This is a review on environmental pollution of polychlorinated dibenzo-p-dioxins and dibenzofurans, of which some isomers are very toxic to some animals. Major sources of these compounds are impurities in chlorinated chemicals and chemical wastes and contaminants in ash and gas from various incinerators and heating facilities. The compounds, thus produced, polluted the environment of air, water and soil as well as plants, fish, animals and even humans at very low levels.

View full abstract

Ion chromatography (IC) with conductivity detection, which was introduced in 1975, has become widely used for the simultaneous determination of inorganic and organic ions. On the other hand, photometric ion chromatography (PIC) based on the difference of absorbances of sample and eluent (mobile phase) species has attracted much attention in the recent field of IC, since this technique has potential advantages over IC methods with conductivity detection. This technique which allows IC on a conventional single column HPLC system with an absorbance detector gives compatible sensitivity to conductivity detection. This paper deals mainly with indirect PIC methods performed by both ion exchange and reversedphase modes, where non-UV-absorbing ions are detected as positive and negative peaks by using UV-absorbing ions in the eluent (mobile phase). The features of PIC have been reasonably well known, but it is necessary to understand principles and conditions of PIC for the effective use of this technique. This paper reviews a number of significant reports which deal with the optimisations of separating column, eluent (mobile phase), detection wavelength, sensitivity and restrictions of PIC with its applications. It is also the purpose of this paper to discuss alternative methods and innovations of PIC.

View full abstract

A gas chromatographic method was developed for the determination of n-dodecylguanidine hydrochloride used as a sanitary finishing agent in fabrics. The analytical procedure is as follows : the fabrics were refluxed in 80% methanol solution containing 0.5% of sodium hydroxide for 1 h. The mixture was filtered and the filtrate was made up to 50 ml with methanol. The n-dodecylguanidine was obtained from an aliquot of the sample solution by extraction with chloroform under alkaline conditions and then derivatized to 2-n-dodecylamino-4, 6-dimethylpyrimidine by refluxing with acetylacetone for 1 h in toluene. The reaction mixture was evaporated to dryness under reduced pressure. The residue was dissolved in ethanol. The pyrimidine derivative was measured by gas chromatography with a column of 5% diethyleneglycol succinate on Chromosorb W AW. This method was applied to the determination of n-dodecylguanidine hydrochloride in commercial men's socks and other textile products.

View full abstract

We established a rapid analytical method for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and Polychlorobenzenes (PCBzs) in samples of fly ash, bottom ash and sludge from municipal domestic and industrial waste incinerators. It was essentially consisted of hydrochloric acid treatment, benzene refluxing extraction and micro-silicagel and alumina column chromatography. The hydrochloric acid treatment was effective for the extraction of PCDDs and PCDFs from fly ash samples. The introduction of benzene refluxing extraction brought a considerable time saving (ca. 19-31 h) in comparison with the conventional soxhlet extraction. In addition, the scale-down and combination of silica gel (1g) and alumina column (1g) gave sufficient purifications for analytes, and reducted remarkably the time in process of purification.

View full abstract

By the use of reversed phase high performance thin layer chromatography, most cannabis acids were able to be separated from neutral cannabinoids (CN) simultaneously. Therefore, the following field-test for cannabis has been developed ; cannabis were extracted with acetone for 2-3 min, developed in acetonitrile for 5 min, dipped in a color-producing reagent where Echtblausalz B was suspended in a solution of sodium hydroxide for one second. This method made it possible to distinguish clearly the types of cannabis with different CN, CBDA species, native varieties and hybridized varieties. Moreover, the results agreed very closely with those obtained by the conventional GC method.

View full abstract

Casein agar plate method for protease assay was developed by the method of Cheeseman with a slight modification. With this modified method, 1μg-1 mg/10μl or 10μg-1 mg/0.1 ml of trypsin was successfully determined and the sensitivity of the method was about 10 times higher than that of the original method. This is one of the simple method for the determination of neutral and alkaline protease activity and was found to be applicable to the field of biochemical study. This method is shown to be very suitable for the measurement of activity change observed when protease is treated with various inhibitors and antiserum, respectively. Especially, the results of inhibition test with protease inhibitors by this method agreed well with those obtained by the conventional method determining the remaining protease activity after preincubation of the inhibitor with protease solution. In the clinical analysis with experimental animals, the method was successfully applied for the detection of trypsin in fecal specimen and duodenum Juice. Furthermore, it was also useful for check of routine protease assay of each fraction isolated by column chromatography.

View full abstract

Although a significant number of polynuclear aromatic hydrocarbons (PAHs) have been known to be carcinogens, there have been few publications on their distribution in sediments from small streams which are directly affected by anthropogenic pollution. Therefore, distribution of 8 PAHs, i.e. pyrene (Py), fluoranthene (Fl), benzo [a] anthracene B [a] A, benzo [k] fluoranthene B [k] F, benzo [b] fluoranthene B [b] F, benzo [a] pyrene B [a] P, benzo [ghi] perylene B [ghi] P and perylene (Per), in sediments from 11 small streams in Niigata Prefecture were measured and compared with those of the Shinano River. B [a] P concentration was correlated to the other 6 PAHs except for Per. Concentrations in sediment of Py, Fl, which were the most abundant in the 8 PAHs, and B [a] A, which existed in the least, were ranged from 2.0 to 870, 1.8-869 and 0.2-176 ng/g dry weight, respectively ; B [a] P and Per concentrations were 0.4-293 and 0.7-435 ng/g dry weight, respectively. PAH levels at downstream were higher than those at upstream except for in 2 small streams. Except for Per, every PAH-concentrations per ignition-loss was extreamly high at the places where industrial wastewater or treatment sewage flowed, whereas they were not so high where domestic wastewater flowed. The sampling sites appear to be divisible into 8 groups by cluster analysis ; each group was characterized by total-PAHs per ignition-loss, B [a] P per ignition-loss, Per per ignition-loss and linear-alkylbenzenesulfonates per ignition-loss.

View full abstract

Drugs and pesticides (129 compounds) of abuse have been analysed simultaneously by a capillary gas chromatograph with dual fused-silica column having different polarity and retention index data have been compiled for these compounds. By installing two differently coated columns with a split adapter in the same injector and connecting these column ends to flame ionization detectors (FID), the simultaneous gas chromatographic analysis of these compounds was accomplished. Two fused silica columns were CBP-1 and CBP-10 (0.2 mm i.d.×50 m, film thickness 0.25μm). The column temperature increased from 100°C to 320°C at 10°C/min, the detector and injector temperature was 280°C. Discriminating power (DP) was 0.993 with combination of two columns (error factor=30). Retrieval system was developed through the use of a retention index library and the program of this system was written with BASIC. A summary of the BASIC program used for retention index calculation and library seach is included. Furthermore, it was possible to estimate the molecular weights and to specify compounds with retention index by using this system.

View full abstract

The growth inhibition test method was studied for the hazard evaluation of chemicals to microorganisms which play an important role in an aquatic ecosystem. As a source of microorganisms, "standard activated sludge" which is distributed from Chemical Inspection and Testing Institute, in Tokyo was used and the degree of growth was measured by a turbidity. On eleven chlorophenols tested, 24 h-EC₅₀ values were correlated with 3 physico-chemical parameters, i.e., n-octanol/water partition coefficient (log Pow), dissociation constant (pKa) and Hammett constant (Σσ). Though the toxicity increases from monochlorophenols to trichlorophenol except for chlorophenols substituted at 2, 6-positions, 2, 3, 4, 6-tetra-and penta-chlorophenol were less toxic than 2, 3-, 3, 5-dichloro-and 2, 3, 4-trichlorophenol. Quantitative structure-activity relationship (QSAR) studies show that partition coefficient, a parameter of lipophilicity, gives the best correlation with 24 h-EC₅₀ values by using square of log Pow. Among the isomers of chlorophenols having the same numbers of chlorine atom, ortho isomer appears to be less toxic than meta and para isomers. With regard to several chlorophenols, 24 h-EC₅₀ values were determined by the respiration inhibition method and ATP measurement method, and compared with 24 h-EC₅₀ values by the growth inhibition method shown above. It is suggested that the respiration inhibition method is less sensitive than the growth inhibition method. Furthermore, a relation ship between toxicity and biodegradability was studied by the performance of microbial degradation test at low concentration where the test chemical did not inhibit the growth of microorganismsand it is suggested a few chlorophenols which are persistent at concentration of 100 mg/l can be degraded at a level of 10 mg/l.

View full abstract

Test conditions for fish early life stage toxicity (ELST) of U.S.EPA were examined and established by use of Japanese Medaka, Oryzias latipes, as a test species. The semi-static method by renewing test water in every 48 h was adopted instead of EPA's flow-through test system. After the establishment of some testing conditions such as collection of embryo and feeding for juvenile, embryos and larvae after hatch were exposed to 2, 4-dichlorophenol (2, 4-DCP) for 40 d for the evaluation of maximum acceptable toxicant concentration (MATC). Both hatching of embryos and survival of juveniles were significantly reduced by exposure to 2, 4-DCP of 0.63 mg/l, whereas the growth rate was not affected at the highest concentration tested, 1.25 mg/l. Therefore, both hatching of embryo and survival were more sensitive indicators than the growth of juveniles for toxic effects of 2, 4-DCP. On the basis of the above results, MATC for Japanese Medaka was estimated to be 0.32-0.63 mg/l and this value almost agreed with the MATC value for fathead minnow, 0.29-0.46 mg/l and ELST is much more sensitive than acute toxicity to Medaka, 96 h-LC₅₀ of 6.3 mg/l. It is concluded that Japanese Medaka is a good test species for ELST test in the simple semi-static test water renewal system.

View full abstract

When the expiratory excretion of ¹⁴CCl₄ and its metabolites were measured in ¹⁴CCl₄ administered mouse and rat, a clear species difference was observed as follows : (1) Excretion of ¹⁴CO₂ proceeded faster in mouse than in rat. About 45% and 21% of the radioactivity were excreted in the expired gas in mouse and rat, respectively, in 10 h. (2) ¹⁴CCl₄ and its metabolites (fat-soluble) excreted in the expired gas in mouse and rat were 16% and 57% of the administered dose, respectively, after 10 h. (3) The excretion of the total ¹⁴C in mouse and rat were about 60% and 77%, respectively, after 10 h.

View full abstract

In order to establish efficiently the operating conditions of gas chromatography (GC-FPD) for organophosphorus pesticides, relative retention times (RRT) to parathion and appraisal of separation for 34 pesticides were investigated on serveral liquid phases. Seven liquid phases that were selected on the basis of McReynolds constant were OV-1 as low polarity, DC-200+EPON 1009, OV-17, QF-1, XE-60 as moderate polarity and PEG-20M, DEGS as high polarity. It was found that moderately polar liquid phases such as DC-200+EPON1009, OV-17, QF-1 and XE-60 were most suitable for the analysis of these pesticides. Detection limits were in the range of 0.05 to 10 ng for the most part of them. Polar pesticides were fine for polar liquid phases such as XE-60, DEGS. Combined application of these liquid phases in which RRTs turn over each other should be effected for complete certification on GC analysis. Next, RRTs of 34 pesticides were plotted on the diagram with McReynolds constant to vertical line and RRT to horizontal line. By practical use of this diagram, it would be easy to grasp the character of an organophosphorus pesticide, to infer the behavior of one among liquid phases. Besides, suitable operating conditions of GC for the determination of a pesticide will be easily chosen due to this RRT diagram.

View full abstract

A simple cleanup method with Sep-Pak silica cartridge (Waters Associates) was developed for the determination of linear alkylbenzene sulfonates (LAS) in sediment by high performance liquid chromatograph (HPLC) equipped with a fluorescence detector. The Sep-Pak silica cartridge treatment was extremely effective to remove co-existing interferences which appeared as an unresolved peak to the peaks for dodecylbenzene sulfonates in liquid chromatograms. Ten g of a sediment sample was extracted twice with 10 ml of methanol using a ultrasonic apparatus. After centrifugation, the combined extract was concentrated and dried up. The residue was dissolved in 2 ml of chloroform ; the chloroform layer was loaded to a Sep-Pak silica cartridge. After 10 ml of chloroform was passed through the cartridge, LAS was eluted with 4 ml of methanol. The eluate was concentrated and dried up. The residue was dissolved in 2 ml of methanol-water (7 : 3) for HPLC determination. Recoveries and coefficients of variations of LAS (0.938-11.7μg/g) added to 10 g of sediment were 89.6-108% and 7.0-7.3%, respectively ; the minimum determinable amount of LAS was 5 ng/g. This method was applied to determine LAS in sediments from small streams and the Shinano River ; the co-existing interferences in sediments were removed perfectly by the proposed cleanup method.

View full abstract