There are various drugs to be analysed in the forensic science. Of all analytical methods, an immunoassay is suitable to detect some drugs in biological materials because of its high sensitivity and simple pretreatment. This review has been presented on the method for the preparation of immunogen, principles of non-isotopic immunoassays, and immunoassays as the screening method with microtiter plate and/or latex particles. The examples of hapten synthesis were the drug causing dependence and pesticides. The immunoassay will be a more powerful tool in using monoclonal antibody and developing a simple and rapid analytical system.

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The causes of the appreciable increase of dimethyl disulfide (DMDS)-forming bacteria in abnormally conditioned activated sludge were investigated. The strains II-Ab-43 (Corynebacterium) and III-Ab-5 (Pseudomonas), which were isolated from abnormally conditioned activated sludge under high biochemical oxygen demand (BOD) loading, were used to find suitable environmental conditions for DMDS formation and for growth. Both strains formed DMDS at high concentrations and grew well in culture medium with weak alkalinity and a high content of BOD substances, at 20-30°C. Activated sludge was cultured at the BOD load of 0.55 kg-BOD/m³·d at various pHs from 6.0 to 9.5. The state of activated sludge was normal at pH 6.0-8.5, but abnormal at pH 9.5. The DMDS-forming ability of the mixed liquor was constant at low values at pH 6.0-8.5, but increased distinctly at pH 9.5. With an increase of BOD load to 5.5 kg-BOD/m³·d at pH 9.5, the state of activated sludge deteriorated and the DMDS-forming ability rose further. In the aeration tanks of night soil treatment plants, DMDS was detected under conditions of weak alkalinity (pH 8.4-9.1) and high BOD of the influent (BOD 501-5540 mg/l). These results agreed with those obtained in the laboratory. The effluent parameters (BOD, chemical oxygen demand (COD), suspended solids (SS)) from settling tanks in which DMDS was detected in the aeration tanks had higher values than those in cases where DMDS was not detected. It became clear that environmental conditions of weak alkalinity and high BOD, due to abnormally conditioned activated sludge, were suitable for the growth of DMDS-forming bacteria, and DMDS was consequently detected in the aeration tank. It appears that DMDS could be a useful index for evaluating the state of activated sludge.

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It was reported in May, 1985 that diethylene glycol (DEG) intentionally added was found in Austrian and German wines. In order to eliminate the growing anxiety of the citizens in Hamamatsu, we investigated the contents of DEG in wine by using the analytical method of DEG specified by the Ministry of Health and Welfare of Japan with some modifications. The DEG in wine was confirmed with an authentic standard in gas chromatography (GC-FID) by using Thermon-3000, PEG-20M, and DEGS as liquid phase as well as in gas chromatography-mass spectrometry, and was finally quantified with GC-FID (PEG-20M). DEG was detected in 5 out of 80 wine samples in the range of 0.015 to 2.3 g/l. It was found that the higher the grade of wine, the higher the tendency of DEG detected. In the course of this study on DEG analysis, 71 samples of wine were found to have glycerin in average amount of 8.3 g/l (13.9-40 g/l), and like DEG, the wines of higher grade tended to have higher amount of glycerin.

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A method for quantitative determination of four harmful metals, Cd, Cu, Mn, and Pb in water by means of coprecipitation with zirconium hydroxide, Zr (OH)₄, followed by flame atomic absorption spectrometry has been developed. Because no extraction process of the metal chelates with organic solvents is required, and because Zr shows low toxicity to mammals, this procedure is free from hazard to the health of laboratory workers engaging in metal analysis. The results of recovery tests indicated that the recoveries of the metals by the above procedure are satisfactory (more than 98%).

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The differences of reactivity with N, N-diethyl-p-phenylenediamine (DPD) indicator reagent among N-chlorinated nitrogenous compounds were investigated. The DPD color development with N-chlorosuccinimide started immediately after addition, but it took several minutes to complete. Consequently, if titration with ferrous ammonium sulfate (FAS) is begun too quickly, it would reach an apparent end point (quenching the DPD color) before the coloration of DPD with N-chlorosuccinimide had reached its end-point. Subsequently, coloration would continue until all of the remaining N-chlorosuccinimide had taken part in the DPD coloration. Thus, when chlorosuccinimide solution is titrated by the normal DPD-FAS titrimetric procedure, an erroneous result would be obtained, suggesting the presence of both free and combined residual chlorine. Similar time courses of DPD color development were observed with mixtures of hypochlorite and imides and other nitrogenous compounds. When water containing succinimide, phthalimide, or other such compounds is chlorinated, and residual chlorine is measured by the normal DPD-FAS titrimetric procedure, erroneously high values for free available chlorine and low values for combined chlorine would be obtained, and the values obtained would be dependent on the time taken to perform the titration. A catalytic amount of KI is used in the DPD-FAS titrimetric method for differentiation of residual chlorine. The relation between the rate of DPD color development with some N-chloro compounds and the amount of KI added to the mixture was studied. The rate of color development in the presence of KI and the amount of KI needed to evoke a rapid coloration differed from N-chloro compound to N-chloro compound.

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A simple and rapid method by high performance thin layer chromatography (HPTLC) was studied for the determination of dithiodiglycolic acid (DTDGA) in hair-waving solutions. Sample and standard solutions were spotted on a silica gel plate. Immediately the plate was developed with diisopropylether-formic acid-water (90 : 7 : 3 v/v) for the separation of DTDGA and thioglycolic acid (TGA). The plate was sprayed with detecting solution : dissolve CuSO₄·5H₂O in a little distilled water, made up with methanol. DTDGA and TGA was visualized by heating for 30 min at 100°C. Densitometric determination was carried out with TLC scanner. DTDGA in the range of 0.5-20.0 μg was determined by the proposed method with spotting 1 μl of samples. And the HPTLC procedure in this paper was applicable to the quantitative analysis of DTDGA without an influence of other ingredients in hair-waving solutions.

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In order to clarify the origin of mutagenic impurities in the commercial cosmetic Lithol Rubine B (C.I. 15850) and Lithol Rubine BCA (C.I. 15850 : 1), several dye samples were synthesized under various conditions and their ethyl acetate extracts were tested for mutagenic activities in the Ames test. When the amount of diazotized 2-amino-5-methylbenzenesulfonic acid in the diazo solution was more than that of 3-hydroxy-2-naphthalenecarboxylic acid in the coupling solution in terms of the theoretical amount, mutagenic compounds were produced as reaction intermediates or by-products without exception. However, mutagenic compounds were never produced when the amount of the former was less than that of the latter in terms of the theoretical amount. The reaction temperature did not affect the production of mutagenic compounds. The mutagenic compounds in the synthetic Lithol Rubine BCA could be removed from the calcium lake by rinsing with water.

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Number of accidental death and suicide cases involving the use of alkyldipyridylium herbicide (paraquat and diquat) have been increasing all over the world. As a separate and identification methods, its insoluble salts were prepared by the reaction of the herbicide with hydrogen hexachloro platinate (IV), hydrogen tetrachloroaurate (III), reinecke salt and picric acid. Their formation system, yielding rate, melting point (decomposition point) and elemental analysis were checked to identify those salts by infrared absorption spectrum.

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