Trace elements fluoride

Two methods were examined for digestion of biological samples prior to trace element analysis. In the first one a nitric acid-hydrogen peroxide-hydrofluoric acid mixture was used in an open system, and in the second one nitric acid in a closed Teflon bomb. The latter method was superior for Ge determination, however, germanium was lost whenever hydrogen fluoride had to be added for disolving sihcious material. End analysis by ICP-AES was used for Ge concentrations in the Xg/g range13. 

Clinical syndromes are associated with deficiencies of the following trace elements zinc, copper, manganese, selenium, chromium, iodine, fluoride, molybdenum, and iron. 

Nixon277 compared atomic absorption spectroscopy, flame photometry, mass spectroscopy, and neutron activation analysis as methods for the determination of some 21 trace elements (<100 ppm) in hard dental tissue and dental plaque silver, aluminum, arsenic, gold, barium, chromium, copper, fluoride, iron, lithium, manganese, molybdenum, nickel, lead, rubidium, antimony, selenium, tin, strontium, vanadium, and zinc. Brunelle 278) also described procedures for the determination of about 20 elements in soil using a combination of atomic absorption spectroscopy and neutron activation analysis. 

Trace element retention on earth materials is illustrated in several case studies, where selected contaminants (e.g., fluoride, cesium, mercury) interact with rocks, clays, soils, and sediments under different environmental conditions (e.g., pH, presence of organic ligands, salinity). 

Fluorine is an essential element involved in several enzymatic reactions in various organs, it is present as a trace element in bone mineral, dentine and tooth enamel and is considered as one of the most efficient elements for the prophylaxis and treatment of dental caries. In addition to their direct effect on cell biology, fluoride ions can also modify the physico-chemical properties of materials (solubility, structure and microstructure, surface properties), resulting in indirect biological effects. The biological and physico-chemical roles of fluoride ions are the main reasons for their incorporation in biomaterials, with a pre-eminence for the biological role and often both in conjunction. This chapter focuses on fluoridated bioceramics and related materials, including cements. The specific role of fluorinated polymers and molecules will not be reviewed here. 

Fluoride is a cumulative toxin, which accumulates in mineralized tissues, notably in the lattice of bone and tooth crystals [8,39]. The biological effects in humans due to chronic fluoride ingestion depend not only on the total dosage and duration of exposure, but also on associated factors such as nutritional status, functional status of the renal tissue and interaction with other trace elements [41]. The effect of... 

Another analytical procedure for sample preparation including analyte separation and enrichment is the coprecipitation of the trace elements to be determined. The co-precipitation behaviour of Ti, Mo, Sn and Sb under two different fluoride forming conditions (at < 70 °C in an ultrasonic bath and at 245 °C using a Teflon bomb) has been studied to improve the accuracy of the trace analysis of these elements in Ca-Al-Mg fluorides, by ICP-MS.14 The applicability of this analytical method (including isotope dilution technique) was demonstrated for four carbonaceous chondrites and silicate reference materials of basalt or andesite.14... 

Heavy metals stimulate or inhibit a wide variety of enzyme systems (16, 71, 72), sometimes for protracted periods (71, 73). These effects may be so sensitive as to precede overt toxicity as in the case of lead-induced inhibition of 8 ALA dehydrase activity with consequential interference of heme and porphyrin synthesis (15, 16). Urinary excretion of 8 ALA is also a sensitive indicator of lead absorption (74). Another erythrocytic enzyme, glucose-6-phosphatase, when present in abnormally low amounts, may increase susceptibility to lead intoxication (75), and for this reason, screens to detect such affected persons in lead-related injuries have been suggested (76). Biochemical bases for trace element toxicity have been described for the heavy metals (16), selenium (77), fluoride (78), and cobalt (79). Heavy metal metabolic injury, in addition to producing primary toxicity, can adversely alter drug detoxification mechanisms (80, 81), with possible secondary consequences for that portion of the population on medication. 

Electrochemical techniques anodic stripping voltammetry (ASV) and cathodic stripping voltammetry (CSV) for determining trace elements, and potentiometric sensors for determining dissolved gases (C02, N02, S02, NH3, H2S, HCN, and HF) as well as chloride, fluoride, cyanide, and sulfide. 

There is a great deal of both popular and professional interest in the etiology, diagnosis, prevention, and treatment of osteoporosis. The extent of this disease in the United States is a major public health concern. No single cause can be identified. Certainly the influence of hormones, dietary intakes of Ca, fluoride and vitamin D are significant. Our results suggest that it may be prudent to consider the possibility that trace element deficiencies, particularly of Mn, may be of significance. 

Patterson, M.M. et al., Assessment of Ambient, Plant Tissue, and Soil Fluoride Concentrations Associated with Phosphate Fertilizer Plant, Proceedings of Biogeochemistry of Trace Elements Conference, University of Guelph, Guelph, Ontario, Canada, 2001. 

Trace elements in this category would include fluoride used for protection against dental caries and lithium salts used in the treatment of manic depression. The dosages required for a beneficial pharmacological effect greatly exceed the amounts of these elements normally found in food. 

Trace elements include chromium, cobalt, copper, fluoride, iron, manganese, molybdenum, selenium, and zinc. 

More than 15 additional trace elements are considered by some investigators to have a potentially important role in human medicine. A review by Nielsen considers these in detail and discusses emerging concepts of essentiality. For some such as lead, cadmium, arsenic, aluminum, and nickel, the clinical laboratory will primarily consider them as toxic elements (see Chapter 35). Others, such as lithium and fluoride, are classified as pharmacologically beneficial and monitoring of dosage may be required. Some elements can be considered nutritionally beneficial and are reported to produce restorative health effects at lower dosages. Evidence comes mainly from animal studies when dietary depletion of the element is combined with other metabohc, hormonal, or physiological stressors. ... 

Fluoride (Fl) is the most widely used of the pharmacologically beneficial trace elements in the area of public health. Dental caries has been described as the last major epidemic of preventable bacterial disease and dental decay leads to tooth loss, nutritional problems, and systemic infections. ... 

Dr. Churchill, read McKay s reports and ordered a test that identified trace elements in water using a new quartz spectroscope. The instrument identified fluoride in the deep wells only. McKay then obtained samples of drinking water from the many communities where he knew mottled enamel was found and Churchill confirmed the presence of fluoride. The association of fluoride with mottled enamel was published in the Scientific American in 1931. 

In certain cases, the trace element is kept in solution as a less volatile complex during the distillation of the sample matrix. In the determination of boron traces in chlorosilanes, silicon is removed as the volatile fluoride complex. To prevent the formation of volatile BF3, mannitol is added to form a non-volatile complex with boron [113]. 

Pine needles Apple leaves Peach leaves Spinach leaves Tomato leaves Vegetation Sargasso seaweed SRM 1575 SRM 1515 SRM 1547 SRM 1570a SRM 1573a SRM 2695 NIES-9 M M 11 t1 M M H t M fluoride trace elements n II II II II II NIES II II II 49... 

The discussion about trace elements or minerals, their role, their optimal concentrations, and of how these may be vital to health and well-being continues. The water fluoridation controversy, of fluoride vs. tooth decay, is related. How much is not enough, and how much is too much Not only with regard to fluoride addition to public water supplies, but with regard to the intervention of the state. Should the state doctor all municipal water supplies to maintain a uniform and apparently optimal mineral content When is it and when is it not the state s business ... 

Nielsen FH (1984a) Effects in rats of boron deprivation and of interactions between boron and fluoride, aluminium, magnesium, or calcium. In Mills CF, Bremner I and Chesters JK, eds. Trace Element in Man and Animals-5. Commonwealth Agricultural Bureaux, Famham Royal, UK, pp. 271-275. 

WHO (1996) Fluoride. In Trace elements inhuman nutrition and health, pp. 187-195. World Health Organization, Geneva. 

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