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Fluorine occurs naturally in only a few organic compounds. In the chemical industry fluorine is a substituent of choice used to modify synthetic substrates in expectation of conferring beneficial physical properties. When incorporated, the spectroscopic properties of fluorine make it a useful tool to aid the structural elucidation of the derived substances. Fluorine is generally resistant to degradation...
This chapter describes the partitioning properties of organofluorine compounds in the environment. Partitioning in the air-water-octanol system is discussed using these pure substances as surrogates for real environmental systems consisting of air, water, natural organic matter and lipids. It is shown that the substitution of fluorine for hydrogen in alkanes, aromatics and carboxylic acids causes...
We review the available data concerning the atomospheric chemistry and environmental impact of hydrofluorocarbons (HFCs) and hydrofluoroethers (HFEs). HFCs and HFEs have no impact on stratospheric ozone. The direct global warming potentials of HFCs and HFEs are approximately an order of magnitude less than the CFCs they replace. At the concentrations expected from their atmospheric degradation, none...
Perfluorinated organic acids are ubiquitous in the environment at relatively low concentrations and appear to be highly persistent. Analytical techniques have relied primarily on GC-based methods, and for the lowest member TFA involve derivatization. The longer chain perfluoro acids have only recently been routinely analyzed at environmental concentrations using electrospray-MS/MS systems. Their analysis...
Although 3700 naturally occurring organohalogens are now known to exist, only relatively few contain fluorine. The presence of several fluoroalkanes in volcanic and other geothermal emissions is well documented, although exactly how these compounds are produced remains a mystery. Also unknown is the impact that these natural fluoroalkanes have on the global atmospheric budget compared to their anthropogenic...
An overview is given of the degradation and transformation of organic fluorine compounds by aerobic and anaerobic bacteria, yeasts, and fungi. Representatives of the major structural types of aliphatic, aromatic carbocyclic and heterocyclic compounds are included and a mechanistic view of the enzymology has been given where possible. Potential applications of organic fluorine compounds in biotechnology...
Perfluorofatty acids are used in increasing amounts as corrosion inhibitors, anti-wetting agents, surfactants, and in fire extinguishers. The perfluorofatty acids whose biological effects have been studied most extensively are perfluorooctanoic and perfluorodecanoic acids. The most dramatic effect of these xenobiotics in rats and mice is hepatic peroxisome proliferation, i.e., a considerable increase...
We have recently synthesized a series of monofluorinated polycyclic aromatic hydrocarbons (F-PAHs) and found that they provide a promising set of internal standards for environmental analysis of trace-level PAHs. Fluorine substitution has two antagonistic effects: the creation of a permanent dipole moment and the reduction of the London forces. As a result, F-PAHs are largely similar to the corresponding...
Fluoro substitution of polycyclic aromatic hydrocarbons (PAHs), which only slightly affects their steric and electronic properties, has served two main purposes. One has been to gain evidence about the mechanism of metabolic activation leading to tumor initiation by PA Hs. Studies with fluoro-substituted 5-methylchrysenes were useful in identifying the 1,2-dihydrodiol-3,4-epoxide as the ultimate carcinogenic...
The combination of phosphorus and fluorine has resulted in a variety of compounds that are unique in their physical and chemical properties as well as being some of the most toxic materials produced by man. A review of the chemistry and enzymatic basis for the toxicology of these compounds is presented. Catalytic enzymes that use these compounds as substrates and their potential applications are also...
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