Sukeo Onodera

Chemical changes of organic compounds in chlorinated water. XIII. Gas chromatographic-mass spectrometric studies of the reactions of Irgasan DP 300 [5-chloro-2-(2,4-dichlorophenoxy)phenol] with chlorine in dilute aqueous solution.

The reactions of Irgasan DP 300 with chlorine in water were investigated by means of gas chromatography (GC) and GC-mass spectrometry. Irgasan DP 300 was shown to produce dichloro- and trichloro-2-(2,4-dichlorophenoxy)phenols in chlorine-treated water, followed by the decomposition of these intermediates to chlorophenols. No polychlorinated dibenzo-p-dioxins were detected in chlorine-treated Irgasan DP 300 solutions. The production of some of these compounds is dependent on the number of equivalents of chlorine per mol of compound and on the reaction pH.

Simultaneous determination of phthalate di- and monoesters in poly(vinylchloride) products and human saliva by gas chromatography-mass spectrometry.

A gas chromatographic-mass spectrometric (GC-MS) method using selected ion monitoring (SIM) is described for the simultaneous determination of phthalate di- and monoesters in poly(vinylchloride) (PVC) products. The method consists of the following four procedures; (1). liquid-liquid extraction with ethyl acetate from the acidified aqueous homogenates of the PVC products, (2). esterification with trimethylsilyldiazomethane (TMSD) and methanol, (3). clean-up using Florisil column chromatography and (4). quantitative determination of methylated phthalate monoesters by GC-MS using SIM. The methylated monoesters show a characteristic mass fragment pattern at m/z 163, 149 and 91. The calibration curves for the monoesters were linear from 0.05 to 10 ng (injection volume 1 micro l). Overall recoveries ranged from 86.6 to 94.3%. The limits of detections for these methylated derivatives were in the range of 2.0-5.0 ng/g (S/N=3). This method was applied to phthalate monoesters in PVC toy products. Mono-n-butyl phthalate and mono-2-ethylhexyl phthalate were found at levels of 6.42-11.62 micro g/g and 30.50-41.81 micro g/g, respectively. No monoethyl phthalate, mono-n-hexyl phthalate and monobenzyl phthalate were found in the toy products. The method was also applied to these compounds in human saliva.

Chemical changes of organic compounds in chlorinated water : XI. Thin-layer chromatographic fractionation of ames mutagenic compounds in chlorine-treated 4-methylphenol solution☆

The diethyl ether extract from an aqueous solution of 4-methylphenol after treatment with hypochlorite was mutagenic to the Ames Salmonella test strain TA100 in the absence of liver homogenate. Gas chromatography-mass spectrometry (GC-MS) showed the occurrence of, at least, twenty compounds in the extract: chloro-4-methylphenols, chlorohydroxy-4-methylquinones and chlorinated 4-methylphenol dimers. The diethyl ether extract was fractionated into several fractions by silica gel and polyamide thin-layer chromatography (TLC). The fractionated components were then examined for mutagenicity by means of Ames assays, and were identified by GC-MS. TLC fractionation of the extract revealed that the major components present in the extract are not mutagenic, but minor components (less than 4% of the total extract) are mutagenic. GC-MS analysis indicated the presence of chlorinated 4-methylphenol dimers in the fraction which exhibited the highest mutagenicity.

Characterization and determination of organic compounds in the mutagenic XAD-2 extracts of drinking water

Amberlite XAD-2 extracts, which exhibit mutagenicity in the Ames assays, of drinking water sampled each month during the period from April 1988 to March 1989 were studied in order to characterize and determine the organic pollutants. The major organic pollutants were phthalate ester plasticizers such as dibutyl and di(2-ethylhexyl) phthalate. Several polynuclear aromatic hydrocarbons (PAHs) and the organocholorine pesticide oxadiazon were also identified to be present at low concentrations. The XAD-extractable and chromatographable organic pollutants were found to be composed of PAHs with a mean concentration of 0.136 micrograms/l(ca. 10% of the total amount of organic compounds detected), phthalates with a mean value of 0.405 micrograms/l(ca. 30%) and other compounds with a mean value of 0.845 micrograms/l(ca. 60%). The concentrations and compositions of these organic pollutants were correlated with the effective rainfall content of the river and with the water temperature.

Chemical changes of organic compounds in chlorinated water : IX. Formation of polychlorinated phenoxyphenols during the reaction of phenol with hypochlorite in dilute aqueous solution

Abstract Aqueous phenol solutions were treated with hypochlorite at 20°C under various experimental conditions. Changes in the composition of the chlorination products in water were determined by using gas chromatographic (GC) and GC-mass spectrometric analyses of diethyl ether extracts. Chlorination of phenol in dilute aqueous solution produced a series of highly chlorinated compounds, including chlorophenols, chlorobenzoquinones and chlorinated carboxylic acids. Tentative identifications were also made for other compounds with the following proposed molecular formulae: C 12 H 8 Cl 2 O 2 , C 12 H 7 Cl 3 O 2 , C 12 H 6 Cl 4 O 2 and C 12 H 5 Cl 5 O 2 . On the basis of thin-layer chromatographic and GC behaviour, these compounds are considered to be chlorinated phenoxyphenols. Production of some of these compounds is dependent on the equivalents of chlorine per mole of compound and the reaction pH. These results show that treatment with chlorine of water contaminated with phenolic compounds leads to the production of chlorinated phenoxyphenols.

Organochlorine pesticide residues in green mussel (Perna viridis) from the Gulf of Thailand

Abstract Green mussel ( Perna viridis ) collected from the Gulf of Thailand from May to August 1989 were analysed for the levels of BHCs, DDTs, HCB, aldrin, dieldrin, endrin, heptachlor, and heptachlor epoxide. Concentrations of DDTs, aldrin, and dieldrin were found to be higher than those of other compounds. Heptachlor epoxide, endrin, β and δ isomers of BHC were not detected in any of the samples examined. The levels of organochlorine pesticide residues in green mussel did not exceed the maximum residue limit for aquatic animals as recommended by the Ministry of Public Health in Thailand.

Chemical changes of organic compounds in chlorinated water : XVI. Gas chromatographic—mass spectrometric studies of reactions of tricyclic aromatic hydrocarbons with hypochlorite in dilute aqueous solution

The products of aqueous chlorination reactions of tricyclic aromatic hydrocarbons (fluorene, carbazole, dibenzofuran, anthracene, phenanthrene and some methyl derivatives) with hypochlorite have been determined by gas chromatography-mass spectrometry. They included chloro-substituted, oxygenated (quinones) and hydroxylated (phenols) compounds, and products of addition which were readily formed at ambient temperature. The extent of the reactions was shown to depend on the chlorine dose, the solution pH, the initial concentrations of both compounds and the structures. Monochlorinated compounds and quinones were shown to be present in chlorinated water under the conditions utilized for water treatment.

Gas chromatographic identification and determination of chlorinated quinones formed during chlorination of dihydric phenols with hypochlorite in dilute aqueous solution

This paper describes gas chromatographic identification of chlorinated quinones present in water on the basis of plots of log tR against number of chlorine atoms in the molecule. The plots for each homologous series of chlorinated phenols, hydroquinones (HQ) and p-benzoquinone chromatographed on polar and non-polar columns are found to be linear, with few exceptions. Mono-,di- and trichlorinated quinones are the principal intermediate products during chlorinations of catechol, resorcinol, HQ and methyl-HQ with aqueous hypochlorite. The residual intermediate compounds formed from resorcinol and methyl-HQ are present in higher concentrations in chlorinated water than those of other dihydric phenols.

Mechanism of the biphasic effect of ethylenediaminetetraacetate on lipid peroxidation in iron-supported and reconstituted enzymatic system

The biphasic action of ethylenediaminetetraacetate (EDTA), depending on its concentration, on lipid peroxidation was examined in an iron-supported and reconstituted enzymatic system. In the presence of NADPH-cytochrome P450 reductase and NADPH, Fe(3+)-PPi or Fe(3+)-ADP, though not reducible in the absence of EDTA, was markedly reduced with increasing concentration of EDTA. Lipid peroxidation, in the reconstituted system containing negatively charged liposomes, showed the maximal rate at 0.5 molar ratio of EDTA/iron, but no peroxidation occurred in positively charged liposomes, suggesting production of a positively charged iron complex as the prooxidant. Isotachophoresis indicated production of net-negative charge, EDTA-Fe(3+)-PPi complex, from Fe(3+)-PPi and EDTA at 1.1 ratio of EDTA/iron. The complex quenched Fe(2+)-PPi-supported lipid peroxidation. We suggest that EDTA-iron complexes of different charges are generated, depending on the amount of EDTA in the enzymatic system and, consequently, there is a switch between prooxidant and inhibitory effect at some critical ratio of EDTA/iron.

Aqueous chlorination of tetracyclic aromatic hydrocarbons: reactivity and product distribution

Abstract Reaction of tetracyclic aromatic hydrocarbons (TCAHs) with chlorine in water were investigated by means of a capillary GC equipped with flame ionization detector. TCAHs tested were benz(a)anthracene (B(a)A), benzo(c)phenanthrene (B(c)P), chrysene (Chy), pyrene (Py), and triphenylene (Tri). The reactivity of these TCAHs to chlorine in water were found to be dependent on their structures, indicating a increase in the reactivity with a decrease of their ionization potentials. Mono- and dichlorinated derivatives and oxygenated compounds were identified to be present in chlorine-treated TCAHs solutions under those conditions utilized for water treatment plant.