Many analytical methods for polychlorinated dibenzo-p-dioxins (PCDD) from municipal incinerators by gas chromatography (GC)/mass spectrometry (MS) were reviewed. Efficiency of separation of the samples from incinerators, extraction of PCDD from the samples, clean-up procedures of the extracts and GC/MS on the determination of PCDD, and analytical systems for PCDD especially 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin were described.

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A method for the determination of low levels (∼10^-11g/l) of benzo (α) pyrene (BaP) in raw water of water supply was studied. The water samples (1 or 31) were collected into a silanized erlenmeyer flask. Five g of Amberlite XAD-4 resin was added to the flask and mixed with magnetic stirrer for 5 h at 20°C in the dark. After the resin was filtered by a water aspirator, the resin was oven-dried at 50°C for 16 h. The resin was shaken with 20 ml of elution solvent, a mixture of ethanol and benzene (1 : 9, v/v), for 10 min by an ultrasonificator. The resin and the solvent were transferred to a 80 ml filter-funnel, and then the sorbed BaP on the resin was eluted with 100 ml of the elution solvent. The eluate was evaporated to dryness under a reduced pressure. The residual was dissolved in 0.5 ml of benzene. BaP in the benzene solution was separated by a one dimensional dual band thin-layer chromatography. The spots of BaP on the plate were scraped off into a small centrifugal tube. After adding 2 ml of dimethylsulfoxide (DMSO) into the tube, ultrasonic extraction was carried out for 10 min in order to dissolve BaP completely. The DMSO solution was centrifuged for 5 min, and then the supernatant was used for the identification and determination of BaP by a derivative spectrofluorometry. The determination was carried out under the following instrumental conditions ; excitation wavelength : 369 nm, slit 16 nm, emission wavelength : 380 nm scanning, slit 3.5 nm, order of derivative : 4-th, increment in differentiation : 3 nm, scanning speed : 60 nm/min. The recoveries by the presented method were at the 0.54 and 1.08 ng/l spiking levels of 11 distilled water for 85.6±4.5% and 84.2±3.7%, and at the 0.73 ng/l spiking levels of 31 real water sample for 82.2-97.3%, respectively. The sorbed BaP onto the resin was stable at 4°C or 20°C in the dark during 30 days. The losses of BaP by adsorption onto the inner walls of the erlenmeyer flask were 7% or less. When the determination of the concentration of BaP by this method was carried out, the lower limit of detection for 3 l water samples was 0.03 ng/l at the peak height of 2.5% levels of full-scale range. The concentrations of BaP in 6 ground water samples and 3 river water samples were determined by this method. It was confirmed that the concentrations in raw water of water supply were very small, ranging 0.05-0.15 ng/l.

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Carp (Cyprinus carpio) were injected intraperitoneally with 2 mg Cd/kg body weight as CdCl₂ solution. Two types of isometallothioneins were separated from carp kidney by successive treatment with homogenization, ultracentrifugation, incubation, centrifugation, gel filtration and ion exchange chromatography. Purity was shown by polyacrylamide DISC-gel electrophoresis. The molecular weight of native metallothionein-I and -II was found to be 12000-13000. The disappearance of Cd-mercaptide bond was estimated under acidic conditions. Cysteic residues were about 30% in kidney isometallothioneins, Gly and Lys were high, but no aromatic amino acids or His residues were detected. In a double diffusion test, spur formation was shown between two hepato-pancreatic isometallothioneins, and also between hepato-pancreatic metallothionein-II and kidney metallothionein-II.

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Antioxidants in 37 different brands of commercially available rubber gloves mainly for domestic use were analysed by the method previously reported (M. Kaniwa, S. Kojima, A. Nakamura, M. Ishihara, Eisei Kagaku, 28, 137 (1982)). It was clarified that almost every brand of the domestic gloves contained one or two of the following phenolic antioxidants : 2, 2'-methylene-bis (4-methyl-6-tert-butylphenol) (MBMBP), styrenated phenol (SP), 2, 2'-isobutylidene-bis (4, 6-dimethylphenol) (IBBDMP), 4, 4'-butylidene-bis (3-methyl-6-tert-butylphenol) (BBMBP). A nitrogen-containing antioxidant, N-isopropyl-N'-phenyl-p-phenyl-enediamine (IPPD), known as a strong sensitizer, was detected in one brand of gloves for industrial use. The frequencies of detection of the antioxidants were as follows : MBMBP, 19/37 ; SP, 8/37 ; IBBDMP, 6/37 ; BBMBP, 1/37 ; IPPD, 1/37. Patch testing to various antioxidants was also studied in 40 patients with allergic contact dermatitis from rubber or poly (vinyl chloride) materials. No one reacted to the phenolic antioxidants tested, including MBMBP and SP. On the other hand, about one third of the patients reacted to IPPD. From the results, it is preferred to use the phenolic antioxidants for not only domestic but also industrial rubber gloves.

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A simple and reproducible method for the determination of residual tetracyclines (TCs) in livestock products by high-performance liquid chromatography was established. Tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC) in a sample were extracted with 5% aquous perchloric acid. The extract was passed through SEP-PAK C₁₈ cartridge. After washing the cartridge with water, TCs was eluted with a mixture of N, N-dimethylformamide (DMF)-water (4 : 6) containing 0.02 M phosphoric acid. The eluate was injected on a Li Chrosorb RP-8 column by using a mixture of DMF-water (1 : 4) containing 0.02M phosphoric acid as a mobile phase. The effluent was monitored with a UV detector at a wavelength of 340 nm. The recoveries of TCs from cattle muscle, liver, kidney and milk fortified with 1μg/g of TC and OTC and 2μg/g of CTC were 34.7-52.9% for muscle, 37.7-51.6% for liver, 53.1-68.3% for kidney and 74.8-88.7% for milk, respectively. The quantitative analysis was carried out by the method of standard addition and the minimum detectable amount of TC and OTC was 0.1 ppm and CTC was 0.2 ppm.

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A procedure is described for the determination of guaiazulene (GA) in cosmetics by high performance liquid chromatography (HPLC). The sample was mixed with Cellite, transfered to a chromatographic column, and eluted with acetonitrile. The acetonitrile was added to water, and liquid-liquid partition between hexane. The hexane was concentrated and then GA was determined by HPLC on octadecylsilated silica column using a mobile phase of methanol-water (9 : 1, v/v), UV detector (284 nm) and fluorescence spectrophotometric detector (FD) (Ex·λ : 285 nm, Em·λ : 390 nm) for detection. As a result, the calibration curve was linear in the range 1-10 μg/ml of GA on FD and UV detector. Recoveries of GA obtained from a variety of cosmetic samples spiked at 50 and 100 ppm levels were 93.8-97.2% and 94.8-97.0%, respectively. When this method was applied to the analysis of GA in commercial samples, GA could be determined without the influence of obstructive substances.

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CODMn of fatty acids is fundamentally important because various materials will produce fatty acids as the results of COD treatment. In acidic method, formic acid consumed oxygen up to 29.3% of theoretical value, but catalytic effect of AgNO₈ was not recognized. The other fatty acids indicated a very promoting effect of the addition of AgNO₃ to thier oxygen consumption. In alkaline method, formic acid consumed oxygen up to nearly 100%, but lower carbon chain fatty acids, from acetic acid to valeric acid, showed no COD values. COD values of longer carbon chain fatty acids a little increased with an increase in the carbon number. As the reaction products of these acids, fatty acids of reduced carbon number, one after another, were determined with GC and GC-MS. On pivalic acid, tert-C₅-acid, an increase in acidic COD value was rather recognized, but the BOD value was much diminished. BOD values of the other fatty acids were considerably high and attention will be necessary when lower COD values of acidic method were estimated. Very lower COD value of alkaline method compared with the BOD values will be better to be avoided.

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Formaldehyde and its metabolite, methanol, in the blood were determined by gas-liquid chromatography (GC) with a hydrogen flame ionization detector on 2.0 m glass column packed with 25% PEG 1000+2% KOH at 80°C. Formaldehyde and methanol in the blood sample were measured by head space gas method. n-Propanol as an internal standard was added to a vial containing the blood sample. The calibration curves of formaldehyde (0.2-1.2 mg/ml) and methanol (0.2-1.0 mg/ml) both showed a straight line. Recovery rates of formaldehyde added to the blood at various concentrations were 96.7±3.9% at 0.4 mg/ml, 97.7±2.7% at 0.8 mg/ml and 98.0±3.3% at 1.2 mg/ml. And recovery rates of methanol were 97.6±1.8% at 0.4 mg/ml, 97.6±0.7% at 0.6 mg/ml and 99.0±0.7% at 1.0 mg/ml. The contents of formaldehyde and methanol detected in the blood of the suicide were 0.773 mg/ml and 0.574 mg/ml respectively. Formaldehyde was identified as formaldehyde-2, 4-dinitrophenylhydrazone by GC-chemical-ionization mass spectrometry (CI-MS). Formic acid was determined by ion chromatography. The blood sample was diluted to 20 fold with water and the sample solution was injected into the chromatograph equipped with a SAX-251 column (250 mm) connected with a PAX-051 column (50 mm) as a pre column. Mobile phase was 10 mM Na₂B₄O₇ solution. The content of formic acid detected in the blood of the suicide was 78μg/ml.

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