The direct effect of cadmium on bone metabolism and interaction between cadmium and zinc or copper in tissue culture are described in this review. One ppm cadmium stimulated ⁴⁵Ca release from ⁴⁵Ca-prelabeled bone from 9-d-old chick embryo, but 30 ppm cadmium inhibited ⁴⁵Ca release. Mineralization and collagen synthesis were inhibited by cadmium of 1 ppm and above. Since Cdtreated bones in the culture system showed a decrease in both mineral and collagen, the change in the cultured bone is not osteomalatic but osteopororic and agrees with the bone change of cadmiumtreated animal rather than with that of Itai-itai diseased patient. The difference in bone lesion between humans and cadmium-treated animals suggests that factors other than cadmium participate in the etiology of Itai-itai disease. We gave attention to zinc, copper and lead as factors other than cadmium, which were found in the bones of Itai-itai diseased patients and in cadmium-polluted rice. A cadmium-induced decrease in collagen content was protected by zinc but enhanced by copper. A cadmium-induced decrease in mineral content was unaffected by zinc and copper. These results point out that copper aggravates cadmium-induced osteoporotic change and cadmium plus zinc-treated bone shows a decrease in mineral without a decrease in bone matrix to give an osteomalacia-like change. Therefore, it is suggested that a ratio as well as each dose of three metals influences whether bone damage in vivo is osteoporotic or osteomalatic.

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A colorimetric determination of diphenylether herbicides ; CNP, NIP and X-52 (chlomethoxynil), was achieved according to the procedure for the colorimetric determination of organophosphorus pesticides ; EPN, parathion and methylparathion, which consists of n-hexane extraction, reduction with zinc, diazotization with nitrite and then coupling reaction with N-(1-naphthyl) ethylenediamine. Diazo-coupling derivatives of CNP and NIP have λ_max at 570 nm and mol absorptivity (ε) is 3.2×10⁴ (CNP) and 3.3×10⁴ (NIP), but X-52 does not yield sufficient intensity (ε : 0.1×10⁴ at 585 nm) for the presented method. The sample water alkalized with NaOH is extracted with n-hexane and the extract is shaked with HCl (1 : 9). After layeres separate, aqueous layer contained CNP-amino and NIP-amino is treated to form their diazo-coupling derivatives directly and n-hexane layer contained CNP, NIP, X-52 and fenitrothion is subjected to florisil column chromatography. The 2% ethylether/n-hexane 50 ml eluate for CNP, the next 70 ml eluate for NIP and the 5% ethylether/n-hexane 100 ml eluate for X-52 are reduced and reacted to form their diazo-coupling derivatives. The average recoveries at the 0.2 and 2.0 ppm level throughout the procedure were 79% (CNP), 80% (NIP), 0% (X-52) and 95% (CNP-amino+NIP-amino).

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Commercial samples and pure chemical samples of Sudan III (C. I. 26100) and Scarlet Red (C. I. 26105) were tested for mutagenic activities in the Ames test. Three out of five commercial samples of Sudan III were mutagenic to Salmonella typhimurium TA98 and TA100 in the presence of S9 mix, and all of the commercial samples of Scarlet Red tested were mutagenic to the two strains with microsomal activation. Neither of the purified dyes, however, was mutagenic to these strains with or without S9 mix. These results demonstrate that contaminants present in these commercial diazodyes were responsible for the mutagenic activity. Some of the contaminants were separated by preparative thin layer chromatography, and the starting materials of the azo-dyes, i. e. p-aminoazobenzene (AB) and o-aminoazotoluene (oAT), were found to be the main mutagenic contaminants.

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A head space method was studied for the quantitative determination of toluene in tissues by gas chromatography (GC). The method may be summarized as follows. Tissue was minced by extruding it from a plastic syringe into an equilibration vial containing water, sodium hydroxide, olive oil and an internal standard (ethylbenzene). As a standard sample, another equilibration vial having the same components plus authentic toluene but without tissue was used. Both vials were rapidly sealed with Teflon-rubber packing, and then shaken at 35°C for 2.5 h in a water bath. One milliliter of warmed head space gas was subjected to GC. The concentration of toluene in tissue was calculated by comparing T/I (T, peak height of toluene ; I, peak height of internal standard) of the tissue sample with that of the standard sample. This method was found to be useful for determining toluene in the range of 0.002 to 10 mg/g in tissue.

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It was investigated whether or not the umu test, a new screening method for mutagens by use of Salmonella typhimurium TA1535/pSK1002, was applicable to organic extracts from airborne particulates. First, when nutritious medium was generally used in the test, the mutagenic activities were found to be rather weak in the case of both the extracts with S9 mix and 2-nitrofluorene without S9 mix. However, these values turned out to increase by a revised method by using a simple medium restricted nutritionally ; this method had a similar sensitivity to Ames test for the extracts and 2-nitrofluorene ; there arose adequate dose-response relationships between amounts of the extracts and their mutagenic activities in the presence and absence of S9 mix. It was therefore suggested that this revised method could be applied to the extracts to assay these mutagenicity due to its improved sensitivity in addition to easiness and quickness.

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A model experiment was performed to study the behavior of pesticides in foods during cooking treatments, by means of introducing a sample piece of filter paper in stead of food, and it was carried out with 14 pesticides. Most of pesticides used showed little decrease in remainings by washing with or without detergent and the difference between the washing treatments was not distinguishable. Heating in water (boiling) and in oil (frying) reduced the pesticide remainings in the sample due to decomposition and migration into the solvents. During soaking, a certain amount of pesticide was released into the solvents. Residual amounts of pesticides after heating in air (baking) varied from one to another. Behavior of pesticides during cooking treatments was found to be associated with physicochemical properties of individual pesticides, such as molecular weight, boiling point and solubility in water or oil.

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To examine the reaction process for trichloromethane formation through the chlorination of acetone in the neibourfood of pH=7, acetone was allowed to react with chlorine aqueous solution at 25°C, pH=1-8. The results obtained were as follows : (1) Monochloroacetone was formed at pH=1-5, but 1, 1-dichloroacetone, 1, 1, 1-trichloroacetone and trichloromethane were not detected. (2) At pH=6-7, monochloroacetone, 1, 1, 1-trichloroacetone and trichloromethane were found. (3) At pH=7.8, monochloroacetone and trichloromethane were formed, but 1, 1, 1-trichloroacetone was not detected. Therefore, it was concluded that the formation of monochloroacetone is a rate-limiting step in the reaction sequence at pH=7 and the amounts of trichloromethane depend on the concentration of OH^- in the following equation. CH₈COCCl₃+OH^-→CH₃COO^-+CHCl₃

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A simple gas chromatographic method has been developed to determine 2, 4-and 2, 6-diaminotoluenes in commercial polyurethane foams. 2, 4-and 2, 6-Diaminotoluene could be detected as heptafluorobutyryl derivatives by using an electron capture detector ; the lower limits of detection were 5 pg and 2 pg, respectively. It was found that 2.7-3.0 μg/g of 2, 4-and 1.3-1.9 μg/g of 2, 6-diaminotoluene were present in three commercial polyurethane foams. Mutagenicity test for 2, 4-, 2, 6-diaminotoluenes and toluene extracts of polyurethane foams was performed by the Ames method in Salmonella typhimurium TA 98 and TA 100. The toluene extract of polyurethane foam containing 3.08 μg of 2, 4-and 1.90 μg of 2, 6-diaminotoluene, was mutagenic in TA 98 (143 revertants/g polyurethane foam), whereas mutagenicity of pure 2, 4-and 2, 6-diaminotoluene was 1410 and 370 revertants per 100 μg, respectively.

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Carps were kept in water containing 0.1, 0.05 and 0.01 ppm of Pb, 0.05 ppm of Cd, or 15 and 1.5 ppm of Cr (VI) for 5 or 6 months, and the metal contents in the organs and tissues were determined. The carps in all groups exposed to the metals, except for 15 ppm Cr-group, appeared similarly to the control fish throughout the experiments. In Pb-groups, the Pb content of gills was much higher than those of kidney, viscera (hepatopancreas, digestive tract and gall-bladder), eye, muscle and skin, and the accumulation was kept even after 6 month. In fish exposed to 0.05 ppm-Cd, the metal was concentrated extremely and specifically in the kidney to give the concentration coefficient about 1600 after 5 month-exposure. The Cr was detected in various organs including kidney, hepatopancreas and gills, and the accumulation stopped within 3 months in 1.5 ppm Cr-group.

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Systematic investigation of the COD_Mn of aldehydes and alcohols was carried out by using semimicro method previously reported. Formaldehyde was oxidized rapidly up to 74% in acidic method, but the other aldehydes decomposed gradually. The mechanism was investigated with GC method and it was clarified that aldehydes were converted to the corresponding fatty acids which were further oxidized to shorter carbon chain fatty acids. AgNO₃ added to the solution promotes these reactions as catalysis. In alkaline method, aldehyde consumed oxygen rapidly and produced the corresponding fatty acid and shorter carbon chain fatty acids simultaneously. Alcohols consumed oxygen gradually in acidic method and catalytic effect of AgNO₃ was recognized in the case. It seems that this effect occurs not only for fatty acids produced from alcohols but also for alcohols themselves. COD values decreased in secondary alcohols, and rather increased in tertiary alcohol with acidic method but diminished remarkably with alkaline method. These mechanisms of oxygen consumption will be very important when COD values of test samples containing aldehydes and alcohols are estimated.

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In mice pre-induced MT by the Zn injection (10 mg/kg, s. c.), the mortality of the mice injected with the lethal dose of Cd (10 mg/kg, s. c.) decreased more significantly (p<0.01) than that of the control group. But, this protective effect of the preinjection of Zn was not observed in the case of increasing dose of Cd to 15 or 20 mg/kg. However, induced high concentration of MT by the pre-injection of Zn (50 mg/kg, s. c.), the mortality of mice, which were injected s. c. with Cd at the dose of 20 or 30 mg/kg, decreased more significantly than that of the control group (p<0.05 or 0.01). These results indicate that high concentration of MT is significant to prevent acute Cd toxicity.

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The identification and determination of cabohydrates in low molecular fraction and determination of molecular weight of carrageenans in high molecular fraction of 5 carrageenans of food additives separated by Sephacryl S-300 column chromatography were studied. Lactose, glucose or sucrose was identified by thin-layer chromatography (TLC) as low molecular weight carbohydrates in carrageenan of food additives. By the phenol-sulfuric acid method by use of saccharide identified by TLC as a standard, the contents of mono-and disaccharides in carrageenans of food additives obtained from low molecular fraction separated by Sephacryl gel filtration, outer solution dialysed with cellophane tube and extraction with 80% methanol were found to be within the range of 20-60%. The molecular weight was more than 100000 for each of carrageenans in carrageenans of food additives by Sephacryl S-300 chromatography with well-characterized dextrans. Sulfate contents of carrageenans by the barium sulfate gravimetric method were found to be above 18%, except one to be 7.5%.

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A thin-layer chromatographic method with flame-ionization detector for the quantitative evaluation of methomyl (S-methyl N-[(methylcarbamoyl) oxy] thioacetimidate) in serum and urine is described. Methomyl in biological fluids was separated and purified simply and rapidly by passing the samples through a Sep Pak C₁₈ or Silica cartridge, in contrast to the complicated pretreatment required in conventional methods. The detection limit was 0.07 μg in the spotted volume using Chromarod A with acetone-hexane (1 : 4, v/v) as the solvent system. The recoveries were 104.0% in serum, and 98.5% in urine. Further, the method showed good precision ; the coefficient of variation was 2.4% in serum, and 4.0% in urine. The reproducibility was satisfactory, and this method could be performed far more simply and rapidly than the conventional ones.

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