectroscopyK 0.7 10 I 3.5 Anodic stripping voltammetrye 0.05 0.1 0.1 0.05 Atomic fluorescence Nebulizer-flamee 0.001 10 0.02 0.001 Nonflamef 0.00003 0.01 0.00005 0.0003 Spark-source mass spectroscopy [ approx. 0.1-1 [ Neutron-activationh 5 1000 10 5 Electron-probe [ approx.
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As another electrochemical technique, pulse anodic stripping, using a hanging mercury drop electrode, appears competitive with the thin-layer mercury electrode. Both are more demanding of operator skill than atomic absorption, and both require addition of a reagent, which must be carefully purified to assure negligible blanks.
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86 THE RELATION OF SELECTED TRACE ELEMENTS TO HEALTH AND DISEASE for the determination of chromium, although this method is less sensitive (by a factor of I 0) than others, even with the use of special organic solvents (Woehlbier et aL.
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chloroform. The chloroform is evaporated, and the chromium is taken up in 4-methyl-2-pentanon (Cary and Allaway, 1971 )
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88 THE RELATION OF SELECTED TRACE ELEMENTS TO HEALTH AND DISEASE Taves, D
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