The present review deals with metabolism of the vinyl side chain and the benzene nucleus of the plastic monomer, styrene, in vitro and in vivo in relation to mutagenicity and carcinogenicity exerted by its reactive metabolic intermediates, phenyloxiran, 1-vinylbenzene 1, 2-oxide and 3, 4-oxide. Phenyloxiran plays an important role as an intermediate in the vinyl side chain oxidation to phenylethanediol, mandelic acid, phenylglyoxylic acid, benzoic acid, hippuric acid, mercapturic acids and phenylacetic acid. The mercapturic acids are directly correlated with the regioisomeric glutathione conjugates of phenyloxiran. Stereochemistry in the formation, hydrolysis, and GSH-conjugation of phenyloxiran has very recently established in relation to enantioselectivity and regioselectivity of the enzymaticre actions. 1-Vinylbenzene 1, 2- and 3, 4-oxides, new candidates for reactive intermediates of styrene, are specific precursors of 2- and 4-vinylphenols, respectively, in vivo and in vitro and have potent mutagenicity at very low concentrations toward Salmonella typhimurium TA 100 but not toward the TA 98 strain bacteria. Data strongly suggest the vinylbenzene oxides play more important roles in the mutagenicity of styrene in the presence of a metabolic activation system.

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Research on xenobiotics metabolism in aquatic organisms was initiated from the view point of comparative biochemistry and physiology with mammalian species in the latter half of 1960's decade. Recently, it was drawn much attentions from the pollution aspects on both environmental fate and ecotoxicology of chemical substances. This review is described on the oxidative biotransformation of xenobiotics in fish liver mainly focusing on the role of hepatic cytochrome P-450 dependent mixed function oxidase system. Whereas fish is situated in the top of the trophic level of aquatic ecosystem and also important protein sources for human being. Many literatures demonstrated the presense of environmental contaminants having inducibility of the mixed function oxidase system in a wide variety of fish species. Also, some works on the metabolism of diisopropylnaphthalene (a substitute of PCBs for carbonless paper solvent) are introduced briefly.

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Separation and determination of twenty kinds of cosmetic azo dyes permitted in Japan were studied by reversed-phase high performance liquid chromatography. For identification and determination of the tested dyes, the system of Nucleosil 5C₁₈ column and acidic mobile phase was very useful. The used mobile phases were CH₃CN-THF-H₂O (pH 3.2, H₃PO₄) for oil-soluble dyes, and CH₃CN-THF-H₂O (pH2.0, HClO₄) for water-soluble dyes, Ca-lakes and Ba-lakes, respectively. This method was applied on 93 samples of commercial cosmetic azo dyes for the determination of "pure dye content." Data obtained by this method agreed well with those by the recommended official methods such as titanous chloride titration and spectrophotometric determination. Comparing with the official method, advantage of this method was to prevent the influences of contaminated other dyes, subsidiary dyes and impurities.

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Five kinds of aniline derivatives were chosen and subjected to LC₅₀ test using both static and flow water systems. The flow water system was more appropriate than the static one for volatile compounds, because 37% of N, N-dimethyl aniline in the test solution was lost during LC₅₀ test for 48 h. N-Methyl aniline, N, N-dimethyl aniline and 2, 6-xylidine were found to turn fish sideways producing syncope, and the states were observed during the test for 48h. Median syncopic concentration ; SC₅₀ values of aniline derivatives for 48 h were determined and compared with LC₅₀ values. Large differences were observed between SC₅₀ and LC₅₀ values in N, N-dimethyl aniline and 2, 6-xylidine. A rapid determination method of aniline derivatives in fish (killifish, gold fish and carp) using FTD-GC was developed and excretion of aniline derivatives accumulated in fish were determined. All compounds except N, N-dimethyl aniline were excreted within 4 h from fish body.

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The accumulation amounts of 5 aniline derivatives in killifish, gold fish and carp were determined in connection with their syncopic effect. In the case of aniline and o-toluidine, their amounts in fish increased proportionally to the concentration of the compounds in test solution, and the amounts gradually increased after the death of fish. On the contrary, the amounts stayed at constant level and syncopic states were observed for 48 h when 2, 6-xylidine, N-methyl aniline and N, N-dimethyl aniline were used, indicating the presence of threshold. Partition coefficient of aniline derivatives between n-octanol and water corresponded obviously to the amount of the compounds accumulated in fish body, but the relationship between partition coefficient and LC₅₀ or SC₅₀ values was not observed. It was considered from these results that syncopic state of fish may be a kind of selfguard action to prevent the accumulation of toxic compounds into their body.

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Tropaeoline 00 anion was found to be extracted with morphine benzyl derivative as 1 : 1 complex in dichloromethane. The tropaeoline 00-dichloromethane-hydrochloric acid system gave a red color for morphine benzyl derivative, while in the absence of hydrochloric acid, a dichloromethane phase showed a yellow color. In this way, the spectrophotometric method was investigated for the determination of a small amount of morphine by solvent extraction. The recommended procedure is as follows. One ml of standard morphine hydrochloride solution (1.30×10^-8-1.60×10^-7mol/ml), 5ml of 3% sodium carbonate solution, 2 ml of solution of benzyl chloride (2.75×10²μg/ml, 2.17×10^-6mol/ml) in acetone, and 5 ml of acetone were taken into a 20 ml Erlenmeyer's flask, Refluxed on a water-bath for 15 min and acetone was evaporated. After cooling, the flask was shaken for 30 sec with 10 ml of dichloromethane. After separation of the two layers, take 5 ml of dichloromethane layer was taken into 10 ml of test tube and added 1 ml of solution of tropaeoline 00 (1.22mg/ml) and 2 ml of buffer solution (pH 3.5). The mixture was shaken for 3 min and centrifuged for 2 min at 3000 rpm. Two ml of dichloromethane layer was taken into a glass tube and added 0.5 ml of 10 % hydrochloric acid in methanol, the absorbance of the solution was measured at 543 nm using dichloromethane as a reference. The morphine is determined by measuring the absorbance of the extracts over a range from 1.30×10^-8-1.60×10^-7mol/ml (5-60μg/ml) at 543 nm. The determination of morphine is not interfered by the presence of the additive materials, such as metal ions, ammonium ion, glucose, lactose and L-leucine. But a small amounts of alkaloids gave a strong interference.

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A rapid and reproducible method for the determination of saccharin (SA), benzoic acid (BA) and sorbic acid (SOA) by high-performance liquid chromatography (HPLC) was established. Ion pair partition system was used for both HPLC separation and sample clean-up. Liquid foods such as soy sauce, soft drinks and lactic acid bacteria beverages were diluted to suitable concentration with water. Hydrochloric acid (1N) and 0.005M cetyltrimethylammonium chloride were added to the dilute sample and the solution passed through SEP-PAK C₁₈ cartridge. After washing the cartridge with water, the three compounds were eluted with a mixture of methanol-0.05M phosphate buffer pH 5.0 (6 : 4). The eluate was diluted with water and 0.05M tetra n-butylammonium bromide (TBA) and injected on a Li Chrosorb RP-18 column by using a mixture of methanol-0.03M phosphate buffer pH 5.0 (7 : 13) containing 0.005M TBA as a mobile phase. The effluent was monitored with a UV detector at a wavelength of 225 nm. The recoveries of SA, BA and SOA from the samples fortified with 0.05g/kg each were 98.0-101.7%, 98.2-101.0% and 94.2-101.0%, respectively. These detection limits were 0.0005g/kg each.

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The cytotoxicity and metabolism of four butyltin compounds were examined on isolated viable rat hepatocytes. Of the compounds tested, tributyltin exhibited the most potent cytotoxicity and was metabolized with the fastest rate by rat hepatocytes. These actions of tributyltin would be due to the high affinity for rat hepatocyte. The formation of dibutyltin, monobutyltin and inorganic tin as metabolites of tributyltin was observed. However, in the case of tetrabutyltin, detectable metabolite was only monobutyltin. Cytochrome P-450 associated with the metabolism of butyltin compounds was induced by phenobarbital, but not by 3-methylcholanthrene. No metabolism of tributyltin was detected in isolated viable rat kidney cells. Therefore, it would be suggested that the contribution of liver was much larger than that of kidney on the metabolism of butyltin compounds in vivo.

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In order to investigate the role of metallothionein in acute cadmium (Cd) toxicity, the following results were obtained by administrating cycloheximide to mice. 1) The concentration of metallothionein in the liver of mice to which Cd and cycloheximide were administered decreased more than that given only Cd. 2) Metallothionein did not take part in the incorporation of Cd into the liver. 3) The rate of death in the mice to which Cd and cycloheximide were administered increased. 4) The concentration of metallothionein in the liver of mice given Cd and cycloheximide decreased with an increase in the amount of Cd administered. 5) After metallothionein was induced by Cd, the concentration of metallothionein in the liver of the group given cycloheximide was higher than that of the group to which no cycloheximide was administered.

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For the identification and quantitative analysis of methamphetamine and its metabolites in the urine from a habitual user of the stimulant, the combined method of gas chromatography and mass fragmentgraphy was developed. The proportion of methamphetamine and its metabolites to the excreted matter is as follows : amphetamine 7.5%, p-hydroxymethamphetamine 6.45%, p-hydroxyamphetamine 0.35%, and norephedrine 0.23% respectively.

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Combined method of the extraction of borate with 2-ethyl-1, 3-hexanediol (EHD)/CHCl₃ solution, and the color development by use of protonated curcumin was successfuly applied to the determination of borate in food. Conditions obtain low blank value, reliability and reproducibility were examined, and the following procedure was established. Solid sample was pretreated with dryashing method. The sample solution was acidified and extracted with 10% EHD solution. In the case of aqueous sample, the sample was acidified and extracted with the EHD solution dircetly. To an 1 ml aliquot of the EHD extract, 1 ml of 0.1% curcumin/acetic acid solution and 0.5 ml of concentrated sulfuric acid were added. The reaction mixture was allowed to stand for 30 min at room temperature. The curcumin was protonated and allowed to react with boric acid in this period. Then, ethanol (25ml) was added to the reaction mixture to decompose the excess protonated curcumin, and the absorbance of resulting solution was measured at 550 nm. Common ions other than fluoride ion did not interfere. The interference from fluoride ion up to 100μg/ml was negligible in this extraction. When the presence of large amounts of fluoride ion, the addition of lanthanum ion was more effective than that of zirconium ion for the masking of fluoride ion.

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We studied whether gas chromatographic method reported by Toyoda et al. for the analysis of general foods was also applicable to the analysis of tertiary-butylhydroquinone (TBHQ) in dairy products. That this method was revealed to be applicable to the analysis of dairy products, except for the use of OV-210 column instead of DEGS column, which required about 1/3 less time for the analysis. The recovery rates of TBHQ from various dairy products under the above conditions was 77-95%, and the limit of detection was about 0.01g/kg. The method also extracted portions of BHT, BHA, SoA and DHA used as food additives in dairy products, separately from TBHQ and therefore they were quite distinguishable. We also applied this method to 160 samples of dairy products available in the market (14 samples of processed cheese, 116 of natural cheese, 13 of butter and 17 of products containing milk and dairy products as their main ingredients), but TBHQ was not detected in any of the samples.

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