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The determination of odor recognition threshold values of n- and iso-amyl (pentyl) acetates was carried out by odor panel test (Japanese students 18-22 years old;6 males and a female) using 10-liter Tedlar bag static method. The trace concentrations of n- and iso-amyl acetates in the Tedlar bag were determined by gas chromatography and an odor sensor (SnO 2 type). The odor recognition threshold values of amyl acetates were 7.70 ppm for n-amyl and 1.50 ppm for iso-amyl. The odor quality from several odor panels were evaluated, such as a binder solvent-like, aqueous paint, stimuli, fruity, aromatic, ether-like, gasoline-like, pungent, minty, sour, petroleum-like, respectively.

Analyses of environmental and biological specimens were carried out by PIXE. The yield of potassium (Kα line) is used as a standard for other elements. Environmental and biological samples studied here are standard polished glass beads (30/60 mesh), soil dust generated by studded tires. materials accumulated in a water supplying pipe, perfumes of China and Japan, ash. asbestos-dark, briquettes, synovial fluids, sex skin of a chimpanzee and so on. Concentrations of K, Ca, Fe and Zn in these biological samples are noticeable.

Elemental composition in synovial fluids from six patients with various arthritides was investigated to clarify the difference among the clinical cases using PIXE analysis and ion chromatography. Cl, K, Ca, Mn, Fe, Ni, Cu, Zn and Br were detected in the PIXE spectra and Cl−, K+, Na+ and uric acid ions were determined by ion chromatography. These results were discussed in relation to the diagnostic findings.

Two critical-point dry pellet samples of a human foot articulation hypodermic tumoral carcinosis by direct paracentesis and mass extirpation were investigated by particle-induced X-ray emission spectrometry (PIXE) and X-ray powder diffractometry. The data show that the Cu-high concentration due to rheumatoid arthritis, uric acid(-Na) monohydrate, CaHPO4·2H2O, (NH4)2FeP2O7·2H2O are represented as major uric acid (-Na) and minor pyrophosphate in the samples

The capillary gas chromatography of the C2-C5 lower aliphatic aldehydes (e.g.,acetaldehyde, propionaldehyde, n- and i-butyraldehydes, n- and i-valeraldehydes) which, in the free form in air, have unpleasant odors and low threshold odor values, has been studied using cold-trap preconcentration with liquid oxygen. The capillary column outlet was connected to enable simultaneous detection by FID, ECD, FPD AND FTD (SID).

大気中極微量低級脂肪酸(C2～C5)捕集用アルカリビーズ{1%水酸化ストロンチウム/ガラスビーズ15/28メッシュ}(市販品)を脱イオン水及び0.3M塩酸などで抽出後イオンクロマトグラフ測定した結果,アルカリ分の水酸化ストロンチウム含量は最大0.3%(w/w)であった.ビーズ表面前吸着成分は,窒素キャリヤーガス(50ml/min)下280℃高温加熱と200℃5%ギ酸水溶液約1μl3回導入で極限まで低減できた.常量使用{500mg,Sr(OH)2として24.66×10-6当量}ビーズ吸着低級脂肪酸約0.12×10-6当量の破過容量は,200℃で窒素約2l,室温で約60lであった.ビーズ捕そく低級脂肪酸再生は,窒素ガス下200℃-5%ギ酸溶液1μl(0.5×l0-6当量)1回導入で定量的であった.本法は,ビーズ表面での低級脂肪酸反応吸着後,気相-酸アルカリ熱反応系による吸着低級脂肪酸再生に基づく二段階の選択性を特徴とする.約10回の繰り返し使用で定量性が失われたが,これはビーズ表面が炭酸塩やギ酸塩に変化し劣化するためと考えられた.

The odorants discharged from several odor sources, i.e., a hospital sick(intensive care unit, ICU)room air, a hospital food, end tidal expired air and others were classified into eight compounds group I, sulfur compounds; group II, lower aliphatic amines; group III, carbonyl compounds; group IV, hydrocarbons; group V, lower aliphatic mono alcohols; group VI, phenols; group VII, lower fatty acids; group VIII, indoles) and were analyzed by a systematic gas chromatography. The graphical representation of these data is effective for rapid recognition of the whole state.A polar co-ordinate pattern display was also proposed for the explanation of the relationship between odor characteristics(odor quality and intensity) and chemical analysis data of the odor charts responsible for each odor discharged from several odor sources.

Determination of trace amounts of acetone at (sub-ppm level) in air by atmospheric pressure ionization mass spectrometry (API-MS) was studied. Air samples were directly introduced to the ion source of the instrument without pre-concentration. This technique (positive mode) is also used for real-time analysis of air samples with rapid scanning, and has been shown to be highly sensitive for acetone (at sub-ppm levels). The peaks at m/z 19, 37, 55, 73, 91, corresponded to protonated water clusters of (H2O)H+, (H2O)2H+, (H2O)3H+, (H2O)4H+, and (H2O)5H+, respectively. The peak at m/z 47 was due to (C2H5OH)H+, and that at 59 due to ((CH3)2CO)H+ (acetone). They showed good repeatability with a relative standard deviation of less than about 5%. The API-MS voltage response produced a straight line in the approximate range 0.01 to 0.1 ppm of acetone in air.

The purpose of this paper is to compare the published odor threshold values of six odorants. In Japan, all of the odor threshold values used in the Offensive Odor Control Law (enacted in 1972) were determined in an odor-free room (4 m3) by a trained panel (20 men, ages 30–45 years who were perfumers) who sniffed the odors directly and made absolute judgments of odor quality and intensity. In The Netherlands, sensorial odor concentration measurements were made with an olfactometer in a mobile sniffing car with eight panelists, four men and four women, ages 18–40 years. Such presentations are repeated with different dilution ratios. Comparison of the threshold data for the six different compounds given as the barely perceptible concentration level revealed striking similarities for hydrogen sulfide (in Japan 0.0005 ppm/in The Netherlands 0.0003 ppm), phenol (0.012/0.010), styrene (0.033/ 0.016), toluene (0.92/0.99), and tetrachloroethylene (1.8/1.2) but not for m-xylene (0.012/ 0.12). Such a similarity was not found with any other literature sources. © 1993 Academic Press, Inc.

It is important that town gas possess a smell, so that accidental carbon monoxide poisoning can be avoided as far as possible. Tetrahydrothiophene (THT) has been used for this purpose. In the United States, three types of odorant have been used: mercaptans, aliphatic sulfides, and THT, which is chemically stable, economical, and easily added to town gas. In the Matsumoto City area in Japan, tertiary-butyl-mercaptan is added as an odorant to the town gas; however, there is little practical information regarding the constituents and the olfactory fatigue of the odorant in the town gas.

Characterization of trace amounts of odorants in air in an ICU room (ca.257m2) was carried out by gas chromatography and atmospheric pressure ionization-mass spectrometry (API-MS). The concentrations and odor recognition threshold values of the detected odorants, acetaldehyde, ethanol, n-butyric acid, iso-valeric acid and n-valeric acid are as follows: 44.7 ppb and 15 ppb; 19710 ppb and 6100 ppb; 0.50 ppb and 0.4 ppb; 0.45 ppb and 0.4 ppb; 0.67 ppb and 0.5 ppb, respectively. The detected concentrations of these odorants were significantly higher than the odor recognition threshold values. The compounds may, therefore, be responsible for perception of such odors as mixed odors, body odor, and faint or recognizable alcoholic odor, disinfectant odor, and sour, pungent, and goat odors.

The purpose of this paper is to compare the published odor threshold values of six odorants. In Japan, all of the odor threshold values used in the Offensive Odor Control Law (enacted in 1972) were determined in an odor-free room (4 m3) by a trained panel (20 men, ages 30-45 years who were perfumers) who sniffed the odors directly and made absolute judgments of odor quality and intensity. In The Netherlands, sensorial odor concentration measurements were made with an olfactometer in a mobile sniffing car with eight panelists, four men and four women, ages 18-40 years. Such presentations are repeated with different dilution ratios. Comparison of the threshold data for the six different compounds given as the barely perceptible concentration level revealed striking similarities for hydrogen sulfide (in Japan 0.0005 ppm/in The Netherlands 0.0003 ppm), phenol (0.012/0.010), styrene (0.033/0.016), toluene (0.92/0.99), and tetrachloroethylene (1.8/1.2) but not for m-xylene (0.012/0.12). Such a similarity was not found with any other literature sources.

Characterization of trace amounts of odorants in the Shinshu University School of Medicine Hospital ICU room (ca.257m2) air was carried out by gas chromatography and API-Mass spectrometry. The main component of the oxygenates in the ICU air was ethanol, 3.53ppm, however, the data was less than the odor recognition threshold value (6.1ppm).

The gas chromatographic (GC) determination of the sulphur compounds in town gas (in the Nagoya area) was studied by using a flame-photometric detector (FPD) and the cold-trap method with liquid oxygen. The column packings used were 25% TCEP on Shimalite (AW, DMCS), 25% TCP on Shimalite (AW, DMCS), 10% PPE on Shimalite TPA, Porapak Q and silica gel. The major components identified were carbonyl sulphide, hydrogen sulphide, carbon disulphide, thiophene and tetrahydrothiophene (THT). The identities of thiophene and THT were also confirmed by GC combined with the use of a quadrupole mass spectrometer. The average concentrations and standard deviations of thiophene and THT were 8.8 +/- 1.8and 124 +/- 35 ng per 0.051, respectively. The latter value corresponds to 0.7 ppm, which is relatively high for the concentration of an odorant.

A new fully automated thermal desorption-gas chromatographic(GC) system has been developed. Dynamic trapping of the thermally desorbed volatile organic components from a given solid sample is followed by selective stripping of the desired range fraction into a GC separation column. The functions of two associated electromagnetic valves, three independent heaters, a cooling fan and the temperature programming of the GC-column oven are all controlled by a microcomputer through an electronic interface. With this analytical system, rapid and sensitive determinations of trace organic components can be carried out for various practical samples such as airborne particulates, carbon blacks, medical plaster sheets and cured insulating polymers.

Eight phenols, phenol, o -, m - and p -cresol, 2,3-, 2,5-, 3,4- and 3,5-xylenol, were converted into the corresponding bromophenols by reaction with bromine. The optimum conditions for the bromophenol derivative formation of 10 -8 mol of each phenol in 1 ml of ethanol were as follows: mol ratio (bromine/phenols), greater than 400; reaction temperature, room temperature; reaction time, 4 h. The minimum detectable amount of the bromophenols with an electron capture detector was about 0.01 ng, which is about 100 times less than the minimum detectable amount of the non-bromine-containing phenols.

Summary The gas chromatographic separation of 22 carbonyl compounds as their 2,4-dinitrophenylhydrazones was investigated using glass capillary columns. Complete separation of the 2,4-dinitrophenylhydrazones of ten aliphatic aldehydes, eight aliphatic ketones and four aromatic aldehydes was obtained, except for the derivatives of n -valeraldehyde and isobutyl methyl ketone, whose peaks overlapped, and the o - and m -tolualdehyde derivatives, which were poorly separated. The optimum conditions were as follows: stationary phase, SF-96; column size, 20 m × 0.25 mm I.D. ; column temperature, 200-240°; injection and detector temperatures, 280-290°; carrier gas flow-rate, helium 1.0-1.2 ml/min or nitrogen 1.1-1.2 ml/min. The method was applied to the analysis of aliphatic carbonyl compounds in car exhaust fumes and cigarette smoke.

The gas chromatographic (GC) determination of trace amounts of β-methylmercaptopropionaldehyde (methional) in the free form using a flame photometric detector (FPD) was investigated. The GC conditions were as follows: stationary phase, 6% DEGS; support, Chromosorb W HP (80–100 mesh); glass column, 2 m X 3 mm I.D., column temperature (programming), holding for 1 min at 100°C, heating the column oven at a rate of 10°C/min from 100 to 190°C, maintaining this temperature for 20 min and then cooling to the initial temperature; carrier gas, nitrogen, flow-rate, 60 ml/min; flow-rates of hydrogen and air for the FPD, each 40 ml/min. The minimum detectable amounts for the methional were ca. 0.3 ng; the repeatabilities of retention times and peak areas (measured as intergrator counts) at 1-ng level of the compound were less than ca. 1.5% and ca. 15%. The percentage recovery in the concentration method by bubbling the nitrogen carrier gas (0.2 1/min, at 28°C) through the standard solution of methional (at 1 ng per μl ethanol) from 10 to 0.5 ml was ca. 72%; however, the percentage recovery of the standard solution (at 10 ng/μl ethanol) after 10 l of the laboratory air had been passed through the impinger containing the standard solution at a rate of 0.5 l/min was 97.5%. The method was applied to the determination of methional in air over waste water from a corn starch factory.

A simple and rapid gas—liquid—solid chromatograhic method for the determination of trace concentrations (at ppb * levels) of 11 phenols in air has been developed, using a Tenax-GC precolumn and a Tenax-GC plus alkaline precolumn. The phenols were identified and quantitated from the differences between the chromatogram obtained using the Tenax-GC precolumn and that obtained using the Tenax-GC plus alkaline precolumn. Complete separation was achieved within ca . 7 min. No evidence was found for the interference of certain acidic compounds, such as lower fatty acids (C 2 C 7 ) and mercatans (C 5 C 7 . The method was applied to specimens of ambient air near a phenolic resin factory, and of urban air in the Nagoya area.

The selective and sensitive gas chromatographic determination of trace amounts of styrene was studied. Styrene was converted into styrene dibromide by reaction with bromine, and the latter was detected with an electron-capture detector. The minimum detectable amount of the dibromide was about 0.01 ng and the sensitivity to the dibromide was about 500 times higher than the sensitivity of a flame-ionization detector to the styrene monomer. Dodecene-I and o- and m-cresol gave the greatest interference, but the cresols could easily be removed by reaction with a small amount of a dilute aqueous alkaline solution. The application to a practical specimen, namely urban air, is described.

A simple circular odor chart is proposed for the explanation of the relationship between sensory responses (to odor quality and intensity) to odors and chemical analysis data of the odorants responsible for each odor discharged from thirteen odor sources. The odorants were classified into eight odorant groups and were analyzed by a systematic gas chromatographic (GC) technique. The characterization of the trace amounts of the odorants was carried out by using the values of a new proposed unit (pOU) based on the ratio of detected concentration to recognition threshold value. The calculated pOU values of the eight groups were plotted in circular charts. It was found that the shape and size of each circular odor chart represent the quality and the intensity of each odor.

The simultaneous gas-chromatographic separation of a mixture of 14 lower fatty acids, 11 phenols and 7 indoles was performed by using a fused silica glass capillary column of Carbowax 20M (50 m × 0.2 mm i.d., Carbowax 20M deactivated). Complete separation of the mixture was obtained, except for the peaks of phenols and o-cresol, o-ethylphenol and 3,5-xylenol and pelargonic acid, 2,3-xylenol and 1,2-dimethylindole, whose peaks overlapped, and 2- and 3-methylindoles, which were poorly separated. The optimum conditions are as follows: column temperature, held for 1 min at 100 °C; column oven, heated at 4 °C min–1 from 100 to 220 °C, maintained at 220 °C for 9 min for standard compounds or 29 min for sample specimens, then cooled to 100 °C; and carrier gas (nitrogen) flow-rate, 0.97 ml min–1. The method was applied to the analysis of the lower fatty acids, phenols and indoles in cat and human faeces and non-smoker saliva.

Determination of the sulfur compounds in the exhaust gas from a cellophan factory were studied by gas chromatography equipped with liquid oxygen cold trap, and with flame photometric detector.The sulfur compounds, i.e., COS. H2S, CS2 were identified with the use of TCEP and TCP columns, and the ranges of the detected concentrations were as follows; COS 8-14ng/0.01l, H2S 26-48, CS2 720->1, 000 in non irradiation, respectively (Table-1).Light irradiation of natural sunlight (0.6cal cm-2 min-1, by thermocouple type) effect of the exhaust gas were produced COS (ab. 23ng/0.01l), SO2 (ab. 800ng/0.01l) but not H2S (Table-2).

The determination of the concentrations of trace amounts of 46 odorants prepared at odour threshold levels (in parts per billion) in air in a 10-m3 stainless-steel odour test room was investigated by gas chromatography using two pre-concentration methods, namely cold trapping with liquid oxygen and room-temperature adsorption trapping with porous polymer beads, such as Tenax-GC or graphitised carbon black coated with a small amount of stationary phase (SP-1000 + orthophosphoric acid)(0.3 + 0.3% on Carbopack B, 60–80 mesh). The 46 odorants tested were four sulphur compounds, ten lower aliphatic carbonyl compounds, an aromatic hydrocarbon, seven lower aliphatic mono-alcohols, eleven phenols, six lower aliphatic carboxylic acids and seven indoles. The recoveries of the odorants having boiling-points of less than about 150 °C were quantitative, but those having boiling-points of more than 160 °C gave recoveries of about 50%, except for the phenols, which had much lower recovery levels.

A simple and rapid gas-liquid-solid chromatographic method for the determination of trace amounts of the lower aliphatic carbonyl compounds (C2—C5) in free forms in the exhaust gases from some odour sources was developed using the cold-trapping method with liquid argon. In the main analytical column the conditions were as follows: stationary phase, 1,2,3-tris-2-cyanoethoxypropane (TCEP), 5%; support, Carbopack B (60–80 mesh); glass column, 1.5 m × 3 mm i.d.; column temperature, 70 °C; carrier gas, nitrogen, flow-rate 50 ml min–1.In the cold-trapping pre-column the conditions were as follows: stationary phase, TCEP (25%); support, Shimalite (AW, DMCS)(60–80 mesh); glass column, 31 cm × 4 mm i.d., operating temperature for trapping, –186 °C (liquid argon); operating temperature for injection of the condensed sample into the gas chromatograph, increased from –186 °C to 120 °C in 3.5 min and maintained at this temperature for 30 s. The peaks due to lower aliphatic carbonyl compounds were identified by the disappearance method using a reaction pre-column of 2,4-dinitrophenylhydrazine (0.05 g)-orthophosphoric acid (0.1 ml) on glass beads.The method has been applied to the determination of lower aliphatic carbonyl compounds in real samples (the exhaust gases from a poultry manure dryer, a metal paint dryer and a pig manure dryer). The volume of sample gas required is as low as about 0.41 and the method is sensitive [detection limit about 10 p.p.b. (parts per 109)] and rapid (for the concentration and analysis of one sample about 30 min are required). The coefficient of variation is less than 10%. Propionaldehyde, acrolein and acetone (compounds each with three carbon atoms) were completely separated within about 7 min without tailing.

The odorants discharged from nine odour sources were classified into eight compound groups and were analysed by a systematic gas-chromatographic technique. The characterisation of trace amounts of the odorants was carried out by using the values for new proposed units (pOUm, pOUa, logOU, OUt and OU; all terms are dimensionless) based on the ratio of the detected concentration to the odour recognition threshold concentration. The graphical representation of these data is effective for rapid recognition of the whole state. A polar co-ordinate pattern display was also proposed for the explanation of the relationship between odour characteristics (odour quality and intensity) and chemical analysis data of the odorants responsible for each odour discharged from nine odour sources. The calculated pOUm and pOUa values of eight odorant groups were plotted on polar co-ordinate circular odour charts. These charts illustrated a characteristic pattern and it was found that the shapes and sizes of each odour chart could characterise the quality and intensity of each odour from the nine odour sources. This was confirmed by investigating examples of processes or factories belonging to the nine odour sources.

The gas-chromatographic determination of trace amounts of the lower fatty acids (C2—C5) in ambient air near and in the exhaust gases of some odour sources was investigated. The sample for the gas-chromatographic determination was prepared by trapping in a pre-column packed with FFAP + orthophosphoric acid (H3PO4) on Carbopack C at 25 and 30 °C. The lower fatty acids were identified and quantitated from the difference between the chromatograms obtained using the FFAP + H3PO4 pre-column and that obtained using the FFAP + H3PO4 plus an alkaline pre-column. The method has been applied to the analysis of lower fatty acids in practical specimens, namely the ambient air near accumulated poultry manure, in a pig pen and a fish meal factory, and in the exhaust gases from a corn starch manufacturing factory and from a poultry manure dryer. The sample volume is as low as about 0.4 l and the method is sensitive (detection limit about 0.5 p.p.b.) and rapid (including the concentration and analysis of one sample, about 15 min are required). The coefficient of variation is less than 6%. This sensitivity and precision are adequate for use in odour pollution analysis.