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Methoxychlor mixture

In a sensitive and specific colorimetric method 1,1,1-trichloro-2,2-bis(p-methoxyphenyl)-ethane is extracted from plant or animal tissue, using benzene or petroleum ether as the solvent. The solvent is evaporated at room temperature by a current of air and the residue dehydroha log ena ted with 2% alcoholic potassium hydroxide. By petroleum ether extraction the resulting 1,1-dichloro-2,2-bis(p-methoxyphenyl)-ethylene is removed from the reaction mixture. After the solvent is removed by air evaporation the dehydroha log ena ted methoxychlor is isolated from the nonsaponifiable portion of the fats and waxes by dissolving the residue in hot acetone, chilling, and filtering. After the acetone is removed by air evaporation, the residue is treated with 85% sulfuric acid. This produces a red solution with an absorption maximum at 555 m/z, the intensity of which can be read on a colorimeter and is a function of the methoxychlor concentration. Beer s law is obeyed over the range of 1 to 50 micrograms. [Pg.260]

Dehydrohalogenation is readily accomplished by heating with 2% potassium hydroxide in 95% ethyl alcohol. In order to separate the dehydrohalogenated methoxychlor from the reaction mixture, the alcohol is allowed to evaporate, and the residue is taken up in petroleum ether and washed with water. Most batches of even reagent grade petroleum ether contain substances which after contact with potassium hydroxide will yield... [Pg.261]

A large number of ubiquitous environmental pollutants are very toxic to the hypothalamic-pituitary-thyroid (HPT) axis when administered at high (greater than environmental) levels. To study low level effects on the HPT axis, laboratory animals were administered a mixture of 16 organochlorine pesticides and other chlorinated hydrocarbons and heavy metals, all at levels similar to those found environmentally, so as to simulate environmental exposure. The chemicals included DDT (6.91), HCB (5.73), TCDD (6.80), PCBs (6.29), methoxychlor (5.08), endosulfan (3.83), heptachlor (6.10), hexachlorocyclohexane (3.80), dieldrin (5.40), aldrin (6.50), mirex (7.18), several chlorinated benzenes (2.84-3.44), cadmium (-1.65), and lead (1.35). Effects were measured by monitoring thyroid activity. The study found that this mixture of environmental pollutants was toxic and can alter HPT physiology in sexually mature malesJ50 ... [Pg.224]

Further investigations revealed not only the presence of DDT and its metabolites in Teltow Canal sediments but also the occurrence of 2,4 and 4,4 -methoxychlor (MDT) at elevated concentrations (up to 1100 pg/kg) (22). As methoxychlor is structurally related to DDT, MDT-related compounds were also included in the quantitative analyses (see Tab. 6). We detected MDT, MDD, MDE, MDB and MDA in the extracts and partly in the hydrolysis product mixtures of all four sediment samples. The total amounts ranged between 600 and 8000 pg/kg in the extracts and between 1200 and 6000 pg/kg after application of the hydrolysis procedure. In degradation products after BBr3-treatment and RuC -oxidation no MDT-related substances were analysed likely due to the lower concentration level as compared to the DDT-related compounds. [Pg.280]

The chlorinated compounds should be completely separated in the order listed in Section 2, with heptachlor nearest the solvent front and dicofol closest to the origin. Other common organochlorine insecticides that can be detected and identified by this TLC procedure include aldrin, DDE, DDT, TDE (DDD), endrin, BHC, daconil, methoxychlor, captan, toxaphene, and chlordane. Alternative mobile phases that should be tested for any particular mixture not separated by hexane-acetone (99 1) include hexane (recommended for aldrin, heptachlor, p,p -DDE, o,p and p,p -DDT and p,p -TDE) benzene-hexane (1 1) and hexane-methanol (99 1) (applicable to more polar pesticides). [Pg.460]

Compound Name Methyl Acetate Propionic Acid Propionic Anhydride Methyl Mercaptan Dimethyl Sulfide Formic Acid Methyl Alcohol Hexamethylenetetramine Methoxychlor Methoxychlor Diethylebe Glycol Monomethyl Ether Methylacetylene-Propadiene Mixture Methylacetylene-Propadiene Mixture Crotonaldehyde Methyl Acrylate Methyl Formal Methyl Alcohol Methallyl Chloride Methylamine N-Methylaniline Methyl Amyl Acetate Methyl Amyl Alcohol Methyl Isobutyl Carbinol N-Amyl Methyl Ketone O-Toluidine 0-Toluidine N-Methylaniline N-Methylaniline Propyleneiniiine. [Pg.152]

Test compounds used in this study are shown in Figure 2. Methoxychlor (1) was obtained from Wako Pure Chemical Industries, Ltd. (Osaka, Japan). Synthesis of all other conqxrunds was previously rqwrted (7). No contaminants in tested conqtounds were observed by thin-4ayer chromatography. Conqxtunds were dissolved in dimethyl sulfoxide and diluted to 0.1 mM for the inhibition of ER binding assays (final concentration 38 pM). Metabolite mixtures of each test conqmund were obtained as follows. Each compound (final concentration 0.S > mM) was incubated for 60 min at 37 C with 5% rat liver S9 fraction (Kikkoman... [Pg.160]

S) k>ih>OH-MXC is predominandy formed by enzymatic 0-demethylation of methoxychlor using rat and human liver microsomes as previously described. Taking into account the result that (S)-mono-OH-MXC is 3 times more active than the (i ) enantiomer, the estrogenic activity of methoxychlor after metabolic activation in vivo should be higher than estimated from the in vitro study using racemic mixtures. [Pg.164]


See other pages where Methoxychlor mixture is mentioned: [Pg.50]    [Pg.264]    [Pg.201]    [Pg.368]    [Pg.1074]    [Pg.74]    [Pg.3002]    [Pg.169]    [Pg.230]    [Pg.765]    [Pg.192]    [Pg.498]    [Pg.159]    [Pg.160]    [Pg.161]    [Pg.155]    [Pg.316]   


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Methoxychlor

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