Waste treatment is one of the important problems concerning the environmental protection. In this paper, some problems are surveyed from the viewpoint of hygienic chemistry. In the process of waste treatment, burning and/or dumping, harmful and toxic substances are generated. Among the studies of the behavior of the pollutants, offensive odor, methyl mercury, mutagenic substances and dioxine are progressing. Odor pollutants generated from model garbage and a waste disposal factory were identified by gas chromatography or gas chromatograph-mass spectrometric data system. The field survey for a disposal site was performed, and concentrations of gases from gas wells were measured. Methylation of mercury by humic substances and by ash from refuse incineration was observed. Humic substances are still contained in ash, because some refuses are in-completely burnt. Organopolysiloxianes found in ash from incinerator methylated inorganic mercury. Mutagenic activity of refuse leachate, emission gas from municipal incinerator were determined. Polyaromatic hydrocarbons and nitropyrens as mutagens were found. The relative contributions of various routes of emission from the incinerator in the output of mutagens were evaluated. Continuous operation with a complete combustion system and activated sludge process is effective to prevent the emission of mutagens. Dioxines generated from refuse incinerator were measured in each stage of the incineration plant. Bag-filter is effective to remove its emission into atmosphere.

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Efficient and simple extraction method for cocaine in human urine was developed by the addition of tri-n-propylamine to the urine sample and by the use of GC/MS for the determination. The quantitative extraction of trace amounts of cocaine in the human urine is very hard with conventional organic solvents. However, in the present study, tri-n-propylamine was found to extremely raise the extractability of trace amounts of cocaine. The recommended procedure is as follows : to 20 ml urine containing less than 1.2 μg of cocaine in 50 ml separatory funnel, 1 ml of 15% sodium carbonate aqueous solution, 1 ml of aqueous solution saturated with tri-n-propylamine, and 10 ml of dichloromethane are added. It is shaken for 3 min and centrifuged for further 3 min at 3500 rpm in a 50 ml centrifuge tube. To a part (5 ml) of the resulting dichloromethane phase, 1 ml of n-tricosane dichloromethane solution (537 ng/ml) is added as an internal standard. The solution is then concentrated on a water bath to 0.2 ml at 60±5°C and the cocaine is determined by GC/MS. The extraction efficiency was 97% at least of 20 ng of cocaine·HCl tested. In human urine containing less than 1.2 μg of cocaine, the extraction efficiency was always higher in the presence of tri-n-propylamine than in the absence of the base.

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Within recent years, concern over contamination with organic compounds in aquatic environment has risen. But due to the extremely low levels and many kinds of organics present, it is difficult to get sufficient information about all compounds. Therefore mutagenicity is studied on tap water, river water and river sediment. This report is on mutagenicity of dichloromethane (DCM) extracts from the sediments which were collected at 7 points in the Nakatsu river during 1987. The Nakatsu river is a branch of the Sagami river used for drinking water supply in Kanagawa prefecture and has the best quality of water among branches. However, it is obvious that those sediments show mutagenicity (2-20 times as many as spontaneous revertants per 5 g dry weight) by using the strain TA98 of Salmonella typhimurium with S9mix. Certain sediment also shows mutagenicity without S9mix. DCM extract of some sediments are separated to acidic, neutral and basic portions, and the neutral portion is fractionated to three fractions on a silicagel column (Fr. 1, Fr. 2 and Fr. 3). Futhermore Fr. 3 is fractionated to three sub-fractions with HPLC (sub-fr. 1, sub-fr. 2 and sub-fr. 3). Each fraction is surveyed with both the Ames test and GC-MS analysis. As the result it is confirmed that Fr. 2 gives 10-26% of the total mutagenicity observed in the sediment and contains many kinds of mutagenic polynuclear aromatic hydrocarbons. It is also found that Fr. 3 gives the residual mutagenicity which mainly depends on sub-fr. 2. But the mutagenicity in Fr. 3 is not able to be explained because of the existence of unidentified peaks on GC-MS. We are investigating these unknown compounds which cause the mutagenicity of the Nakatsu river sediments.

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A newly developed slice method is proposed for judging whether or not phosphates are employed in fresh vegetables. This method involves 1) the determination of the concentration distribution of eluted phosphates from the surface to the inside of the sample, 2) the comparison of the outer concentration of phosphates with the inner one to decide whether phosphates were used in the sample. It is characteristic of this method that no consideration is needed for individual difference among the samples. With the samples such as bean sprout and flakes of edible burdock root, to which the slice method could not be applied because of their small volume, it was found that the amounts of naturally occurring phosphates to be eluted from the samples increased with decreasing their freshness. Consequently, with the samples colored slightly brownish or brownish, indicative of the appreciable elapse of time after their preparation, it should be extremely careful to decide whether the samples are treated with phosphates, by comparing the amounts of phosphates eluted with their background values.

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Round robin study was carried out to investigate the precision of the determinations of trihalomethanes in water by the solvent-extraction gas chromatographic (GC) method and the head-space GC method which are prescribed by the Japanese Ministry of Health and Welfare. Four samples of water with chloroform, bromodichloromethane, dibromochloromethane and bromoform were analyzed by 14 different laboratories : 13 laboratories measured the concentrations of the four compounds by the solvent-extraction GC method and 12 laboratories, by the head-space GC method. The results show that the intralaboratory precision was better than the interlaboratory precision by analysis of variance ; the precision of the results by the solvent-extraction GC method was better than those by the head-space GC method in many cases. The mean obtained by the head-space GC method was significantly larger than that obtained by the solventextraction GC method in some cases.

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Gas chromatographic and mass spectrometric method was applied to the determination and identification of aloe components, barbaloin (BA) and aloenin (AL), in skin care cosmetics. After removal of volatile substances in vacuo, the sample was dissolved in water and treated with Sep-Pak C₁₈ cartridge. The eluate with methanol was evaporated to dryness in vacuo, and a trimethylsilylation was achieved with bis (trimethylsilyl) acetamide and acetonitrile at 70°C for 60 min. The reaction mixture was injected into a gas chromatograph and a gas chromatograph mass spectrometer with a megabore DB-1 capillary column. The recoveries of BA and AL added to the lotion and cream samples were more than 85% in the lotion and more than 67% in the cream, and with the identification limit of 2 μg/g and 4 μg/g, respectively. BA and AL in commercial cosmetics, cosmetic raw materials and aloe leaves were successfully determined and identified.

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The analytical methods were developed for the simple and rapid determination of triacetin in gummy candy by TLC, IR, and GC. The extraction method from gummy candy is as follows. The gummy candy was dissolved in warm water. The water solution was extracted with chloroform after cooling. The chloroform layer was washed with 10% NaHCO₃ to remove dehydroacetic acid (one of interferences). Then the interferences of natural oil soluble pigments, preservatives, and others were successfully removed by use of a silica gel column. The eluted triacetin fraction could be analyzed qualitatively by use of TLC with silica gel plate and IR with KBr disk. Moreover, this fraction did not contain interferences on the quantitative analysis by GC. The analytical recovery of triacetin from gummy candy by this GC method was 99.4%. The detection limit was 10 ppm. Triacetin was detected from two samples out of 20 gummy candies on the market.

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The kinds and amounts of silver salts used in the acidic COD-Mn determination were investigated. Ag₂SO₄ should be weighed every using time and mixed well for a long time with magnetic stirrer. If the mixing was imperfect, masking of chloride ion was insufficient and catalytic effect by Ag ion was weakend. On the other hand, AgNO₃ perfectly inhibited the consumption of KMnO₄ by Cl^- and was easy to be handled. The catalytic effect of AgNO₃ (20%, 5 ml in standard method) was sufficient unless the Cl^- concentration in a sample solution was not very high. If the sample solution contains large amount of Cl^- above 500 mg/l, the equivalent amount of AgNO₃ to the chloride ion should be further added. But the development of catalytic effect would be low when coexisting Cl^- was very high. On the determination of acidic COD values of environmental water samples, good agreement was obtained when Ag₂SO₄ or AgNO₃ was used carefully and so AgNO₃ can be used in any samples unless they contain specific contents predominantry.

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Mutagenicity and benzo [a] pyrene content in extracts from smoke of mosquito coils and nonsmoke mosquito mats were investigated in the Salmonella/S9 mutagenicity test. Extracts from smoke of mosquito coils showed mutagenic response with or without S9mix to TA100, and with S9mix to TA98. Mutagenic activity (TA100, +S9mix) of extracts from mosquito coils smoke was approximately 1/3-7/10 times that of cigarette smoke. Volatile matters generated from nonsmoke mosquito mats were slightly mutagenic to TA100 in the presence of S9mix.

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