Blood analysis toxic metals

Level 2 Laboratories. Thirty-seven labs also participate in Level 2 activities. At this level, laboratory personnel are trained to detect exposure to a limited number of toxic chemical agents in human blood or urine. Analysis of cyanide and toxic metals in human samples are examples of Level 2 laboratory activities. 

Metal analysis of bio-monitoring samples, such as blood, urine, saliva, semen, skin, internal and external body parts outside clinical testing, is often required to support toxicological and other studies. Screening of samples for metals analysis may be used to expose the presence of toxic metals in water, air pollution or foods consumed by the public. Some elements that are essential nutrients at low levels can be toxic at higher levels and some are toxic at any level. 

Bearse, R.C., Close, D.A., Malanify, J.J., and Umbarger, C.J. (1974). Elemental analysis of whole blood using proton-induced X-ray emission. Anal. Chem., 4 , 499-503 Berman, E. (1980) Toxic metals and their analysis, Heyden, London, Philadelphia, Rheine Brown, A.A., and Taylor, A. (1984) Determination of copper and zinc in serum and urine by use of slotted quartz tube and flame atomic absorption spectrometry. Analyst, 109. 1455-1459... 

The determination of trace metal impurities in pharmaceuticals requires a more sensitive methodology. Flame atomic absorption and emission spectroscopy have been the major tools used for this purpose. Metal contaminants such as Pb, Sb, Bi, Ag, Ba, Ni, and Sr have been identified and quantitated by these methods (59,66-68). Specific analysis is necessary for the detection of the presence of palladium in semisynthetic penicillins, where it is used as a catalyst (57), and for silicon in streptomycin (69). Furnace atomic absorption may find a significant role in the determination of known impurities, due to higher sensitivity (Table 2). Atomic absorption is used to detect quantities of known toxic substances in the blood, such as lead (70-72). If the exact impurities are not known, qualitative as well as quantitative analysis is required, and a general multielemental method such as ICP spectrometry with a rapid-scanning monochromator may be utilized. Inductively coupled plasma atomic emission spectroscopy may also be used in the analysis of biological fluids in order to detect contamination by environmental metals such as mercury (73), and to test serum and tissues for the presence of aluminum, lead, cadmium, nickel, and other trace metals (74-77). 

The first requirement can be easily fulfilled by the preconcentration of the analyte before the analysis. Preconcentration has been applied to sample preparation for flame atomic absorption (25) and, more recently, for ICP (79,80) spectroscopy. However, preconcentration is not completely satisfactory, because of the increased analysis time (which may be critical in clinical analysis) and the increased chance of contamination or sample loss. Most important, however, a larger initial sample size is necessary. The apparent solution is a more sensitive technique. Table 2 lists concentrations of various metals in whole blood or serum (81,82) in comparison to limits of detection for the various atomic spectroscopy techniques. In many cases, especially for the toxic heavy metals, only flameless atomic absorption using a graphite furnace can provide the necessary sensitivity and accommodate a sample of only a few microliters (Table 1). The determination of therapeutic gold in urine and serum (83,84), chromium in serum (85), skin (86) and liver (87), copper in semen (88), arsenic in urine (89), manganese in animal tissues (90), and lead in blood (91) are but a few examples in analyses which have utilized the flameless atomic absorption technique. 

Tlien, three decades later, independently but almost simultaneously, Kehoe in Cincinnati [3] and Teisinger in Prague [4] demonstrated the presence of lead in the blood of persons who were not industrially exposed. Over the following years the wide spectrum of application for the analysis of toxic heavy metals in blood endowed this approach with greater importance than hair analysis. However, the sensational results of forensic analysis ensured that hair analysis was not completely forgotten. 

Samples such as hair, nails, blood, urine, and various tissues are analyzed by NAA for both essential and toxic trace elements (Bhandari et al. 1987, Lai et al. 1987). The analysis can be related to determine their effect on disease outcomes. These authors have reported that the diet and environment contribute largely towards the trace elements in the human body. It is has been demonstrated in other works that the selenium concentration in human nails is an accurate monitor of the dietary intake of selenium. As a consequence, the nail monitor has been extensively used to study the protective effect of dietary selenium against cancer and heart disease in numerous prospective case-control studies. In another study by Kanabrocki et al. (1979) on human thumbnails in USA, using thermal NAA technique, the average concentration of metals studied in clinically symptom-free adult female and male subjects were found to be zinc, 184 vs. 153 ppm chromium, 6.8 vs. 4.2 selenium, 0.9 vs. 0.6 gold, 2.6 vs. 0.4 mercury, 1.9 vs. 0.4 silver 0.7 vs. 0.3 cobalt, 0.07 vs. 0.04. In another study, the fluorine concentration in bone biopsy samples was... 

A healthy 46-year-old patient developed progressively worsening symptoms of cobalt toxicity following 6 months of synovectomy and replacement of ceramic-on-ceramic hip bearing to a metal-on-polyethylene bearing. Blood cobalt concentration peaked at 6521 p /L. The patient died from cobalt-induced cardiomyopathy. Implant retrieval analysis confirmed a loss qf28.3g mass cfthe cobalt-chromium femoral head as a result of severe abrasive wear by ceramic particles embedded in the revision polyethylene liner [83 ]. 

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