Ozonation has recently been utilized in the water purification process for controlling trihalomethanes, oxidation of organic compounds with undesirable organoleptic properties and color removal, particularly in Europe. Although ozone is an effective oxidant, it is necessary from the viewpoint of public health to assess the genotoxic potentials of ozonation products from various contaminants in drinking water. This review is undertaken to summarize the mutagenicity and toxicological data of concentrates of drinking water or humic solution after ozonation. The identified ozonation products are evaluated toxicologically. Formaldehyde, glyoxal and methylglyoxal which possess high genotoxic potential may be good indicators for controlling ozonation products.

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Amongst other examples of modern technology, mass spectrometry (MS) has made extraordinary progress in the last decade in terms of sensitivity, precision and the possible range of mass measurement, progress which could not be foreseen ten years ago. Starting in 1970, a method after the method of ionization was rapidly developed in tandem with dramatic improvements and innovations in MS equipment, as a result of which the range of applications of mass spectrometry has expanded exponentially, allowing MS to assume very important new roles in various fields of the life sciences, including medicine, pharmacy and environmental chemistry. One of the most outstanding developments in MS in recent years is the ability to measure non-volatile substances such as protein, nucleic acid, glycolipids, polysaccharide, and high polarity macromolecules. The most important contribution in this development come mostly from fast atom bombardment (FAB) ionization, the latest state-of-the-art ionization methods such as electrospray (ES) ionization or ionspray (IS) ionization, new range of mass spectrometric methodology, tandem mass spectrometry (MS/MS) and time of flight mass spectrometry (TOF-MS). This review centers on an outline of the mass spectrometry of non-volatile, high polarity macromolecules, concentrating on FAB, ES, IS, MS/MS and TOF-MS.

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The handling of pathogenic organisms should always be done with utmost care. If pathogens are treated without adequate understanding of their pathogenic potential, however, problems may result. Recently, the use of pathogenic microorganisms is not confined to studies on infectious diseases, because of an increase of interest for the physiological activity of the pathogenic factors such as bacterial toxins in the field other than pathogenic microbiology. The use of such physiologically active agents is expected to grow more, and biohazards due to the use of such organisms without knowledge of infectious microbiology is feared. Although the same techniques are generally used in handling of both pathogenic and nonpathogenic organisms, additional caution is called for the former. The National Institute of Health (NIH) of Japan established the "Rules for Biosafety Control of Pathogenic Organisms" in 1988 and renewed in 1992. Pathogenic microorganisms were divided into 4 biosafety levels. The present paper deals with the problems on biosafety in handling of pathogenic organisms with special interest on the rules of NIH, Japan.

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The acute and subacute oral toxicity of selenocystine was assessed in ICR male mice. In the acute study, the estimated LD₅₀ value for a single oral dose was 76.0 mg/kg (confidence limit : 64.4-89.7 mg/kg) and the minimal lethal dose was 43.2 mg/kg. In the mice administered 50 mg/kg, the liver and kidney injuries were assumed by increase in aspartate aminotransferase, alanine aminotransferase, urea nitrogen and phosphorus, and a decrease of calcium in plasma. In the subacute study, the body weight gain of animals orally administered 10, 20, 30 and 40 mg/kg/d for 30 d significantly decreased with the dosage, and all mice given 30 or 40 mg/kg/d died within the exposure period. Although renal damage was not recognized by biochemical measurements and histopathological examinations, liver damage was apparent by increase in aspartate aminotransferase and alanine aminotransferase in plasma and histopathological findings, vacuolation of centrilobular and/or peripheral hepatocytes. Gel chromatography was carried out on the cytosol from kidney and liver of mice following a single and consecutive administrations of selenocystine. In the kidney, selenium following a single dosage of 50 mg/kg was eluted around the void volume and another fraction in Sephadex G-25 gel chromatography ; most of the selenium following consecutive dosages of 20 mg/kg/d for 30 d, however, was eluted only in the void volume. In Sephadex G-150 gel chromatography of the liver, most of the selenium following a single administration was eluted in the low-molecular fraction, whereas a major peak of selenium following consecutive administrations was eluted in the high-molecular fraction. The findings thus indicate that in the acute toxicity study selenocystine caused hepatic damage and renal damage and in the subacute toxicity liver damage, depending on selenium behavior in these organs.

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N-Chloro nitrogenous compounds were formed by addition of HOCl to an aqueous solution of ammonia, various amines, imines, amides, imides, and amino acids. The chlorination reactivities of these N-chloro compounds were evaluated with monochlorodimedone (MCD) chlorination rate constants, (kinetics was defined in a previous paper), at pH 7 and at room temperature. The rate constants varied with the structure of the nitrogenous compounds and with the number of chlorine atoms (Cl⁺) combined with the nitrogen atom in the compound. The rate constants (min^-1) for chlorinated secondary amines such as dimethylamine, diethylamine and N-methylglycine (0.338-1.540) were higher than those for monochlorinated primary amines methylamine, ethylamine, and glycine (0.169-0.464). The rate constants for strong base imines like piperazine and morpholine (0.025 and 0.031, respectively) were much lower than those for weak base imines like piperidine and piperazinedione (0.924 and 0.441, respectively). The rate constants for these monochlorinated primary amines (0.123-0.464) were higher than those for dichlorinated primary amines (0.061-0.087). In ammonia chloramines, the rate constant of NH₂Cl (0.027) at 12°C was about ten times higher than that of NHCl₂ (0.0025) at 12°C.

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A method for the simultaneous determination of glycyrrhizic acid (G) and glycyrrhetinic acid (GA) in cosmetics by means of high performance liquid chromatography (HPLC) is described. Samples (cosmetics) were extracted with tetrahydrofuran or tetrahydrofuran containing 5-10% water. The extracts were passed through Bondelute NH₂ cartridge (3 ml). After washing the cartridge with tetrahydrofuran and methanol, G and GA were eluted with a mixture of 0.2 M KH₂PO₄-acetonitrile (1 : 1). G and GA were separated and determined by HPLC on an ODS column (TSKgel-ODS 80T_M, 4.6×150 mm) using a mobilephase [CH₃CN : H₂O (65 : 35)] containing 0.2% (w/v) tri-n-octylamine, 0.4% (w/v) acetic acid, 0.1% (w/v) EDTA-2Na) Recoveries of G and GA from cosmetics (lotion, milky lotion, cream, hair tonic, etc.) were more than 95%.

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A gas-liquid chromatographic (GLC) method was developed for the determination of diethylstilbestrol glucuronide (DESG), a metabolite of diethylstilbestrol, in beef. DESG was extracted from beef with 90% acetonitrile. The extract was cleaned up without hydrolysis of DESG by Sep-pak NH₂ cartridge and C₁₈ cartridge. The purified extract was evaporated to dryness and reacted with pentafluoropropionic acid anhydride (PFPA) for 50 min at 50°C. PFPA derivatives of DESG were measured by GLC, using a 2% OV-17 column and electron capture detector. Recoveries of DESG obtained from beef spiked at 0.005-0.02 μg/g (as is DES) levels were 86.8-89.2%. The detection limit of DESG was 0.001 μg/g.

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A method for the simultaneous determination of 1, 1, 1-trichloroethane (TCE) and it's stabilizer 1, 4-dioxane (DO), 1, 2-epoxybutane (EB), nitromethane (NM), nitroethane (NE) in household aerosol products by gas chromatography (GC) was developed. In this dryspace method, an aerosol product sample was propelled into 50 ml beaker. The propelled solution (3-4 ml) was weighed in a 10 ml test tube, and the same weight of 1, 2-dichloropropane (DCP) as an internal standard was added. Sixteen μl of this sample solution was loaded to a pre-cooled syringe (25 μl), and was injected to a sealed vial (125 ml). The vial was tapped slightly for the wide spreading of the solution, and the solution was ascertained to evaporate to dryness within 3 minutes. A part of 250 μl of the vial gas was applied to GC. A fused silica capillary column was used as the GC column. If 16 μl of the sample solution had not been evaporated within 3 minutes in a vial, the headspace method was employed for the determination of TCE and the stabilizer. By this method, 20 commercial water proofing aerosol products were analyzed, and TCE was detected in 17 products in the range of 48.9-93.1%, DO was in 12 products, 1.42-2.17%, EB was in 14 products, 200-3100 ppm, NM was in 12 products, 500-2800 ppm, NE was in 3 products, 900-1000 ppm. Headspace method was employed for 2 products in 20.

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High-performance liquid chromatographic determination of O⁶-methylguanine (MeGua) was studied using phenacyl bromide as a precolumn derivatization reagent. After the selective condensation of O⁶-MeGua to form fluorescent 9-methoxy-6-phenylimidazo [2, 1-b] purine (phenyletheno-O⁶-MeGua), separation of that compound from guanine and 7-methylguanine was achieved on an ODS column (150 mm×4 mm i. d.) with acetonitrile-50 mM ammonium dihydrogenphosphate solution containing 5 mM Na 1-octanesulfonate (25 : 75), and the separated etheno-O⁶-MeGua derivatives was detected with a fluorescence monitor (319 nm for excitation and 404 nm for emission). O⁶-MeGua can be detected as phenyletheno-O⁶-MeGua by a fluorometric detector at a level of 40 pg (signal/noise=2). 2'-Deoxyguanosine (dGuo) was reacted with various methylating agents to furnish O⁶-methyldeoxyguanosine (MedGuo). Then, O⁶-MeGua, which is given from O⁶-MedGuo by acid hydrolysis, was determined by the fluorometric derivatization.

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Commercial Food Yellow No.5 showed genotoxic activity in Drosophila wing spot test. Seventy-two hours larvae of Drosophila were treated chronically (during the whole third larval instar) with commercial Food Yellow No.5. The frequencies of single spots increased 4-fold that of control. Commercial Food Yellow No.5 involved some impurities. Impurity fraction A, which contained more polar compounds than Food Yellow No.5, showed DNA damage in Drosophila DNA-repair test. These results suggested that the impurities would be contributed to the genotoxicity of commercial Food Yellow No.5.

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A sensitive qualitative color test for residual hydrogen peroxide (H₂O₂) in foods treated with H₂O₂ was investigated. Color tests using peroxidase and 11 kinds of chromogenic reagent and peroxide test strip were compared and evaluated for coloration of color reagents blank and detection sensitivity of H₂O₂ in the standard solution and in 3 kinds of food. The color test using N-ethyl-N-(2-hydroxy-3-sulfopropyl)-m-toluidine (TOOS)-4-aminoantipyrin (4AA) was most suitable for the qualitative test. A qualitative color test using TOOS-4AA is as follows : 5 ml of a color reagent containing peroxidase, TOOS-4AA and potassium bromate was added to 5 g of the minced sample, and this mixture I was stood for 5 min with occasional shaking. On the other hand, 0.5 ml of the catalase solution and 3.5 ml of the chromogenic solution containing TOOS-4AA were added to 5 g of the same minced sample, and this mixture II is stood for 5 min with occasional shaking. After standing, 0.5 ml of the peroxidase solution and 0.5 ml of the potassium bromate solution were added to the mixture II, and shaken for 10 s. The mixtures I and II were filtered through absorbent cotton. The presence of H₂O₂ in the sample was judged from the difference between colorations in the both filtrates. Hydrogen peroxide in 13 kinds of food was all negative by the qualitative color test using TOOS-4AA, and detection sensitivity for added H₂O₂ in those foods was 0.1 or 0.2 μg/g. These results suggested that the qualitative color test using TOOS-4AA could detect a trace amount of residual H₂O₂ in 13 kinds of food.

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Determination of metallothionein (MT) by the Cd-Chelex method was investigated using dry Chelex, and the Cd-Chelex and Cd-hem methods were compared for the estimation of MT from the brain, heart, lung, liver, kidney, spleen, and testis of rats injected with CdCl₂. There was in relatively good agreement between these two methods on the determination of the tissues MT containing Zn and Cd.

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The indications on packages of paper bags for electric vacuum cleaners had antimicrobial agents changed. Benzimidazole and biguanide compounds were newly indicated as antimicrobial agents, and pyrethroid compounds were as insecticides. Thiabendazole and methyl benzimidazolylcarbamate were identified as benzimidazole compounds. In 3 or 2 out of 7 paper bags, these two compounds were determined in the ranges of concentration of 3-513 μg/g and 1-160 μg/g by high performance liquid chromatography (HPLC), respectively. In 1 out of 7 paper bags, as a biguanide compound, chlorhexidine was identified and determined in the concentration of 1300 μg/g by HPLC. On the other hand, in 5 out of 7 paper bags, as a pyrethroid compound, permethrin was identified and determined in the concentration of 82-6310 μg/g by gas chromatography. In most of the paper bags analyzed, larger amounts of these 4 compounds were present in the inner bags than in the outer bags.

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Thirty elements in thirty-seven foods (forty-three samples as a whole) that are commercially called health food were determined simultaneously by inductively coupled plasma atomic emission spectrometry (ICP-AES). All samples were digested with nitric acid using a Teflon vessel digestion bomb. The analytical data for reference standard materials by this method show good agreement with the certificate values for the materials. The ICP-AES is very powerful for the determination of multielements in the food. It takes only 3 minutes for the determination of 30 elements in a sample solution. Arsenic, boron, cadmium and potassium concentrations were higher in the food containing Tangle than those in the others. Further, aluminium, copper and zinc concentrations in the foods containing Oyster tissue and barium, magnesium and manganese in the foods containing Kidachiaroe (Aloe arborescens MILL.) were remarkably higher than those in the other foods. On the foods containing vegetable oil or animal oil or animal oil, the levels of the determined elements were significantly low. In the several foods, the additives have a strong influence on the concentrations of some elements : sodium ferrous citrate and powdered Bovine bone for the foods containing Kidachiaroe and Mannentake (Ganoderma lucidum) respectively have significant effects on the concentrations of iron and sodium in the former and chromium and lead in the latter, respectively. It seems important to check the safety of the health foods, because several toxic elements such as cadmium, lead and chromium were detected in a few foods.

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