Benzene hexachloride See

Benzenediol, see Hydroquinone p-Benzenediol, see Hydroquinone Benzeneformic acid, see Benzoic acid Benzene hexachloride, see Lindane Benzene hexachloride-a-isomer, see a-BHC Benzene-crs-hexachloride, see p-BHC Benzene-y-hexachloride, see Lindane a-Benzene hexachloride, see a-BHC p-Benzene hexachloride, see p-BHC 6-Benzene hexachloride, see 8-BHC y-Benzene hexachloride, see Lindane frans-a-Benzene hexachloride, see p-BHC Benzene hexahydride, see Cyclohexane Benzene methanoic acid, see Benzoic acid Benzene methanol, see Benzyl alcohol Benzene tetrahydride, see Cyclohexene Benzenol, see Phenol... 

BENZENEFORMIC ACID see BCL750 BENZENE HEXACHLORIDE see BBP750... 

Benzenedicarboxylic acid dimethyl ester, see Dimethyl phthalate Benzene hexachloride, see Lindane Benzene-cw-hexachloride, see 3-BHC... 

In earlier editions of the Eniyclopedia there have been articles covering the properties, manufacture, capacities, etc, of polychlorinated biphenyls (PCBs), chlorinated naphthalenes, benzene hexachloride, and chlorinated derivatives of cyclopentadiene. These materials are no longer in commercial use because of their toxicity. However, they stiU impact on the chemical industry because of residual environmental problems. Their toxicity and environmental impact are discussed (see Cm.OROCARBONSANDCm.OROHYDROCARBONS, TOXIC aromatics). 

As seen from the structural formulas in Figure 16.4, the organochlorine insecticides are of intermediate molecular mass and contain at least one aromatic or nonaromatic ring. They can be placed in four major chemical classes. The first of these consists of the chloroethylene derivatives, of which DDT and methoxychlor are the prime examples. The second major class is composed of chlorinated cyclodiene compounds, including aldrin, dieldrin, and heptachlor. The most highly chlorinated members of this class, such as chloredecone, are manufactured from hexachlorocyclo-pentadiene (see Section 16.3). The benzene hexachloride stereoisomers make up a third class of organochlorine insecticides, and the third group, known collectively as toxaphene, constitutes a fourth. 

A mixture of the several isomers of 1,2,3,4,5,6-hexachlorocyclo-hexane it contains not less than 12% of the gamma isomer. Benzene hexachloride has five known isomers designated alpha, beta, gamma, delta, and epsilon of these only the gamma isomer (see Lindane) is outstandingly active as an insecticide. 

SAFETY PROFILE Confirmed carcinogen with experimental carcinogenic, tumorigenic, and neoplastigenic data. Poison by ingestion. Mutation data reported. When heated to decomposition it emits toxic fumes of Cr. See also BENZENE HEXACHLORIDE and other benzenehexachloride entries. 

CONSENSUS REPORTS lARC Cancer Review Animal Sufficient Evidence IMEMDT 5,47,74 IMEMDT 20,195,79. SAFETY PROFILE Confirmed carcinogen with experimental tumorigenic and neoplastigenic data. Poison by inhalation and ingestion. Human systemic effects by an unspecified route convulsions. Potentially dangerous reaction with DMF in presence of Fe, also CCU. When heated to decomposition it emits highly toxic fumes of cr, HCl, and phosgene. See also BENZENE HEXACHLORIDE and other benzenehexachloride entries. 

See also Aflatoxin Algae Ammonia Asbestos Benzene Hexachloride, Mixed Isomers Brodifacoum Carbamate Pesticides Carbon Monoxide Castor Bean Copper Coumarins DDT (Dichlorodiphenyltrichloroethane) DEET (Diethyltoluamide) Dichlorvos Dieldrin Ethylene Glycol Hydrogen Sulfide Lead Malathion Methane Molybdenum Mushrooms, Coprine Mushrooms, Cyclopeptide Mycotoxins Nitrites Oleander Organochlorine Insecticides Organophosphates Paraquat Parathion Pyrethrins/Pyrethroids Selenium Sodium Strychnine Sulfur Dioxide Thallium Warfarin. 

Design a 250,000 Ib/yr Lindane (99 per cent 7 isomer of benzene hexachloride) plant based on process information given in the current literature [e.g., see Chem. Eng. Progr., 52 281 (1956) Chem, Week, 78 54 (1956) Ind. Eng. CAem., 48(10) 41A (1956)], Develop the process flow. sheets, equipment specifications, and plant layout. Examine the economics of producing Lindane including (1) fixed and capital cost estimates by one or more of the methods outlined in Chap. 6, (2) profitability analysis showing return on investment and pay-out time, (3) break-even point analysis of the project, (4) economic estimates for a plant producing 500,000 Ib/yr and 750,000 Ib/yr. 

The remaining examples of the ElcB reaction which lead to olefin products are supported by less sound evidence. To explain the abnormal stereochemistry of a beta-elimination, the ElcB mechanism has often been invoked rather than the E2 mechanism, the classic example being the base induced dehydrochlorination of /3-benzene hexachloride in which all the adjacent chlorine atoms are situated trans to each other . Stereochemical evidence alone is insufficient proof of the carbanion mechanism this aspect is discussed more fully elsewhere (see Section 2.3). 

Benzene, 1-fluoro-2,4-dinitro-. See 2,4-Dinitrofluorobenzene Benzene formic acid. See Benzoic acid Benzene hexachloride y-Benzene hexachloride Benzene hexachloride, all isomers. See Lindane... 

BENZENE HEXACHLORIDE. C,H,CI,. Aluminum alloy equipment has been used in handling benzene hexachloiide. CAUTION see "Halogenated Hydrocarbons." See also Ref (3) p. 110, (7) p. 31. 

Benzene in kerosene - 47, 160 Benzene in methanol - 285 Benzene carbinol -823 Benzene carboxylic acid (see Benzoic acid) Benzenedisulfonic acid - 108, 156,184 Benzene hexachloride (Lindane) - 34, 229, 478,613, 658... 

The Food and Agriculture Organization of the United Nations has recommended methods for the determination of mercury in pesticides. The method selected depends on the other constituents of the formulation and in the presence of copper the method of Brookes and Solomon (see p. 419) is most suitable. In the presence of most other constituents the selected method is one in which the sample is refluxed with concentrated sulphuric acid and potassium nitrate before determining the mercury volumetrically with thiocyanate. When large amounts of calcium carbonate or highly chlorinated compounds e,g, benzene hexachloride) are present, the mercury is isolated as a sulphide before conversion to the ionic form with strong acid. 

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