Toxicity fluoride

Reduction of cnviromncntal pollution requires lower energy use and new technology to decrease emission of gases such as sulfur dioxide and carbon dioxide, and to prevent toxic fluoride, heavy metal, and radioactive wastes from discharging into the environment. 

Farooqi, A., Masuda, H. and Firdous, N. (2007) Toxic fluoride and arsenic contaminated groundwater in the Lahore and Kasur districts, Punjab, Pakistan and possible contaminant sources. Environmental Pollution, 145(3), 839-49. 

Lambert SL, Kim DS (1994) Tank Waste Remediation System High-Level Waste Feed Processability Assessment Report. Westinghouse Hanford Company, C-SP-1143, UC-811 Lexa D (1997) Development of a substituted-fluorapatite waste form for the disposition of radioactive and toxic fluoride salt materials. Argoime National Laboratory Report ANL-NT-52, 21 p Lindberg ML, Ingram B (1964) Rare-earth silicate apatite from the Adirondack Mountains, New York. U S Geol Surv Prof Paper 501-B 64-65... 

EXPLOSION and FIRE CONCERNS nonflammable gas NFPA rating (none) can contain variable quantities of the low-sulfur fluorides (e.g., sulfur pentafluoride) which are highly toxic very reactive chemically, and corrosive in nature materials can hydrolyze on contact with water to yield highly toxic and very corrosive hydrogen fluoride may act as a simple asphyxiant when pure and in high concentrations incompatible with disilane may be explosive hazardous decomposition products include monosulfur fluoride, tetrasulflir fluoride, sulfuryl fluoride, sulfurous fluoride, sulfuric fluoride, decasulfur difluoride and other toxic fluoride compounds if cylinders are involved in a fire, keep cool with water spray. 

Hazardous Decomp. Prods. Temps, above 750 F may result in release of toxic fluoride-contng. fumes (tetrafluoroethylene, hexafluoropropylene, perfluoroisobutylene, carbon fluoride)... 

Precaution Flamm. uel 21.3%, lei 5.5% may form explosive mixts. in air incompat. with oxidizers can react violently with hydrogen chloride alkyl boron/alkyl hyponitrite compds. initiate polymerization forms peroxides with pure oxygen heat-sensitive Hazardous Decomp. Prods. CO, CO2, hydrogen fluoride heated to decomp., emits toxic fluoride fumes emits toxic fumes underfire conditions... 

Di-0-benzyl-2-deoxy-2-phthalimido- 3-D-glucopyranosyl assume toxic fluoride (17) [18] (314 mg, 0.64 mmol)... 

Several breakdown processes have been used in which the ore is reacted with a fused or sintered fluorinating agent such as potassium hydrogen fluoride or sodium silicofluoride. The most important of these is the Copaux-Kawecki process for opening beryl ore. This is in many ways a unique process and other processes are unlikely to have many features in common with it apart from the problems associated with the handling of toxic fluorides. Since the fluorine is in combination with sodium, as the simple fluoride or as stable complexes with silicon and iron, the severe corrosion conditions inherent in many other fluorination reactions are almost absent in this case. 

Sulfur hexafluoride is made commercially by the direct fluorination of molten sulfur. Some higher and lower toxic fluorides formed in the process are removed, and the commercial product is more than 99.5 mole percent pure. A high-purity etchant grade is also available for the electronics industry. Common impurities include small amounts of carbon tetrafluoride, nitrogen, and water vapor. 

Relatively few nonmetals require determination in biological samples. One important example is potentially toxic fluoride, which occurs in biological fluids as the fluoride ion, F". Fluoride in appropriately processed samples is readily determined potentiometrically with a fluoride ion-selective electrode. 

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