Chronic diseases such as allergy, cancer, thrombotic diseases and aging are expected to predominate in the 21st century. Prevention rather than treatment is important for these diseases, because highly selective and effective drugs such as antibiotics for pathogenic bacteria may not be easily developed. However, raising ω3/ω6 ratios of dietary oils has been found to be beneficial for the prevention of these diseases in animals, which has been supported by epidemiological studies in humans. Other food constituents and folk medicines have also been studied extensively for the effectiveness in the prevention of chronic diseases, and "physiologically functional foods" are going to be authorized in Japan. In view of a rapid progress in the development of new types of foods designed for specified chronic diseases, I emphasize the importance of "Preventive and Convalescent Pharmacy" in the medical-care required in the coming century in Japan.

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Several genera of fungi belonging to Aspergillus, Penicillium, Fusarium, Alternaria and others produce toxic secondary metabolites, so-called mycotoxins such as aflatoxins, sterigmatocystin, ochratoxins, trichothecenes, zearalenone and fumonisins. Some of these toxic compounds are detected in foods and animal feeds, causing food-born intoxication in man and livestocks. Current molecular epidemiology has demonstrated a close association between the exposure of these mycotoxins and human diseases, particularly of hepatic, renal and esophageal cancers in endemic areas. Newly isolated mycotoxins, fumonisins, and the trichothecene, nivalenol, are defined as a tumor promoter. Recent advances on ELISA methods are presenting the information on human exposure to aflatoxin B₁ (AFB₁) and ochratoxin A (OTA). The adducts of AFB₁ with serum albumin and hepatic DNA and the urinary metabolites such as AFP₁ and AFB₁-guanine adduct are expected as an excellent biomaker for AFB₁ exposure. On the basis of the toxicological and epidemiological surveys, the risk assessment is performed for AFB₁, OTA and zearelenone. To minimize the human hazards derived from the mycotoxins as environmental contaminants, the maximum tolerable limits for aflatoxins, trichothecenes and ochratoxins in foods and feeds are regulated in the most countries.

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Coffee produced mutagenicity on Salmonella typhimurium TA98 and TA100 without metabolic activation on treatment with nitrite under mildly acidic conditions. The mutagenicity of one cup of instant coffee (1 g of coffee powder in 100 ml of water) treated with 10 mmol nitrite at pH 3 and 37°C for 1 h was estimated to be 3.2 and 8.8×10⁴ His⁺ revertant colonies/plate for TA98 and TA100, respectively. The major mutagen (s) were partially purified by extraction with chloroform and adsorption to blue cotton. The mutagen (s) were separated by high performance liquid chromatography using reverse phase columns, and a mutagenic fraction with a single sharp ultraviolet-absorbing peak was obtained. His⁺ revertant colonies of this fraction per cup of instant coffee equivalent was 488 on TA98 and 300 on TA100 without metabolic activation.

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The lethal effect of bis (tri-n-butyltin [IV]) oxide (TBTO) on the halotolerant Brevibacterium sp. was examined as a function of NaCl concentrations added externally. More than 99.9% of the viable cells were killed after 20 min exposure to 20 μM TBTO in the absence of NaCl. In the presence of NaCl, however, the viability was greatly increased, i.e., about 1% of the cells survived in the presence of 0.5 M NaCl even after 8 h exposure to TBTO. Maximal survival (7.6%) was observed in the presence of 1.8 M NaCl. These results suggest that the lethal effect of TBTO on Brevibacterium sp. was efficiently reduced by NaCl. Reductive ability of other salts on TBTO was examined in the same manner, and the lethal effect of TBTO was decreased in the order : NaCl > KCl > NaNO₃ > NaSCN. This indicated that Cl^- as well as Na⁺ has the most protective action against TBTO lethality. The addition of TBTO caused the release of Na⁺ ion from the cells. Increase of the percentage of survival was connected with the decrease of Na⁺ efflux from the cells, indicating that the efflux of Na⁺ is an important factor in the viability of Brevibacterium sp.

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The kinetics of monochlorodimedone (MCD) chlorination with sodium hypochlorite (NaOCl), chloroisocyanurates (2Cl-and 3Cl-ICA), N-chlorosuccinimide (Cl-succinimide), and chloramine T and B were studied. The chlorination of MCD was recognized by a decrease in absorbance at 290 nm and at pH 7. Instantaneous chlorinations occurred with NaOCl and chloroisocyanurates. The rate constants for the chlorination with Cl-succinimide and chloramine T and B were determined. The reactions were determined to be second order-first order in each reactant, and were dependent on temperature. The observed second order rate constants at 15°C for Cl-succinimide, and at 25°C for chloramine T and B were 1500, 61.8 and 41.5 M^-1·S^-1, respectively.

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In this paper, the influences of incubation temperature on the production of earthy-musty odour substances and their growth were investigated using three Actinomycetes ; Streptomyces griseofuscus Mikawa A strain, S. griseofuscus IFO 12870 strain and S. resistomyciticus var. Biwako B strain. In the temperature range of 20-37°C Mikawa A strain produced continuously a large amount of 2-methylisoborneol (2-MIB) and geosmin at lower temperature. On the other hand S. griseofuscus IFO 12870 strain produced abundantly 2-MIB and geosmin at both low and high temperatures. S. resistomyciticus var. Biwako B strain produced a small amount of both substances compared with Mikawa A strain and IFO 12870 strain, but the effect of incubation temperature was small. The optimum temperature for the Actinomycete growth by M agar plate culture was higher for IFO 12870 strain and Biwako B strain than for Mikawa A strain. When using liquid culture it was higher for Mikawa A strain and IFO 12870 strain than for Biwako B strain. These results suggest that the amount of biosynthesis of protein enzymes related to earthymusty odour production is dependent on the incubation temperature like many other antibiotics. The optimum temperature for the earthy-musty odour production is lower than the optimum temperature for their growth. The optimum temperatures for several earthy-musty odour productions are not always the same even for the same kind of germs collected from different plates.

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Multivariate analysis was applied to the determination of a mixed organic compound by Fourier transform infrared spectroscopy (FT-IR) and each component was measured accurately without pretreatment such as separation procedure or addition of internal standard substance. For example, the mixture of tetracaine hydrochloride and glucose or methamphetamine hydrochloride and ephedrine hydrochloride (known blend composition) was measured by FT-IR. The obtained spectra were expressed by relative values to provide a data base. A mixture with unknown blend composition ratio (unknown sample) was dealt with in a similar manner. The obtained data were used for the multivariate analysis such as quantification IV, cluster analysis, cluster analysis from deviation and principal component analysis. The rough blend composition ratio of unknown sample was estimated and the data base for calibration curve was selected. Furthermore, the blend composition ratio was determined more accurately by the principal component scores.

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By the use of capillary gas chromatograph with flame photometric detection, di-n-butyltin (DBT) and mono-n-butyltin (MBT) compounds in the fetus, placenta, maternal liver, kidney, spleen, and thymus from pregnant Wistar rats were determined on day 18 of gestation after oral treatment with di-n-butyltin diacetate at doses of 0, 1.7, 5.0 or 15.0 mg/kg/day on days 7 to 17 of gestation. Treatment with DBT caused malformations such as cleft mandible, cleft lower lip, ankyloglossia, schistoglossia. Concentrations of DBT and its metabolite MBT increased in the fetus and placenta and the maternal organs in a dose-dependent manner. DBT and MBT concentrations in the fetus and placenta were less than those in the maternal tissues. DBT was high in the liver and kidney and MBT was high in the kidney and thymus. It is clear that DBT given to pregnant rats can be transferred to fetuses via placenta.

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Tyrosinase inhibitory action (TIA) of cosmetic raw materials containing cosmetic whitening ingredients was measured as an in vitro screening procedure. Among them, L-ascorbic acid phosphate magnesium salt (VC-PMg) had no TIA. The decomposition of VC-PMg was also examined by acid-phosphatase (Acp), a skin enzyme. Consequently, VC-PMg was hydrolyzed to L-ascorbic acid by pseudo first order reaction. The reaction solution containing L-ascorbic acid had TIA. The whitening effects of several cosmetic raw materials could be compared by the in vitro TIA test.

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It is known that the major products in the pyrolysis of cellulose can not be detected by gas chromatography because of their low volatility. Hence it has been difficult to analyze a slight amount of cotton composed of cellulose by pyrolysis-gas chromatography (PyGC). In our study, acid-catalyzed pyrolysis was applied to forensic discrimination of cotton and its blended yarn by PyGC. Fibers were pyrolyzed using a Curie-point pyrolyzer, attached to gas chromatograph or gas chromatograph-mass spectrometer under the conditions by the addition of hydrochloric acid or phosphoric acid. The presence of acid during pyrolysis provided an increase of volatile products such as furfural, and elevated detection limit of the fibers by PyGC in comparison with the conventional methods. When 10% of hydrochloric acid or 20% of phosphoric acid was added, more furfural was detected. This method made it possible to analyze a slight amount of cotton and its blended yarn by PyGC.

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The nephrotoxicity of cadmium (Cd) and mercury (Hg) in an acute exposure were compared by injecting both metals intravenously with DL-penicillamine (Pen) into mice. The lowest doses which showed significant increases of urinary protein were 2 mg Cd/kg and 4 mg Hg/kg. At dosage levels at which the kidney was injured, the metal concentrations in the kidney supernatant fractions no longer increased with dose, and those in the kidney homogenates showed a plateau. Renal critical concentrations were estimated as 11 μg Cd/g-tissue (about 100 nmol Cd/g-tissue) and 26-29 μg Hg/g-tissue (about 130-145 nmol Hg/g-tissue). The results may suggest that Cd is a potent nephrotoxin comparable to Hg in acute exposure.

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The effective removal of CHG (Chlorhexidine digluconate) from CHG-containing wastewater was investigated by use of a tublar wastewater treatment contactor with a honeycomb tube made of PVC (Poly vinyl chloride) as a supporter of biofilm. To the contactor, 30 ppm of activated sludge acclimated to the wastewater at the concentration of 0.5 ppm CHG was added and the wastewater containing about 20 ppm CHG was fed continuosly at the hydraulic retention time of 12 or 24 h. The removal rate of CHG in this experiment was 23% at the 1st day and 40-50% after the 4th day at the 12 h-hydraulic retention time and was 60-80% in the following 24 h-hydraulic retention time. The effects of temperature on the removal rate of CHG were then investigated at 10°C, 15°C and 20°C under the hydraulic retention time of 12 h. The results showed that CHG was removed less as temperature descended, contrary to expectation of the physical adsorption theory. However, at 10°C under the hydraulic retention time of 24 h, the removal rate of CHG was more than that at 20°C under the hydraulic retention time of 12 h. Furthermore, 70-80% of CHG in the wastewater containing 60-70 ppm CHG was removed at 10°C under the hydraulic retention time of 24 h. As wastewater treatment time went by, biofilm on the surface of the supporter increased. Biofilm increased on the supporter was slipped easily off by giving a soft shock in order to prevent the honeycomb tube from clogging. The removal rate of CHG recovered completely in a few days after biofilm was slipped off.

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Keratin fibers, such as those of human hair, undergo chemical damage, resulting in the production of sulfonate (-SO₃^-) groups ; this process is regarded as oxidative hair damage. This damage was measured with a Fourier transform infrared spectrometer using a high pressure diamond anvil cell. This method could be used to measure chemical damage with only small samples of fiber. In this study, the relationship between the distance from the root end of hair and -SO₃^- content at the point was determined. The observed damage patterns indicated that the degree of oxidative hair damage depended on the frequency of permanent waving and the properties of hair. This technique may be applied to a forensic chemistry, including, for example, discrimination and presumption of personal hair history.

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