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1.
C. A. D’Alonzo M.D. Sidney Pell Ph.D. 《Archives of environmental & occupational health》2013,68(3):381-385
The chemistry of sulfite-bisulfite (the hydrate of sulfur dioxide in mammalian plasma and serum was investigated in vitro and in vivo. The longevity of sulfite in contact with mammalian plasma and known components of blood was determined by adaptation of a colorimetric method for sulfite analysis. Evidence from all experiments indicated that, under physiological conditions, sulfite reacts reversibly with disulfide bonds present in the plasma resulting in formation of S-sulfonates (sulfitolysis). Free sulfite was not detected in plasma of rabbits immediately following exposure to approximately 25 ppm SO2, but there was good evidence for substantial elevation of plasma and serum S-sulfonate content. Reactivity of sulfite with plasma constituents may protect many body tissues from the insult of relatively high concentrations of sulfite and may facilitate prolonged exposure to very low levels of sulfite. 相似文献
2.
The effects of ozone (O3), sulfuric acid (H2SO4), and their interaction on ciliary activity were investigated. Following in vivo exposure to various concentrations of O3 and H2SO4, ciliary activity of isolated tracheal ring cultures was microscopically determined under stroboscopic illumination. Assay of tracheal rings immediately after a 2-hr exposure to 880 μg H2SO4/m3 showed a significant decrease (P < 0.0001) in ciliary beating frequency from controls. Following 72 hr in vitro maintenance, there was still a significant depression (P < 0.01) in ciliary activity of treatment cultures. In vivo recovery studies indicated that ciliary activity had returned to the normal range 72 hr after exposure. Exposure to 196 μg O3/m3 for 3 hr resulted in no significant difference from controls in ciliary activity. Experiments designed to investigate the effects of a sequential exposure to O3 followed by H2SO4 indicated a significant decrease (P < 0.05) in the ciliary beating frequency of exposed animals which was less than that observed with H2SO4 alone. As indicated by the results of these studies, combined action experiments are extremely relevant in assessing the toxicity of environmental pollutants. 相似文献
3.
Hamster tracheal tissue was used to study the effects of H2SO4 mist, carbon particles, and mixtures of the two on cilia beating frequency and morphological alterations of respiratory epithelium. Hamsters were exposed for 3 hr to 1.1 mg/m3 H2SO4 (mean size, 0.12 μm) and 1.5 mg/m3 carbon (mean size, 0.3 μm) particle aerosols alone or in combination. Trachea of animals exposed in vivo to the mixture and held in vivo showed cytotoxic effects in the epithelium that were greater than those produced by either the acid mist or carbon alone. In tracheas of hamsters exposed in vivo and maintained in vitro the damage produced by acid mist—carbon mixture did not differ significantly from that produced by acid mist per se but was greater than that observed after exposure to carbon. Organ cultures of tracheal rings exposed for 3 hr to a 1:106 dilution of concentrated H2SO4 and 100 μg/ml carbon produced epithelial damage in vitro similar to that seen in in vivo exposures. The extent of recovery over a period of 72 hr was also studied following different combinations of in vivo and in vitro exposure and/or maintenance. 相似文献
4.
M. S. Islam E. Vastag Prof. Dr. W. T. Ulmer 《International archives of occupational and environmental health》1972,29(3):221-232
Summary The effect of sulphur-dioxide (SO2) on the bronchial reactivity against acetylcholine (ACH) is carried out on 25 dogs. The dogs were exposed initially to acetylcholine aerosol, then to SO2 for 1 hr and again to ACH. 3 such cycles were repeated. The concentration of SO2 used were 1, 2, 5 and 10 ppm and the controls were given room air in place of SO2.The parameters studied were intrathoracic pressure as the indicator of bronchoconstriction, blood oxygen and carbon-dioxide, tidal volume, respiratory rates and arterial blood pressure. All the SO2 exposed animals have shown a significant increase of bronchial sensitivity than those of the controls. Maximum sensitization was induced by 2 ppm. The reaction provoked by 1 and 5 ppm were almost of the same order and little smaller than 2 ppm but greater than those produced by 10 ppm. The peak reactions against ACH observed for 1, 2 and 5 ppm were 3, 2 and 1 hr of exposure, respectively. After attaining the peak points, the reactions declined in all the 3 groups. But no such trend was obtained for those animals exposed to 10 ppm of SO2.The role of small concentration of SO2 as bronchial sensitizing agent against ACH is discussed.Diese Forschung wurde mit Unterstützung des Vereins zur Untersuchung von Einwirkungen der Luftverschmutzung auf die Volksgesundheit e.V. durchgeführt. 相似文献
5.
Influence of pH on inhibition of bacteria, fungi, and coliphages by bisulfite and sulfite. 总被引:4,自引:0,他引:4
Studies were performed to determine the effects of bisulfite (HSO3?) and sulfite (SO32?), the anionic solubility products of sulfur dioxide (SO2), on the growth of bacteria and fungi and on the survival of a coliphage. Although differential sensitivities to these anions were noted among the test microorganisms, HSO3 was always more inhibitory than SO32?. The inhibitory effects of HSO3? and SO32? were pH dependent: The lower the pH, the greater their toxicity. Consequently, when evaluating the overall effects of pollution by SO2 and the resultant acid rain on the biosphere, attention must be focused on the anionic solubility products of SO2 and on the impact of the pH of the receiver environment on their toxicity to microbes. 相似文献
6.
Estimated 8-hr LC50 values of zinc and cadmium were less than 1 ppm in the absence of soluble calcium and magnesium, but were raised, for example, to 24 ppm of zinc and 19 ppm of cadmium by the addition of calcium plus magnesium at a concentration (500 ppm) equivalent to that of very hard water. Experiments with 65Zn showed that uptake of this element from sublethal concentrations over 8 hr was reduced from approximately 50 × 10?2 μg liter?1 to 10 × 10?2 μg liter?1 per 106 cells by the addition of 500 ppm of calcium and magnesium. Diminished uptake may partly explain the antagonism observed in the toxicity tests. 相似文献
7.
A. A. Landim E. C. Teixeira D. Agudelo-Castañeda I. Schneider Luis F. O. Silva F. Wiegand Prashant Kumar 《Air quality, atmosphere, & health》2018,11(7):801-813
Sulfur dioxide (SO2) is considered the most widespread pollutant that threatens environmental and human health. The purpose of this study is to propose a new method for evaluating the spatial variation of SO2 levels in the Metropolitan Area of Porto Alegre (MAPA). This method included use of Chi-square test to better identify the origin of SO2 sources. Additionally, results of the different methods applied allowed to analyze the temporal SO2 levels and their association with meteorological parameters. SO2 at five sampling sites (Esteio, Canoas, Charqueadas, Triunfo, and Gravataí) were measured during 2010–2015; using fluorescence SO2 automated analyzers. Results showed that Charqueadas had the highest average concentration (~?15 μg m?3), followed by Triunfo (13 μg m?3), Esteio (6 μg m?3), Canoas (3 μg m?3), and Gravataí (2 μg m?3). Chi-square test applied to SO2, and wind direction quadrants showed significant contribution of local emission sources. Seasonal variation revealed higher SO2 levels on cold days for most of the studied sites, except for Esteio site. Day-wise variations revealed higher SO2 concentration on weekdays than weekends for Esteio and Canoas sites, indicating traffic influence especially during the rush-hours. Annual averages analysis identified an increasing trend in SO2 concentrations, implying that applied emission control systems and technological improvement of engines and fuels were not sufficient and thus points out a need for better subsidies mechanisms to pollutant control and effective emission reduction strategies that decision makers, including environmental agencies, must make priority by considering the local realities. 相似文献
8.
Kalina Ranguelova Marcelo G. Bonini Ronald P. Mason 《Environmental health perspectives》2010,118(7):970-975
Background
Sulfur dioxide, formed during the combustion of fossil fuels, is a major air pollutant near large cities. Its two ionized forms in aqueous solution, sulfite and (bi)sulfite, are widely used as preservatives and antioxidants to prevent food and beverage spoilage. (Bi)sulfite can be oxidized by peroxidases to form the very reactive sulfur trioxide anion radical (•SO3−). This free radical further reacts with oxygen to form the peroxymonosulfate anion radical (−O3SOO•) and sulfate anion radical (SO4• −).Objective
To explore the critical role of these radical intermediates in further oxidizing biomolecules, we examined the ability of copper,zinc-superoxide dismutase (Cu,Zn-SOD) to initiate this radical chain reaction, using human serum albumin (HSA) as a model target.Methods
We used electron paramagnetic resonance, optical spectroscopy, oxygen uptake, and immuno-spin trapping to study the protein oxidations driven by sulfite-derived radicals.Results
We found that when Cu,Zn-SOD reacted with (bi)sulfite, •SO3− was produced, with the concomitant reduction of SOD-Cu(II) to SOD-Cu(I). Further, we demonstrated that sulfite oxidation mediated by Cu,Zn-SOD induced the formation of radical-derived 5,5-dimethyl-1-pyrroline N-oxide (DMPO) spin-trapped HSA radicals.Conclusions
The present study suggests that protein oxidative damage resulting from (bi)sulfite oxidation promoted by Cu,Zn-SOD could be involved in oxidative damage and tissue injury in (bi)sulfite-exacerbated allergic reactions. 相似文献9.
Jack D. Hackney William S. Linn Ronald M. Bailey Charles E. Spier Lupe M. Valencia 《Environmental research》1984,34(2):321-327
Young adult asthmatic volunteers (N = 17) were exposed to 0.75 ppm sulfur dioxide (SO2) for 3-hr periods, exercising vigorously for the first 10 min and resting thereafter. Specific airway resistance (SRaw) and symptoms were recorded preexposure, immediately postexercise, and after 1, 2, and 3 hr of exposure. Symptoms and SRaw were significantly increased after exercise, relative to preexposure measurements. Group mean SRaw and symptom increases were no longer significant at 1 hr. In a few individuals, effects may have persisted for 2 hr or more. On separate occasions, comparable exposures were conducted, and forced expiratory spirometry was performed preexposure and postexercise, in addition to the other tests. Inclusion of spirometry did not significantly affect the other results. Spirometry and SRaw showed nearly equal significance in changes postexercise. Thus, in general, asthmatics' bronchoconstriction induced by exercise in SO2 seems to reverse quickly with rest, even if SO2 exposure continues. Spirometry may be useful for studying pollution-induced bronchoconstriction when SRaw measurements are impractical. 相似文献
10.
Mature pollen of Tradescantia paludosa Anders. Sax clone-3 was collected from greenhouse grown plants and desiccated in the dark for 4–5 hours. The pollen was sown on microslides coated with lactose agar medium (supplemented with 0.02% colchicine). Five minutes after sowing, pollen cultures were treated with various concentrations (0.075–2000 ppm) of SO2 obtained from the chemical reaction between K2S2O5 and HCl. Treatments were carried out in an airtight Plexiglas chamber throughout the full incubation period of 19 hours. Treated and control pollen cultures were fixed and stained in aceto-carmine or Feulgen reaction to determine the tube lengths and mitotic indices. Results of repeated experiments indicated that the values of mitotic indices dropped from the normal 38.7% in the control to the range of 24.3-3.8% when treated with 0.075–50.00 ppm of SO2. Pollen tube growth was inhibited from the normal length of 1.5 mm in the control to the range of 800-100 μm when treated with 10–2000 ppm of SO2. The inhibitory effect of SO2 rpresumably resulted from physiological disturbance of the cell and severe damage to chromosomes of both generative and tube nuclei of the pollen tubes. 相似文献
11.
William S. Linn Michael P. Jones Ronald M. Bailey Michael T. Kleinman Charles E. Spier D.Armin Fischer Jack D. Hackney 《Environmental research》1980,22(2):431-438
Normal and asthmatic volunteers (N = 24 and 19, respectively) were exposed to mixed nitrogen dioxide (NO2) and sulfur dioxide (SO2) in purified background air in an environmental chamber under conditions simulating an ambient pollution episode. The NO2 concentration was 0.5 ppm; the SO2 concentration was 0.5 ppm for normals and 0.3 ppm for asthmatics. Exposures lasted 2 hr and included intermittent exercise and heat stress. Control studies consisted of similar exposures to purified air alone. The mixed pollutant gases may have reacted chemically in the exposure chamber, but no appreciable amounts of sulfate or nitrate aerosol were detected there. Group mean lung function changes during exposure generally were not significantly different from control for normals or for asthmatics. Symptoms reported by the normal group showed a small significant overall increase during pollutant exposure and later the same day relative to the corresponding control periods; the asthmatics showed a small significant increase later in the day but not during exposure. The increased symptom reporting showed little consistency from subject to subject: there were small increases for most individual symptom categories evaluated, none of them statistically significant. The results are not sufficient to establish whether this slight and nonspecific clinical response should be attributed to the pollutant mixture or to some other aspect of the exposure protocol. 相似文献
12.
Barrie Tan Regina M. Ruggiero Oliver T. Zajicek Gregory M. Dabkowski 《Archives of environmental contamination and toxicology》1986,15(3):321-326
The anion concentration of the water in the precipitation reservoir and its watershed of Atkins Reservoir, Massachusetts was studied. In the precipitation study, the NO3
– and SO4
2– levels increased with a pH drop andvice versa, but the Cl– was interfered with by regional marine air masses. The average pH of precipitation and the reservoir were 3.85 (SD=±0.89) and 6.08 (SD= ±0.18), respectively. The average alkalinity of the reservoir was very low; 0.88 mg/L CaCO3 (SD= ±0.68). The precipitation and reservoir concentrations of anions were: F– (0.5 and 0.2 ppm), Cl– (2 and 4 ppm), and SO4
2– (7 and 7.8 ppm), respectively. The NO3
– level in the precipitation (4 to 6 ppm) was at least an order higher than the reservoir (0.2 to 0.4 ppm) and this was due to selective NO3
– uptake by terrestrial plants. About 50% of the samples collected at the bottom of the reservoir were high in NO3
– where organic decomposition would be expected. The response of the SO4
2– and and Cl– levels to pH drop in the reservoir inlet study followed a SO4
2– retention-Cl– release mechanism. The F– concentration in the precipitation and reservoir was not dependent on pH changes. The lack of F– in soil samples adjacent to the reservoir indicated that the F– in the reservoir came primarily from precipitation. 相似文献
13.
Experimental human exposure to carbon disulfide 总被引:1,自引:0,他引:1
J. Rosier H. Veulemans R. Masschelein M. Vanhoorne C. Van Peteghem 《International archives of occupational and environmental health》1987,59(3):243-250
Summary Six human volunteers were exposed to 10 and 20 ppm carbon disulfide at rest and to 3 and 10 ppm carbon disulfide under a 50 W level of physical exercise during four consecutive periods of 50 min. At the start of the experiments, at the end of the exposure periods and during the post-exposure period, urine was sampled and the concentration of 2-thiothiazolidine-4-carboxylic acid (TTCA) was determined. It was established that only a small percentage, ranging from 0.7 to 2.2% of the absorbed carbon sulfide was transformed into TTCA. The excretion rate of TTCA (mol TTCA h–1) was found to be the best parameter in evaluating the respiratory uptake of carbon disulfide over a range of 37.9 to 163.3 mg CS2 compared to the urinary concentration of TTCA (mole TTCA ml–1) or the creatinine corrected concentration of TTCA (mmol TTCA mol–1 creatinine). The total amount of TTCA (mol TTCA) excreted proved to be independent of the urinary flow (ml h–1), the estimates of the individual fatty tissue content and the urinary pH. No correlation was found between the respiratory uptake of carbon disulfide (mg CS2) and the excretion rate of TTCA within each exposure condition of 3, 10 or 20 ppm carbon disulfide, respectively. 相似文献
14.
The toxicity of various heavy metals and salts to Eurasian watermilfoil (Myriophyllum spicatum L.) was determined under controlled growth conditions. Toxicants were added to water or to soil in systems with and without woods earth in the substrate.Fifty precent inhibition of root weight occurred with concentrations of 0.25 ppm Cu+2, 1.9 ppm Cr2O7
–2, 3.4 ppm Hg+2, 2.9 ppm AsO2
–1, 7.4 ppm Cd+2, 2.5 ppm Al+3, 9.9 ppm Cr+3, 41.2 ppm Ba+2, 21.6 ppm Zn+2, 13.3 ppm NH4
+1, 22.4 ppm CN–1, 143 ppm B4O7
–2, 363 ppm Pb+2, 10,228 ppm Na2SO4, and 8,183 ppm NaCl. Soil increased toxicity of Cr+2 and Ba+2 but decreased toxicity of Cr2O7
–2, Cu+2, Cd+2, Al+3, and Hg+2. In distilled water, CaCl2 increased toxicity of Cr+3 but not Cr2O7
–2.For most toxicants there was a consistent relationship between inhibition of length and inhibition of weight and between inhibition of roots and inhibition of shoots. However, Cr2O7
–2 disproportionately decreased dry weight, and Hg+2 and Na2SO4 disproportionately decreased stem length growth. With Cd+2 and Cu+2 stem length was greater relative to other measures of growth. Toxicity of Na2SO4 and NaCl was the same when concentrations were calculated as osmotic pressure but not when calculated as Na atoms or as total molecules/L. 相似文献
15.
Mohammad Shohel Hasina Akhter Simol Elizabeth Reid Jeffrey S. Reid Abdus Salam 《Air quality, atmosphere, & health》2017,10(8):981-990
Dew water samples were collected during the winter season (December, 2014 to January, 2015) at an outflow location from the Indo-Gangetic Plain (IGP) to the Bay of Bengal (Coastal Bhola, Bangladesh). Physical properties of the dew water, including pH and electrical conductivity (EC), were measured. The concentrations of water soluble ions (Cl?, SO4 2?, NO3 ?, HCO3 ?, Na+, K+, Ca2+, and Mg2+) and trace metals (Zn, Fe, Mn, Cu, Cr, Pd, and Ni) were also measured. Source characterization of the chemical species was done by correlation analysis, enrichment factor analysis, percent source contribution calculation, and air mass trajectory analysis. The average pH and EC of the collected dew water were 6.81 and 154.80 μS cm?1, respectively. The average concentration of SO4 2? and NO3 ? was 264.10 and 222.20 μeq L?1, respectively. The concentrations of water soluble ions followed the sequence: Ca2+ > Cl?> SO4 2 > Na+ > NO3 ?> Mg2+ > K+ > HCO3 ?. The concentrations of trace metals ranged in order with Zn > Fe > Mn > Cu, while the concentrations of Cr, Pb, and Ni were below detection limit in dew water. Regression analysis showed significant correlations among sea, soil, and anthropogenic species. High enrichment factors of SO4 2?, NO3 ?, Zn, Mn, and Cu indicates anthropogenic sources. Percent source contribution of different species showed significant anthropogenic contribution for Cl?(1.80%), SO4 2?(83.5%), and NO3 ?(99.3%). Air mass trajectory analysis supported that the regional urban pollutions have significant influence on the dew water chemistry at the coastal Bhola, Bangladesh. 相似文献
16.
A total of 43 rainwater samples were collected from March 2014 to February 2015 at a regional atmospheric background station, in Lin’an, Zhejiang province, eastern China. We analyzed all rainwater samples for pH, electrical conductivity, and concentration of SO4 2?, NO3 ?, Cl?, F, NH4 +, Ca2+, Na+, Mg2+, and K+. The pH of the 43 analyzed rainfall events ranged from 3.39–6.37, with a volume-weighted mean (VWM) of 4.74; 72% of the precipitation events qualified as acid rainfall (those where the rain pH was <5.6), indicating that acid rain pollution was severe in Lin’an area. Although the ionic concentrations in the Lin’an rainwater were lower than those found in most urban areas in China and in rural areas in India, they were still higher than those in Waliguan (a global atmospheric background station in northwestern China) and in Newark, NJ, USA. We found that SO4 2? and NO3 ? were the major anions in the precipitation, accounting for an average of 88% of the total inorganic anions. The SO4 2? concentration was between 3.8–303.9 μeq L?1 with a VWM value of 49.8 μeq L?1, while the NO3 ? concentration was between 3.0–206.5 μeq L?1 with a VWM value of 32.6 μeq L?1. The ratios of SO4 2? to NO3 ? ranged from 0.71 to 2.56 with an average of 1.53, indicating that SO4 2? was the most significant anion causing rainfall acidification in Lin’an area. This is similar to observations made in 2008. Compared to observations in Lin’an area in 2008, the contribution of SO4 2? to rainwater acidity had decreased due to sharp reduction in SO2 emissions, while the contribution of NO3 ? had increased due to a rapid growth in the use of motor vehicles in eastern China. We observed that the alkaline component NH4 + made the largest contribution toward neutralizing rainwater acidity. The neutralization factor (NF) for NH4 + was between 0.26 and 1.03 with an average of 0.63, and the NF for Ca2+ was between 0.09 and 1.21 with an average of 0.30. The ratio of Ca2+ to NH4 + was between 0.15 and 4.70 with an average of 0.48, lower than that observed in Chinese urban areas and close to that observed in non-urban Chinese sites. These results indicated that Ca2+ was still a major factor in buffering rainwater acidity in most urban areas in China, while NH4 + seemed to be the most important basic ion for neutralizing rainwater acidity in non-urban areas. In the Lin’an area, the Cl? and K+ in rainwater were mostly of marine origin; however, SO4 2?, Ca2+ and Mg2+ were generated mainly from the earth’s crust and anthropogenic emissions. 相似文献
17.
Empirical equations for explaining trihalomethane (THM) distribution were established based on data on tap water in Osaka City before and after starting the advanced treatment and were represented by the following equations for bromodichloromethane (S1), dibromochloromethane (S2) and bromoform distribution factors (S3) as a function of chloroform distribution factor (S0), respectively: S1 = ?0.97S 0 2 + 0.75S0 + 0.19 (regression coefficient: r = 0.71), S2 = 0.13S 0 2 ?0.76S0 + 0.51 (r = 0.98) and S3 = 0.83S 0 2 ?0.99S0 + 0.30 (r = 0.97). Further, the derived equations were verified by THMs data of Osaka Prefecture and its surrounding cities (except for Osaka City), receiving a combination of advanced treated water and conventionally treated different source water. 相似文献
18.
Marli Maria Knorst Klaus Kienast Herbert Riechelmann Joachim Müller-Quernheim Rudolf Ferlinz 《International archives of occupational and environmental health》1994,65(5):325-328
Summary The effects of 30 min exposure to sulfur dioxide on mucociliary activity (MCA) and ciliary beat frequency (CBF) were studied in 31 guinea pig tracheas. MCA was measured by recording the light reflected from ciliated mucous membranes using an infrared bar code reader. CBF of single ciliated cells obtained by brushing was measured with phase-contrast microscopy. Each tracheal sample was exposed to SO2 at concentrations ranging from 2.5 to 12.5 ppm, or to air for control purposes. MCA and CBF were measured before and immediately after gas exposure. A reduction in mean MCA of 63% (P = 0.0007) and statistically insignificant changes in CBF (P > 0.05) were recorded at concentrations of 2.5 PPM SO2. Higher SO2 concentrations caused a further impairment of MCA as well as a dose-dependent decrease in CBF (P = 0.002). A concentration of 12.5 PPM SO2 induced a decrease from baseline values of approximately 80% in mean MCA and of roughly 70% in mean CBE This study demonstrates a dose-dependent SO2-induced decrease in MCA of guinea pig tracheas. The decrease in MCA was associated with an impairment of CBF only at SO2 concentrations higher than 5.0 ppm. 相似文献
19.
Ralph W. Stacy Ph.D. Dennis House M.S. Mitchell Friedman M.D. Milan Hazucha Ph.D. James Green Ph.D. Louis Raggio B.S. 《Archives of environmental & occupational health》2013,68(4):172-178
Of 31 young, healthy male volunteers who participated in this study, 15 were exposed to air (control) and 16 to 0.75 ppm (2.15 mg/m3) SO2 for 2 hr at 21°C and 60% relative humidity. At the end of the first hour, the subjects exercised for 15 min on a treadmill at 6.4 kmph, with a 10% grade. Methods employed in evaluation of pulmonary function included body plethysmography, spirometry, and multigas rebreathing test. From the battery of 15 pulmonary function parameters, only the pattern of airway resistance changes was significantly altered by SO2 exposure, although spirometric parameters followed a similar pattern. Eight of the SO2-exposed subjects, with one or more positive allergen skin tests, appeared to be significantly more reactive to SO2 than skin test-negative subjects. All subjects remained asymptomatic. The small number of changes observed appeared to be reversible and do not suggest a significant health hazard to normal human subjects exposed to SO2 under these conditions. 相似文献
20.
Median lethal concentration (LC50), LC0, and LC100 values of ethyl acetate for common Indian catfish, Heteropneustes fossilis, were estimated at 24, 48, 72, and 96 hr with 95% confidence limits. The 96-hr LC50 value and harmless (safe) concentration were 212.5 and 63.89 ppm, respectively. Exposure of the fish to 170 ppm of ethyl acetate for 3, 6, 12, 48, and 96 hr induced marked changes in carbohydrate metabolism. Hepatic glycogen values declined significantly at 3, 48, and 96 hr, but there was no marked alteration in muscle glycogen content at any of the exposure periods. Hyperglycemia occurred at all time intervals. Blood pyruvate levels were elevated at 3, 6, 48, and 96 hr. Hyperlacticemia resulted at 3 and 96 hr but hypolacticemia occurred at 6 and 12 hr. Impairment of carbohydrate metabolism might be responsible for the toxic action of ethyl acetate. 相似文献