Other Chlorinated 2-Compounds

Dilling WL, Tefertiller NB, Kallos GJ. 1975. Evaporation rates and reactivities of methylene chloride, chloroform, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethylene, and other chlorinated compounds in dilute aqueous solutions. Environmental Science and Technology 9 833-838. 

Gotz R, P Friesel, K Roch, O Papke, M Ball, M, A Lis (1993) Polychlorinated-/ -dioxins PCDDs, dibenzofu-rans PCDFs, and other chlorinated compounds in the River Elbe results on bottom sediments and fresh sediments collected in sedimentation chambers. Chemosphere 27 105-111. 

Methoxychlor [1,1,l-trichloro-2,2-bis(p-methoxyphenyl)-ethane], benzene hexachloride (BHC), chlordan, and toxaphene are chlorinated compounds of recognized importance in the insecticide field. Other chlorinated compounds now undergoing-field testing experiments will, no doubt, soon be added to the list. The need for specific analytical methods is familiar to those concerned with the analysis of formulations containing one or more of the above insecticides. 

Sanchez, J., M. Sole, and J. Albaiges. 1993. A comparison of distributions of PCB congeners and other chlorinated compounds in fishes from coastal areas and remote lakes. Inter. Jour. Environ. Anal. Chem. 50 269-284. 

One case study was identified where a man who had been occupationally exposed to hexachloroethane was treated for a liver tumor (Selden et al. 1989). Exposure had occurred over a period of 6 years as a result of the presence of hexachloroethane in a degassing agent used during aluminum smelting. However, the hexachloroethane reacted at the 700 C use-temperature, releasing a gas that was 96% hexachlorobenzene with small amounts of other chlorinated compounds. Because there was occupational exposure to a mixture of chlorinated compounds rather than just hexachloroethane, it is highly unlikely that the tumor was the result of hexachloroethane exposure alone. Occupational exposure to mineral oil mists for 20 years was also part of the subject s employment history. 

Cancer. Only one report was located regarding an association between hexachloroethane and cancer in humans (Selden et al. 1989). In this study a liver tumor was found in an adult male who had used a product containing hexachloroethane at work for 6 years. However, under the conditions of use, the hexachloroethane reacted to form hexachlorobenzene and other chlorinated compounds which were as likely, or more likely, to have contributed to the tumorigenesis as the hexachloroethane. 

The relative ratio of regioisomers of PCDD/F and other chlorinated compounds formed in incinerators is called the incineration pattern. The pattern can be derived from statistical analysis of a large number of measurements of the same plants, and can be used for elucidation of thermal formation mechanisms in plants. In principle regioisomers can be formed either by stereospecific chlorination or dechlorination processes. The pattern has also been used as a part for explaining of the formation mechanism of PCDD/F and other chlorinated compounds formed in incinerations (see Figure 8.4). 

Toxic fumes of phosgene and hydrogen chloride may form when exposed to an open flame (CHRIS, 1984). Chlorobenzene is stable up to 700 °C but in combination with other chlorinated compounds, it is stable up to 900 °C (Graham et al, 1986). 

C for 24 h (Bevenue and Beckman, 1967). Wet oxidation of pentachlorophenol at 320 °C yielded formic and acetic acids (Randall and Knopp, 1980). in a dilute aqueous solution at pH 6.0, pentachlorophenol reacted with excess of hypochlorous acid forming 2,3,5,6-tetrachlorobenzoquinone (3% yield), 2,3,4,4,5,6-hexachlorobenzoquinone (20% yield), and two other chlorinated compounds (Smith et al., 1976). 

Uses. 1,2-Dichloroethylene is used as a solvent for organic materials and as an intermediate in the synthesis of other chlorinated compounds it may be produced by the chlorination of acetylene but is often produced as a by-product in the manufacture of other chlorinated compounds. 

HCZyme has been demonstrated in bench-scale tests and at field remediations to be effective on benzene, toluene, ethylene, and xylene (BTEX), Polycyclic aromatic hydrocarbons (PAHs), trichloroethylene (TCE), dichloroethylene (DCE), mineral spirits, fuel oils, motor oils, and hydraulic fluids. The vendor claims that HCZyme has been tested and used on over 2 million tons of petroleum-contaminated soils and is effective in breaking down petroleum hydrocarbons, polychlorinated biphenyls (PCBs), creosote, sludges, waste oils, free product, tank bottoms, and other chlorinated compounds (D18208L, p. 15). 

The base-catalyzed decomposition (BCD) technology is a chemical dechlorination technology for the ex situ treatment of soils, sludges, and liquids contaminated with PCBs and other chlorinated compounds. In the two-step process, chlorine atoms on chlorinated molecules are removed and replaced by hydrogen atoms, using heat and commonly available chemicals in the presence of a catalyst. 

The importance of catalysts in chemical reactions cannot be overestimated. In the destruction of ozone previously mentioned, chlorine serves as a catalyst. Because of its detrimental effect to the environment, CFCs and other chlorine compounds have been banned internationally. Nearly every industrial chemical process is associated with numerous catalysts. These catalysts make the reactions commercially feasible, and chemists are continually searching for new catalysts. Some examples of important catalysts include iron, potassium oxide, and aluminum oxide in the Haber process to manufacture ammonia platinum and rhodium in the Ostwald synthesis of nitric... 

You are encouraged to do your own personal research. Many websites, such as www.ejnet.org/dioxin, will tell you POPs are a problem of epic proportions. Others, such as www.c3.0rg, will point to evidence showing that the concentration of POPs in humans has been reduced dramatically over the past 30 years, while the production of PVC and other chlorine compounds has more than tripled. Chlorine is indeed a wonder chemical, but as with any technology, we need to make sure that the benefits are well worth the risks. Becoming a well-informed citizen is a good place to start. 

Carbon Tetrachloride or other Chlorinated Compounds.— These products, having density above 1, increase the specific gravity of oil of turpentine, and lower its boiling point. They may be identified by testing for chlorine as follows ... 

All three chloroacetic acids (chloroacetic acid [MCA], dichloroacetic acid [DCA], and trichloroacetic acid [TCA]) are naturally occurring (7), with TCA being identified in the environment most frequently (reviews (278, 405 108)). However, these chlorinated acetic acids also have anthropogenic sources. The major source of natural TCA appears to be the enzymatic (chloroperoxidase) or abiotic degradation of humic and fulvic acids, which ultimately leads to chloroform and TCA. Early studies (409) and subsequent work confirm both a biogenic and an abiotic pathway. Model experiments with soil humic and fulvic acids, chloroperoxidase, chloride, and hydrogen peroxide show the formation of TCA, chloroform, and other chlorinated compounds (317, 410-412). Other studies reveal an abiotic source of TCA (412, 413). 

Much of the effort on environmental chemicals that contaminate food has concentrated on a small range of chlorinated chemicals. In addition to the chlorinated PCDDs, PCDFs and PCBs already mentioned, other chlorinated compounds can be separated into two groups chlorinated aromatic compounds and chlorinated aliphatic compounds. Although there is a number of organochlorine pesticides that are persistent in the environment, these will not be considered here, as they comprise an extensive field of study in their own right. 

The solvent extract should be subjected to one or more cleanup steps for the removal of interfering substances. The presence of phthalate esters, sulfur, or other chlorinated compounds can mask pesticide peaks. The extract should, therefore, be cleaned up from the interfering substances using a florisil column or by gel permeation chromatography (see Chapter 1.5). The distribution patterns for the pesticides in the florisil column fractions are presented in Table 2.20.2. 

Newsome, W.H., Ryan, J.J., 1999. Toxaphene and other chlorinated compounds in human milk from northern and southern Canada A comparison. Chemosphere 39, 519-526. 

Occupational exposure to CDDs occurs primarily through inhalation and dermal contact of fire fighters and cleanup workers involved with transformers containing PCBs and polychlorobenzenes in workers involved in incineration operations in workers in metal reclamation facilities, and in workers producing and handling pesticides, hexachlorophene, trichlorophenol, or other chlorinated compounds (e g., pentachlorophenol) that may contain small impurities of 2,3,7,8-TCDD or other CDDs (Papke et al. 1992). In addition, these authors reported that the CDD/CDF homologue profiles in whole blood of workers engaged in a variety of different chemical processes or in occupational accidents exhibited distinct CDD/CDF patterns (Papke et al. 1992). 

Chlorinated Hydrocarbons Other Chlorinated Compounds. The substitution of chlorine atom for hydrogen in a compd greatly increases the anesthetic action of the derivative. In addn, the chlorine deriv is less specific than the parent hydrocarbon in its action, and may affect other tissues along with those of the central nervous system of this body. The chlorine deriv is generally quite toxic and may cause liver, heart Sc kidney damage. As a rule, unsaturated chlorine derivs are highly narcotic but less toxic than saturated derivs. Sax(Ref 4) has discussed in detail the toxicities Sc hazards of a number of chlorinated compds, including Chlorinated Diphenyls Chlorinated Hydrocarbons, Aromatic Aliphatic Chlorinated Naphthalenes Chlorinated Phenols Chlorinated Triphenyls others. 

Any compound that yields ions listed in Table 5 and also elutes within the retention time window of the corresponding homologue is a potential interference. PCDDs/PCDFs are often associated with other chlorinated compounds such as polychlorinated biphenyls (PCBs) and polychlorinated diphenyl ethers (PCDPEs). These compounds may be found at concentrations several orders of magnitude higher than that of the analytes of interest and may otherwise interfere with the analysis of PCDDs/PCDFs. Therefore the retention time of the target analytes must be verified using reference standards and compared to retention time... 

Trichlotoehtylene is a well-knovm pollutant. In aqueous systems this pollutant, like other chlorinated compounds such as chloroform, might be introduced into water following standard antibacterial treatment of drinking... 

A volatile chlorinated solvent that may be produced by the breakdown of other chlorinated compounds. It was one of the first anaesthetics, chronic (toxicity)... 

Unlike the case for other chlorinated compounds such as PCBs, double charged ions (at m/z values < MG/2 and with only 1 u between the chlorine isotope peaks) have not been mentioned for toxaphene components. The analysis of the GC/EI-MS fragmentation patterns allows a partial structure elucidation and the confirmation of the presence of a bornane skeleton. This knowledge facilitates a further structure elucidation by H-NMR spectroscopy [111]. 

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