The present work aimed to use a small volume of solvent for extraction of a large volume of urine sample in order to reduce the increase in hazardous waste. Sodium dodecyl sulfate (SDS) was found to exert an ability to repress gelatinization of solvent, which could be caused by shaking a small volume of solvent with a large volume of urine sample. Use of SDS provided the following simple method. Filtrate (100ml) of a human urine sample (pH 9-10 or 3-4) was spiked with 100μl of 5% SDS solution, and shaken with 2.5ml of chloroform. The clear, separated chloroform layer was dried in a glass tube (2ml), and the residue dissolved in solvent (chloroform : 50μl) and subjected to analysis. This characteristic behavior of SDS for separation of clear chloroform was interpreted by hypotheses deduced from chemical equilibria among SDS, protein, and chloroform.

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We examined the effect of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) on changes in gene expression of murine testicular Leydig TM3 cells by a method of differential mRNA display based on a PCR technique. Although no change in viable cell number was observed by TCDD at the concentration of 10nM, Ah receptor mRNA was down-regulated and CYP1A1 was induced in TM3 cells. One hundred and sixty-one PCR products, differentially expressed in 2% agarose gel electrophoresis after PCR amplification, were detected. Nine cDNAs were confirmed to be differentially expressed in Northern ELISA analysis. Two cDNAs were cloned and sequenced. One was identical to Homo sapiens Nedd-4-like ubiquitin-protein ligase WWP2 (WW domain-containing protein), which is associated with the ubiquitin proteolytic process. TCDD decreased expression of WWP2, which might cause the suppression of proteolytic process. The other was identical to the mouse expressed sequence tag. The function of this gene was not known. These genes might provide information for understanding TCDD-induced toxicity or biological responses.

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Involvement of renal γ-glutamyltranspeptidase (γ-GTP) in differences in the renal uptake of Hg²⁺ by male and female mice of various ages was examined using five strains of mice, namely, BALB/cA, C57BL/6N, CBA/JN, C3H/HeN and ICR. We observed strain-related and gender-related differences in the renal accumulation of Hg<2+> 30min after the administration of mercuric chloride (1μmol/kg, s.c.). Renal γ-GTP activity also varied among the tested strains, and the activity in males was about twice that in females. A significant correlation was recognized between renal γ-GTP activity and the renal accumulation of Hg<2+>. Both renal uptake of Hg<2+> and renal γ-GTP activity increased gradually with age in male ICR mice from 2 to 8 weeks after birth but remained relatively constant in ICR females. Significant gender-related differences in both renal accumulation of Hg<2+> and γ-GTP activity were observed 4 weeks after birth and thereafter. Castration of male ICR mice decreased both renal accumulation of Hg<2+> and γ-GTP activity to the levels in females. Injection of testosterone increased both renal accumulation of Hg<2+> and γ-GTP activity in castrated male mice and in normal female mice to the levels in control male mice. These results suggest that strain-related, gender-related and age-related differences in the renal accumulation of Hg<2+> in mice might be due to differences in renal γ-GTP activity and, furthermore, that renal γ-GTP activity might be controlled, at least to some extent, by testosterone.

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Intestinal flora plays important roles in the decomposition and excretion of organomercurial methylmercury, and these roles in decomposition and excretion of organomercurial phenylmercury were examined in mice given antibiotics orally. Female ICR mice were given antibiotic neomycin and chloramphenicol in drinking water for 2 d before phenylmercury administration in order to decrease intestinal flora, and the antibiotics were given throughout the experiment. Phenylmercuric acetate (2mg Hg/kg body weight) was administered to mice intraperitoneally, and feces and urine were collected daily for 4 d. Mice were sacrificed 5 d after phenylmercury administration. There were no differences between the control and the antibiotic-treated mice in the percentage of inorganic mercury to total mercury in feces, urine, liver or kidney. Total mercury excreted in feces and urine did not differ between the antibiotic-treated mice and the control mice. These results suggest that intestinal flora does not play a role in the decomposition and excretion of phenylmercury in mice.

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The effect of isoflavone-containing soybean extract (nijiru) administration on bone components in rats was investigated. Rats were orally administered nijiru solution (100mg/ml/100g body weight) twice a day for 7 and 14 d. Nijiru suspension contained saponin (66μg/ml), daidzin (77μg/ml), daidzein (0.6μg/ml), genistin (58μg/ml), and genistein (0.6μg/ml). The solution administered for both periods caused a significant elevation of calcium content, alkaline phosphatase activity, and deoxyribonucleic acid (DNA) content in the diaphyseal and metaphyseal tissues of the femur in rats, while administration for 14 d did not cause a significant alteration in body weight or serum calcium and inorganic phosphorus concentrations, indicating that the solution may not have a toxic effect. This study demonstrates that intake of isoflavone-containing nijiru has an anabolic effect on bone components in rats, suggesting its role in the prevention of osteoporosis.

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Linear alkylbenzenesulfonates (LAS) and alkylphenolpolyethoxylates (APE) are shown to belong to a major group of surfactant as ingredients of detergents and are normally present in raw sewage. Many biodegradation products of these surfactants, such as sulfophenyl-carboxylic acids, nonylphenol (NP) and nonylphenoldiethoxylate (NP2EO) etc., and LAS complexes (LAS-C) with cationic surfactants are also present in river water, sediment and/or effluent. Recently, the estrogenic properties of the biodegradation products of APE, NP and NP2EO etc., have a great interest for us. In order to assess the risks of LAS and APE for an aquatic environment, the following are required to be cleared ; (1) exposure concentrations of these compounds, including their biodegradation products and LAS-C, (2) behaviors on their biodegradation, adsorption, and the rate of removal in the wastewater treatment plant, (3) toxic and estrogenic effects on aquatic organisms and eosystem. In this review, the recent trends of studies on LAS, APE and their biodegradation products, and LAS-C are discussed.

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The recyclings of the waste is important for the control of discharging the waste. The effort of the waste-recycling began at various fields. The practice about heavy metals of mercury and cadmium was also started. The fluorescent light bulb and dry battery is the industry products containing heavy metals, such as mercury, manganese and zinc. In addition the waste water from the industry process is contaminated by a large armount of heavy metals. The objective of this paper is to introduce the outline of the collecting and recycling heavy metals from the fluorescent light bulb, dry battery and waste water in Japan.

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Steroids are transported in free forms and also in bound forms with β-globulin and/or with albumin in serum, and bind to with an intracellular specific 'receptor' protein after permeation through the cell membrane of target cell. Albumin and globulin cannot permeate through the cell membrane, so it has been generally assumed that the concentration of steroids in free forms determines the uptake rate and its bioavailability. In this report, the effects of the addition of such free fatty acids as palmitic acid, oleic acid and linoleic acid to the fractions of free β-estradiol and testosterone in serum were examined in vitro. It was found that the concentration of free steroids did not vary at the normal levels (when the range of the molar ratios of free fatty acid/albumin in serum was from 0.5 to 2) in men and women, but when the molar ratios of free fatty acid/albumin exceeded 3 the concentration of free steroids increased by the addition of free fatty acids. The effects of free fatty acids on the increase of the concentration of free steroids fraction were in the following order : linoleic acid, oleic acid > palmitic acid. These results suggest that the elevation of the concentration of free fatty acids in serum, amplified by high fat consumption, obesity and stress, may cause the increases of physiologically active β-estradiol and testosterone.

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An existence of 5-lipoxygenase in Gracilaria asiatica, a species of red algae causing deaths of three persons who ate cooked one in Japan, was confirmed using agonists and an antagonist. The involvement of the enzyme in food poisoning was also investigated. Leukotriene (LT) B₄, a stable metabolite of arachidonic acid (AA) catalyzed by 5-lipoxygenase, increased significantly in algae with putative stimuli, such as Ca ionophore A23187, Diamide and N-ethylmaleimide. The increase of LTB₄ by Diamide was inhibited significantly by AA861, a 5-lipoxygenase inhibitor. No change in concentrations of two isomers out of three, 6-trans -LTB₄ and 6-trans-12-epi-LTB₄, was observed when these stimuli were added. The other naturally existing isomer which possesses the same molecular weight as LTB₄, but not identified stereochemically, showed a synchronized change with LTB₄. The 5-lipoxygenase activity was lost by boiling raw algae for 10min or further incubating the heated algae for 1h at 37°C with 0.03N HCl (pH2). However, LTB₄ contents in the ethanol extracts from algae after these treatments increased significantly. These findings demonstrate that G. asiatica possesses an AA metabolic pathway via 5-lipoxygenase, but the enzyme activity would be lost by cooking, and also by ingesting in the stomach. The cortex of cooked algae would become soften in the stomach, resulting in the effective extraction of LTB₄ from algae in situ.

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The easy and quick determination method of aldehydes as hazardous air pollutants in indoor air by use of a passive tube packed with silica gel coated with O-(2, 3, 4, 5, 6-pentafluorobenzyl) hydroxylamine (PFBOA) was investigated. The analytical procedure consists of the following 3 steps : concentration and derivatization of aldehydes in sample air by the passive tube, desorption of PFBOA-derivatives of aldehydes from an adsorbent with cyclohexane and determination of PFBOA-derivatives of aldehydes by GC-MS analysis. The diffusive uptake rates of aldehydes were calculated using the obtained data from both active and passive tube methods applied to some newly-built ferroconcrete uninhabited houses and single family houses. The rates of formaldehyde and acetaldehyde were 1.983±0.254ml/min (n=25, R.S.D. 12.8%) and 1.690±0.373ml/min (n=24, R.S.D. 22.0%), respectively. The detection limit of formaldehyde in indoor air by the passive tube method was 0.0156mg/m³ for 24h air sampling, and that of acetaldehyde was 0.0382mg/m³. The PFBOA passive tube method was applied to the determination of aldehydes in newly-built ferroconcrete uninhabited houses, and sufficient results were obtained.

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