Nature organochlorine compounds

Blais JM, Schindler DW, Muir DCG, et al. 1998. Accumulation of persistent organochlorine compounds in mountains of western Canada. Nature 395 585-588. 

In addition, chlorine derivatives are important as intermediates in the chemical industry, and there are numerous chlorine-containing pharmaceuticals for which no substitutes are presently available. Furthermore, organochlorine compounds, some very toxic, do occur naturally on a large scale. Clearly, however, we must endeavor to avoid adding unnecessarily to the natural load of toxins as the old adage goes, it is the dose that makes the poison.4 Certainly, problems exist that require an intelligent and chemically informed resolution, but the total ban advocated by some on the use of chlorine and chlorinated compounds is neither necessary nor acceptable. 

X-ray absorption spectroscopy has revealed the formation of organochlorine compounds from chloride and chloroperoxidase in weathering plant material (172-174). Moreover, this technique has uncovered the bromide-to-organobromine conversion in environmental samples (174). In addition to chloroperoxidase mediated chlorination, the abiotic chlorination in soils and sediments involving the alkylation of halides during Fe(III) oxidation of natural organic phenols in soils and sediments has been discovered (175-177). 

Hylin JW, Spenger RE, Gunther FA (1969) Potential Interferences in Certain Pesticide Residue Analyses from Organochlorine Compounds Occurring Naturally in Plants. Residue Rev 26 127... 

Boren, H. and Grimvall, A., Organochlorine compounds nature as the largest producer, Kemisk Tidskrift, 8, 26-28, 1996. 

In some of the early experiments, organochlorine compounds were detected by fluorescence when the chromatogram was sprayed with N-methylcarbazole or rhoda-mine B C 1 33. Also, fluorescence whiteners (1 4) known as Calcofluors, were used to visualize carbamates, uracils, and ureas. Both of these techniques, however, were only of a semi-quantitative nature. 

Pedit et al. [226] used a kinetic model for the scale-up of ozone/hydrogen peroxide oxidation of some volatile organochlorine compounds such as trichloroethylene and tetrachloroethylene. The kinetic model was applied to simulate the ozone/hydrogen peroxide treatment of these pollutants in a full-scale demonstration plant of the Los Angeles Department of Water and Power. The authors confirmed from the model that the reaction rate of the pollutant with ozone was several orders of magnitude lower than that with the hydroxyl radical. When considering that the natural organic matter acts as a promoter of hydroxyl radicals, the ozone utilization prediction was 81.2%, very close to the actual 88.4% experimentally observed. 

Although few in number, halogenated bipyrroles represent one of the most interesting and potentially important classes of natural organohalogens yet to be discovered. Like DDT, PCBs, and other anthropogenic organochlorine compounds, some halogenated bipyrroles seem to bioaccumulate up the food chain and at least one is found in humans. 

Simonich S. L. and Hites R. A. (1995) Global distribution of persistent organochlorine compounds. Nature (London) 269, 1851-1854. 

Organochlorine compounds with chlorine bonded to nitrogen give different oxidation products, depending on the nature of the organic molecule. 

Organochlorine compounds are specially noxious chemicals to humans and animals, due to their high toxicity, persistence, and cumulative ability (in soil, sediments of river bottoms, and particles suspended in surface-waters) and particularly because of their solubility in oils and fats (e.g. of warm-blooded animals). Easy dissemination of these chemicals — by air with dust and soot particles, and by water through rivers and ocean currents — increases the danger of contamination for all living things in the natural environment. The persistence and cumulative ability of these chemicals as well as their penetration into the food chain, creates special hazards to human health. 

S and N are cycled by life and by atmospheric photochemistry through many oxidation states. Natural Si and P compounds are involatile and less mobile in the environment. Environmental problems include acid rain, and pollution by soluble phosphates and organochlorine compounds. 

For organochlorine compounds with one Cl atom, such as CH3CI, we wiU expect to see a peak at M + 2 because there will be Cl present. The ratio (M + 2)/M will be the same as the natural ratio of Cl to Cl, that is, 32.7%, resulting in the same 1 /3 pattern seen in HCl. 

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