• Toxicological Research
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• v.17 no.1
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• pp.33-39
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• 2001

To evaluate the skin toxicity oj topical toluene application, toluene (35 mg/$cm^2$) was sequentially applied to the portion rat skin for five days. The topical toluene application resulted in increased xanthine oxidase activity and CYP content, and significantly decreased superoxide dismutase and glutathione peroxidase activities at five days in rat skin. Especially catalase activity was remarkably decreased in toluene-applied rat skin. And benzylalcohol dehydrogenase activity showed also a significant decrease in toluene-applied skin. On the other hand, histopathological ultrastructural examination revealed disrupted epidermal basement membrane, rared intercellular adhensions and degenerated keratin layer due to topical toluene application. Increased deposit of cerrous perhydroxide resulted from reaction with $H_2O_2$was abserved in toluene-treated animals. These results indicate that oxygen free radical may be responsible for ultrastructural changes in skin tissue by toluene application to rat skin.

• Korean Chemical Engineering Research
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• v.54 no.5
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• pp.665-670
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• 2016

This study deals with the possible degradation of toluene and acetic acid when subjected to cell-free enzyme system from the toluene degrading bacteria Pseudomonas putida and acetic acid degrading bacteria Cupriavidus necator. P. putida produces toluene dioxygenase only under the existence of toluene in culture medium and toluene is degraded to cis-toluene dihydrodiol by this enzyme. C. necator produces acetyl coenzyme A synthetase-1 and converts acetic acid to acetyl CoA in order to synthesize ATP to need for growth or PHA which is biodegradable polymer. In case of toluene degradation, the experiment was conducted before and after production of toluene dioxygenase as this enzyme, produced by P. putida, is an inducible enzyme. Toluene was detected using gas chromatography (GC). Similar amount of toluene was found in control group and before production of toluene dioxygenase (experimental group 1). However, reduction in toluene was detected after the production of toluene dioxygenase (experimental group 2). Acetic acid was detected through application of gas chromatography-mass spectrometer (GC-MS). The results showed the acetic acid peak was not detected in the experimental group to apply cell-free enzyme system. These results show that the cell-free enzyme system obtained from P. putida and C. necator retained the ability to degrade toluene and acetic acid. However, P. putida needs to produce the inducible enzyme before preparation of the cell-free enzyme system.

• Journal of Life Science
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• v.9 no.6
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• pp.715-721
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• 1999

The biodegradative potentialities of a toluene-tolerant Pseudomonas sp. BCNU 154, isolated from waste water, were investigated. Among 16 aromatic substrates tested, cumene, cyclohexane, ethylbenzene, p-xylene, m-xyene, toluene and diphenylether were metabolized. Pseudomonas sp. BCNU 154 degraded aerobically toluene, ethylbenzene, p-xylene and cumene. With toluene competitive degradation occurred after 12 hours, but with p-xylene and cumene, and with ethylbenzene, 90 and 75% degradation occurred after 12 hours of incubation, respectively.

• Toxicological Research
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• v.31 no.1
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• pp.25-32
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• 2015

The objectives of this study were to investigate the individual characteristics, lifestyle habits, exposure levels, and genetic diversity of xenobiotic-metabolizing enzymes involved in toluene metabolism in Korean and foreign workers exposed to toluene at a manufacturing plant. This study was conducted to determine the effects of culture or ethnicity on toluene metabolism. The results showed that blood and urinary toluene concentrations were dependent on the level of exposure to toluene. We analyzed the correlation between toluene metabolism and genetic diversity in glutathione S-transferase (GST) (M1), GSTT1, and cytochrome p-450 (CYP) $2E1^*5$ as well as lifestyle habits (smoking, drinking, and exercise habits). The results revealed significant correlations between toluene metabolism and GSTM1 and GSTT1 genetic diversity, as well as smoking and exercise.

• Biomedical Science Letters
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• v.5 no.1
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• pp.67-74
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• 1999

To investigate the effect of the circadian variations on the toluene metabolism, 50％ toluene in olive oil (0.2 m1/100 g body weight) was intraperitoneally administered to the rats every other day for 6 days both in the night; 24:00 and the day; 12:00. Each group of animals was sacrificed at 8 hr after last injection of toluene. Hepatic microsomal aniline hydroxylase activity was more increased in control rats of night phase than those of day phase. On the other hand, the activities of hepatic benzylalcohol dehydrogenase in control rats of night phase showed the similiar value with that in those of day phase and in case of toluene treatment, these enzyme activities in rats of night phase were rather more decreased than those of day phase. Furthermore, hepatic benzaldehyde dehydrogenase activities were more or less higher in the control rats of night phase than those of day phase and by toluene treatment, enzyme activities of rats of night phase were somewhat decreased than those of day phase. in vitro, benzylalcohol or benzaldehyde inhibited the activities of benzylalcohol or aldehyde dehydrngenase prepared from the rats liver supematant. There were no differences in urinary hippuric acid contents between the night phase and day phase both in the control and toluene treated group. The increasing rate of liver weight per body weight (％), serum xanthine oxidase activities were higher in rats of night phase than in those of day phase by toluene treatment. In conclusion, these results indicate that the producing rate of benzylalcohol and benzaldehyde from toluene may be higher in rats of night phase than those of day phase.

• Toxicological Research
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• v.11 no.2
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• pp.289-294
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• 1995

This study was designed to observe the effect of tohiene pretreatment on leukocyte variation in whole blood and the oxygen free radical generating, scavenging enzyme activities in neutrophil of bacteria infected rats. Toluene was administered 7 times intraperitoneally at levels of 9.45 mM/kg body weight to the rats and then infected with S. aureus $2\times10^7$ cfu/ml. The toluene treated-rats showed the significantly decreased numbers of lymphocyte and monocytes, but the similiar numbers of neutrophils with the control. Furthermore the increased neutrophils in blood of bacteria infected rats were reduced by the toluene pretreatment. Concomitantly the increased activities of xanthine oxidase and superoxide dismutase in neutrophil of bacteria infected rats were also decreased by the toluene pretreatment. On the other hand, injection of benzaldehyde to rats also led to similiar results in the count of leukocytes, xanthine oxidase and superoxide dismutase activities of neutrophil with those of toluene treated rats. These data suggest that toluene and its intermediate metabolite, benzaldehyde influence on the phagocytosis and defence mechanism of neutrophil.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.3
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• pp.289-294
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• 1996

To evaluate an effect of acute ethanol pretreatment on the liver injury in toluene-treated rats, toluene(50% in olive oil) was intraperitoneally given four times at 0.3ml/100g body weight at interval of one day to the ethanol-pretreated rats(0.3ml of 50%/100g body weight). The increasing rate of liver weitht per body weight(%), serum levels of alanine aminotransferase (ALT) activity, liver lipid peroxide content was higher in toluene treated rats pretreated with ehtanol than those treated with toluene alone. Concomitantly the hepatic glucose-6-phosphatase activity was increased whereas glutathione content was decreased by ehtanol pretreatment before toluene administration in rats. In case of direct administration of acetaldhyde or benzaldehyde to the rats, the liver weitht per body weight(%) and serum levels of ALT activity were almost higher than the control group. There results indicate that the toluene treated rats showed the reversible injury of liver and intensified. however, by the ethanol treatment.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.4
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• pp.297-305
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• 1997

The experimental study by use of SPCP was fulfilled to remove toluene emitted from various industrial processes. First of all, discharge characteristic was experimented as the change of applied voltage and frequency. Then toluene removal characteristic was tested with the analysis of by-products. As a result, optimum electrical discharge condition was from 20.0 kHz to 25.0 kHz of frequency and from 3.5 kV to 4.0 kV of voltage range. The variation of applied voltage had a more important effect on the removal characteristic of toluene than the frequency variation. The toluene removal efficiency was proportioned to ozone concentration and retention time on discharge plate. It was dropped as increase of toluene concentration, but total treated volume of tolene per power consumption was high. The decomposed toluene was transformed to $CO, CO_2$ and particulates, and the rate of transformation to particulates was higher than CO and $CO_2$ at high toluene concentration. Particulates were increased from 0.017 $\mum$ to 0.3 $\mum$ range of size distribution.

• Toxicological Research
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• v.12 no.2
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• pp.237-241
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• 1996

To study an effect of toluene administration on the toluene metabolism in rats liver previously fed a low (casein 7%, LP) or standard (casein 20%, SP) protein diet, toluene (50% in olive oil) was given at 0.2 ml per 100 g body weights once daily during 4 days to the male rats. The content of hepatic cytochrome P-450 was higher in rats fed SP than those fed LP. The hepatic benzylalcohol dehydrogenase activity was higher both in toluene-treated rats and its control group fed SP than those fed LP. The hepatic benzaldehyde dehydrogenase activity was somewhat higher in rats fed SP than those fed LP. In the case of toluene treatment, the increasing rate of hippuric acid contents to the control group were higher in rats SP than those fed LP. In conclusion, it is likely that the metabolic rate of toluene would be higher in rats fed SP than those fed LP.

• Biomolecules & Therapeutics
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• v.3 no.1
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• pp.91-96
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• 1995

The effects of toluene inhalation on the contents of amino acid neurotransmitters in rat brain were investigated and blood toluene concentrations inducing changes of behavior and amino acid neurotransmitter contents in rat brain were observed. Male wistar rats were exposed to toluene vapor (single dose : 1700, 5000 and 10000 ppm for 2 hrs, repeated dose : 1700 and 5000 ppm for 2 hrs/day$\times$6 days). Toluene concentrations in blood and the inhalation chamber were assayed by GC with headspace sampler. HPLC method following PITC derivatization was used to measure the amino acid contents in brain tissues such as frontal cortex, caudate, hippocampus, cerebellum and brain stem. Glutamic acid and aspartic acid levels were increased by single inhalation of toluene (5000 ppm) in all the brain areas assayed in this experiment. In caudate and cerebellum, taurine levels were decreased by single inhalation of low dose toluene (1700 ppm), but increased by repeated administration. At high blood toluene concentration, GABA levels were increased in all the brain areas assayed in this experiment and the increasing extents of inhibitory amino acid contents measured in caudate and hippocampus were greater than those of excitatory amino acids. These results suggest that the changes of amino acid neurotransmitter contents in brain by exposure to toluene may modulate toluene-induced behaviors.