Formulation and evaluation of natural antitussive cough syrups.

Among respiratory complications, cough is an important defensive pulmonary reflex that removes fluids, irritants or foreign substances from the respiratory tract. Rosa damascene Mill, petal extract is a traditional medicine and reported to use in the management of cough. In the present study rose petals extract samples were used to prepare natural antitussive cough syrups containing ivy leaf extract to observe synergistic effect of rose water in managing coughing in rats. Four cough formulations (A1, A2, A3 and A4) were prepared. The antitussive activity was observed at three dosage levels; 5ml, 10ml and 15ml. Cough was induced by the standard procedure using sulfur dioxide gas and ammonia. The antitussive activity was recorded by observing the coughing bouts. The result indicated that all formulations had a good effect on cough reduction at 90min but comparing the effect of formulations in all doses formulations, A2 followed by A3 and A4 at 30 minute time interval which is good in comparison with standard Diphenhydramine HCL and Dextromethorphan HBr 10ml in sulfur dioxide gas and ammonia induced cough. Hence, the results of the present study indicated the synergistic effect of rose water in the management of cough ailments.

Inhibitory effects of Enteromorpha linza polysaccharide on micronucleus of Allium sativum root cells.

In this study, the antimutagenic function of the polysaccharide from Enteromorpha linza with the micronucleus test of Allium sativum root cells induced by sulfur dioxide and ultraviolet was studied. The concentration-effect relation of the two inducers was firstly evaluated. The results showed that an increase of genotoxicity damage was demonstrated and micronuclei frequency induced by sulfur dioxide and ultraviolet displayed dose dependent increases. All the doses of polysaccharide did affect the micronuclei frequency formation compared with the negative control. And also, the significant increase in inhibition rate of micronuclei frequency was observed with the increase of the dose of polysaccharide. It was showed maximum inhibition of micronuclei frequency cells (71.74% and 66.70%) at a concentration of 200g/mL in three experiments. The low molecular weight polysaccharide showed higher inhibition rate than raw polysaccharide at the higher concentration (50g/mL) in the absence of sulfur dioxide and ultraviolet. It was confirmed to be a good mutant inhibitor.

The effect of Asian dust on asthma by socioeconomic status using national health insurance claims data in Korea.

CONTEXT: Asian dust events are associated with increased asthma incidence, asthma exacerbation, decreased lung function and increased risk for hospitalization. OBJECTIVE: The purpose of this study was to evaluate the effect of Asian dust events on asthma exacerbation by socioeconomic status using national health insurance claims data. MATERIALS AND METHODS: A case-crossover design was used to analyze asthma-related national health insurance claims, air pollutant and climate data from 2007 to 2013 in Seoul and Incheon, Korea. We stratified our analysis by socioeconomic status (health insurance versus medical aid subscribers) and calculated the maximum air pollutant levels and average climate values per day. The number of asthma-related visits to medical institutions per day was compared between "event" and "control" days. RESULTS: Compared with "control days", the average number of asthma-related visits to medical institutions decreased on "event" days and increased 1-5 d thereafter. The number of visits by health insurance subscribers also decreased on "event" days and increased 1-5 d thereafter, while the number of visits by medical aid subscribers did not change on "event" days but increased 1-4 d thereafter. DISCUSSION AND CONCLUSION: Our study confirms that Asian dust events result in an increased number of asthma-related visits to medical institutions. This effect differed by socioeconomic status.

Antitussive and expectorant activities of Potentilla anserina.

UNLABELLED: Context The root of Potentilla anserina L. (Rosaceae) is an herbal medicine that has been used as an antitussive and expectorant drug for thousands of years in Chinese folk medicine. OBJECTIVE: This study estimated the antitussive and expectorant effects of P. anserina extract to validate its traditional use. Materials and methods The antitussive and expectorant activities of the ethanol extract, aqueous extract, and polysaccharides from P. anserina were evaluated using classical animal models. Results The results showed that in three antitussive tests, the aqueous extract and polysaccharides at high and low doses significantly inhibited the frequency of cough induced by ammonia and sulfur dioxide in mice and by citric acid in guinea pigs, and increased the latent period of cough in guinea pigs. Similarly, the aqueous extract and polysaccharides also showed significant expectorant activity compared with the control in phenol red secretion experiments. Polysaccharides at dose of 600 mg/kg enhanced tracheal phenol red output by 121.1%, the ammonium chloride (positive control) at dose of 1000 mg/kg by 117.4%. However, the ethanol extract at a high dose (600 mg/kg) has antitussive activity only in the sulfur dioxide induced coughing test. Moreover, the polysaccharides at the same dose showed better bioactivity than the aqueous extract in all tests. Discussion and conclusion The results of the present study provide evidence that P. anserina can be used as an antitussive and expectorant herbal medicine and that polysaccharides may be the main active ingredients of P. anserina responsible for its bioactivities.

Effect of nitrogen dioxide and sulfur dioxide on viability and morphology of oak pollen.

BACKGROUND: Nitrogen dioxide (NO2) and sulfur dioxide (SO2) generated by excessive coal combustion and motor vehicle emissions are major air pollutants in the large cities of China. The objective of our study was to determine the effects of the exposure of oak pollens (Quercusmongolica) to several concentrations of NO2 or SO2. METHODS: Pollen grains were exposed to 0.5 ppm to 5.0 ppm NO2 or SO2 for 4 hours and assessed for morphological damage by field emission scanning electron microscopy and for viability using the trypan blue stain. Morphological changes in pollen grains were also examined after contact with acid solutions at pH 4.0 to pH 7.0. RESULTS: Exposure to NO2 or SO2 significantly damaged pollen grains at all concentrations investigated, compared to exposure to air; with exposure to concentrations of 0.5 ppm to 2 ppm resulting in fissures or complete breaks in the exine and a concentration of 5 ppm resulting in complete breakdown and release of pollen cytoplasmic granules. Significantly greater amounts of pollen grain were damaged after exposure to SO2 (15.5-20.4%) than after exposure to NO2 (7.1-14.7%). Similarly, exposure to NO2 or SO2 significantly decreased the viability of pollen grains, compared with exposure to air; with SO2 being slightly more detrimental than NO2. Exposure to acid solutions also induced pollen damage, which appeared to be pH-dependent (from 24.6% at pH 6.0 to 55.8% at pH 4.0; compared to 3.8% at pH 7.0). CONCLUSION: Short-term exposure of oak pollen to high concentrations of SO2 or NO2 significantly increases their fragility and disruption, leading to subsequent release of pollen cytoplasmic granules into the atmosphere. These results suggest that heightened air pollution during the oak pollen season may possibly increase the incidence of allergic airway disease in sensitized individuals by facilitating the bioavailability of airborne pollen allergens.

Fine particulate air pollution and outpatient department visits for headache in Taipei, Taiwan.

This study was undertaken to determine whether there was an association between fine particle matter (PM(2.5)) levels and daily outpatient department visits (OPD) for headaches in Taipei, Taiwan. Daily OPD visits for headaches and ambient air pollution data for Taipei were obtained for the period 2006-2011. The relative risk of visits for OPD headaches was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. For the single-pollutant model (without adjustment for other pollutants), increased OPD visits for headaches were significantly associated with levels of PM(2.5) both on warm days (>23°C) and cool days (<23°C), with an interquartile range rise associated with a 12% (95% CI = 10-14%) and 3% (95% CI = 1-5%) elevation in OPD visits for headaches, respectively. In the two-pollutant models, PM(2.5) remained significant after inclusion of sulfur dioxide (SO2) or ozone (O3) on both warm and cool days. This study provides evidence that higher levels of PM(2.5) increase the risk of OPD visits for headaches in Taipei, Taiwan.

Comparative analyses of physiological responses of Cynodon dactylon accessions from Southwest China to sulfur dioxide toxicity.

Sulfur dioxide (SO2), a major air pollutant in developing countries, is highly toxic to plants. To achieve better air quality and landscape, planting appropriate grass species in severe SO2 polluted areas is very critical. Cynodon dactylon, a widely used warm season turfgrass species, has good SO2-tolerant ability. In this study, we selected 9 out of 38 C. dactylon accessions from Southwest China as representatives of high, intermediate SO2-tolerant and SO2-sensitive accessions to comparatively analyze their physiological differences in leaves under SO2 untreated and treated conditions. Our results revealed that SO2-tolerant C. dactylon accessions showed higher soluble sugar, proline, and chlorophyll a contents under both SO2 treated and untreated conditions; higher chlorophyll b and carotenoid under SO2 treated condition; lower reactive oxygen species (ROS) level, oxidative damages, and superoxide dismutase (SOD) activities under SO2 treated condition; and higher peroxidase (POD) activities under SO2 untreated condition. Further results indicated that SO2-tolerant C. dactylon accessions had higher sulfur contents under both SO2 treated and untreated conditions, consistent with higher SO activities under both SO2 treated and untreated conditions, and higher SiR activities under SO2 treated condition. Taken together, our results indicated that SO2 tolerance of C. dactylon might be largely related to soluble sugar, proline and chlorophyll a contents, and SO enzyme activity.

In vitro exposure of Ostrya carpinifolia and Carpinus betulus pollen to atmospheric levels of CO, O3 and SO 2.

Ostrya spp. and Carpinus spp. pollen was in vitro exposed to three atmospheric pollutants: CO, O3 and SO2. Two levels of each pollutant were used, and the first level corresponds to a concentration about the atmospheric hour-limit value acceptable for human health protection in Europe and the second level to about the triple of the first level. Experiments were done under artificial solar light with temperature and relative humidity controlled. The viability of the exposed pollen samples showed a significant decrease. Also, the germination percentage showed a significant decrease in both exposed pollens, and the effect was most pronounced for SO2, followed by O3 and CO. A general decreasing trend in the total soluble protein content of the exposed pollen samples when compared with the control was observed, but it was only statistically significant for the Ostrya spp pollen. The results showed marked effects were observed on the Ostrya spp. and Carpinus spp. pollen when exposed to air pollutant levels that can be considered safe for human health protection.

Physiological responses of the tropical tree Tibouchina pulchra Cogn under the influence of combustion of crude oil and natural gas at an oil refinery.

A refinery located on the slopes of a mountain range in the city of Cubatão (SE-Brazil) is the main source of sulfur dioxide (SO(2)) in the region. For this reason, the refinery replaced a system in which energy was produced from crude oil combustion in boilers with a system of energy and vapor co-generation in a thermoelectric power plant fueled by natural gas. The aim of this study was to investigate the responses of Tibouchina pulchra to the fuel switching. Saplings planted in pots were distributed throughout monitoring sites around the polluting source (sites I, II, III and IV) and in a site (V) far from emissions. Changes on the plants responses occur along the three fuel switching phases. During the last phase, increased carbon assimilation (Asat) and decreased stomatal conductance (gs) were observed in plants growing in sites II and III; as a consequence, intrinsic water use efficiency (iWUE) increased. However, the increase in Asat did not promote growth increase suggesting that changes at the refinery did not result in better air quality, but only in a change in the main contaminants.

Air quality biomonitoring through pollen viability of Fabaceae.

In this study, pollen viability and germination of three plant species, Cercis siliquastrum L., Robinia pseudoacacia L., and Spartium junceum L., belonging to the Fabaceae family, was evaluated in sites with different intensity of road traffic, constantly monitored with continuous analysers for air pollutants (carbon monoxide (CO), sulphur dioxide (SO(2)), and nitrogen dioxide (NO(2))) by the Municipality of Catania. Two sites, in which road traffic was absent, were selected, too. The percentages of viable pollen by 2,3,5-trypheniltetrazolium chloride (TTC) test ranged from 59.0 to 90.2 % in C. siliquastrum, from 61.5 to 83.5 % in S. junceum and from 67.5 to 84.3 % in R. pseudoacacia. The percentages of germination varied from 41.0 to 72.7 % in C. siliquastrum, from 42.0 to 64.7 % in S. junceum and from 38.3 to 66.3 % in R. pseudoacacia. The highest percentages of viable pollens were found in no-road traffic stations by either TTC or germination tests, while the lowest values were detected in a site characterised by heavy road traffic. In the monitored period (2007-2009), pollen viability, germinability and tube length of C. siliquastrum resulted in a significant negative correlation to CO, SO(2) and NO(2), whereas data from TTC and germination tests on S. junceum and R. pseudoacacia pollens were not well correlated to air pollutants. The results showed that pollen viability, germination and tube growth in C. siliquastrum were affected by air pollution. S. junceum and R. pseudoacacia were not very influenced by air pollutants, suggesting a different pollen sensitivity of these species.

Sulfur fumigation, a better or worse choice in preservation of Traditional Chinese Medicine?

Sulfur fumigation (SF) in Traditional Chinese Medicine (TCM) is a highly efficient and important traditional preservation method in China. This method has generated a great deal of concern and has been disputed in the last few years because of its uncertain safety. SF can alter the quality of TCMs by damaging the bioactive compounds, changing chemical profiles, and generating detrimental exogenous materials. However, SF is still widely used in the herbal medicinal industry because of its various benefits, such as its pesticidal and anti-bacterial effects, easy operation, and low-cost. This review contains the current situation, chemical mechanism and reactions during SF, the pharmacological and pharmacokinetic research, and the influence of quality caused by SF. In addition, a quantification-operation sulfur fumigation device (QOSFD), which can maintain the quality of TCMs by controlling the SF processing parameters, has been designed and introduced. The key technologies of this device involve controlling the O(2) content and the temperature of SO(2) as well as the quantification of sulfur in SF. This device can reduce the possibility of reaction between bioactive compounds and sulfur/sulfurous acid, as well as control the limitation of SO(2) residues. The QOSFD is regarded as a promising preservation technique in the field of TCM, medicinal materials, agriculture, and fruit industry.

In vitro exposure of Acer negundo pollen to atmospheric levels of SO2 and NO2: effects on allergenicity and germination.

In the last years, a rising trend of pollen allergies in urban areas has been attributed to atmospheric pollution. In this work, we investigated the effects of SO(2) and NO(2) on the protein content, allergenicity, and germination rate of Acer negundo pollen. A novel environmental chamber was assembled to exposure pollen samples with SO(2) or NO(2) at two different levels: just below and two times the atmospheric hour-limit value acceptable for human health protection in Europe. Results showed that protein content was lower in SO(2)-exposed pollen samples and slightly higher in NO(2)-exposed pollen compared to the control sample. No different polypeptide profiles were revealed by SDS-PAGE between exposed and nonexposed pollen, but the immunodetection assays indicated higher IgE recognition by all sera of sensitized patients to Acer negundo pollen extracts in all exposed samples in comparison to the nonexposed samples. A decrease in the germination rate of exposed in contrast to nonexposed pollen was verified, which was more pronounced for NO(2)-exposed samples. Our results indicated that in urban areas, concentrations of SO(2) and NO(2) below the limits established for human protection can indirectly aggravate pollen allergy on predisposed individuals and affect plant reproduction.

Effects of several environmental factors on longevity and health of the human population of Zhongxiang, Hubei, China.

Increasing human health and longevity is of global interest. Environmental, genetic, and stochastic factors all affect longevity. Among these factors, the environment is extremely important. To investigate the relationship between the environment and longevity, we studied the environment in Zhongxiang (China), where the inhabitants commonly have long life spans. Air was analyzed for negative oxygen ions, SO2, and inhalable particles, while drinking water and rice were analyzed for macro- and micro-elements. The air quality in this area was determined to be grade I with high negative oxygen ion content and low SO2 and inhalable particle contents. Apart from Fe, Mn, and F, all tested elements and the pH were within national standards and World Health Organization guidelines. The percentage of long-lived people in the area was closely related to the macro- and micro-element contents of their staple food, rice. The elements in rice could be classified into three categories according to their effect on longevity: Sr, Ca, Al, Mo, and Se, which were positively correlated with longevity; Fe, Mn, Zn, Cr, P, Mg, and K, which had a weak effect on local longevity, and Cu and Ba, which had a negative effect on longevity.

Simulation and assessment of SO2 toxic environment after ignition of uncontrolled sour gas flow of well blowout in hills.

To study the sulfur dioxide (SO(2)) toxic environment after the ignition of uncontrolled sour gas flow of well blowout, we propose an integrated model to simulate the accident scenario and assess the consequences of SO(2) poisoning. The accident simulation is carried out based on computational fluid dynamics (CFD), which is composed of well blowout dynamics, combustion of sour gas, and products dispersion. Furthermore, detailed complex terrains are built and boundary layer flows are simulated according to Pasquill stability classes. Then based on the estimated exposure dose derived from the toxic dose-response relationship, quantitative assessment is carried out by using equivalent emergency response planning guideline (ERPG) concentration. In this case study, the contaminated areas are graded into three levels, and the areas, maximal influence distances, and main trajectories are predicted. We show that wind drives the contamination and its distribution to spread downwind, and terrains change the distribution shape through spatial aggregation and obstacles. As a result, the most dangerous regions are the downwind areas, the foot of the slopes, and depression areas such as valleys. These cause unfavorable influences on emergency response for accident control and public evacuation. In addition, the effectiveness of controlling the number of deaths by employing ignition is verified in theory. Based on the assessment results, we propose some suggestions for risk assessment, emergency response and accident decision making.

Potential genotoxic effects of melted snow from an urban area revealed by the Allium cepa test.

The presence of well-known atmospheric pollutants is regularly screened for in large towns but knowledge about the effects of mixtures of different pollutants and especially their genotoxic potential is largely missing. Since falling snow collects pollutants from the air, melted snow samples could be suitable for evaluating potential genotoxicity. For this purpose the Allium cepa anaphase-telophase test was used to analyse melted snow samples from Belgrade, the capital city of Serbia. Samples of snow were taken at two sites, characterized by differences in pollution intensity, in three successive years. At the more polluted site the analyses showed a very high degree of both toxicity and genotoxicity in the first year of the study corresponding to the effects of the known mutagen used as the positive control. At the other site the situation was much better but not without warning signals. The results showed that standard analyses for the presence of certain contaminants in the air do not give an accurate picture of the possible consequences of urban air pollution because the genotoxic potential remains hidden. The A. cepa test has been demonstrated to be very convenient for evaluation of air pollution through analyses of melted snow samples.

Western Canada study of animal health effects associated with exposure to emissions from oil and natural gas field facilities. Study design and data collection III. Methods of assessing animal exposure to contaminants from the oil and gas industry.

Researchers measured exposure to oil and gas industry emissions in 205 cow-calf herds located in Western Canada. They measured airborne concentrations of sulfur dioxide, hydrogen sulfide, and volatile organic compounds with passive monitors placed in each pasture, wintering, or calving area that contained study animals from the start of the breeding season in the spring of 2001 until June 30, 2002. Researchers continued air monitoring in a subset of herds to the end of the study in fall 2002. Each sampling device was exposed for 1 month and then shipped to the laboratory for analysis. New samplers were installed and the shelters relocated, as necessary, to follow the movements of herd-management groups between pastures. Researchers linked the results of the air-monitoring analysis to individual animals for the relevant month. For the 205 herds examined at pregnancy testing in 2001, monthly mean exposures on the basis of all available data were as follows: sulfur dioxide, geometric mean (GM)=0.5 ppb, geometric standard deviation (GSD)=2.2; hydrogen sulfide, GM=0.14 ppb, GSD=2.3; benzene, GM=0.247 microg/m3, GSD=2.5; and toluene, GM=0.236 microg/m3, GSD=2.7. Benzene and toluene were surrogates for volatile organic compound exposure. In addition to passive measurements of air quality, researchers obtained data from provincial regulatory agencies on the density of oil and gas field facilities and on flaring and venting from the surrounding facilities. They developed the data into additional measures of exposure that were linked to each animal at each location for each month of the study.

The association between exposure to the oil and gas industry and beef calf mortality in Western Canada.

Researchers assessed the association between exposure to emissions from oil and gas field facilities and newborn calf survival and health status by determining the risks of calf mortality and treatment reported for 27,511 beef calves born to cows in 203 herds, which were followed from the beginning of the 2001 breeding season through the 2002 calving season. They prospectively measured exposures to sulfur dioxide, hydrogen sulfide, and volatile organic compounds (VOCs) by using data from passive air monitors. They also used the density of oil and gas well sites surrounding each pasture as an additional measure of exposure. The researchers found that well-site density as well as exposures to hydrogen sulfide and VOCs measured as benzene or toluene were not associated with the odds of calf mortality in the first 3 months of life. After adjusting for cow-and herd-level risk factors, they found that exposure to sulfur dioxide near the time of calving was associated with an increased risk of calf mortality during this period. Exposure to sulfur dioxide in the 3-month period before calving was most suggestive of a causal exposure-response relationship (the odds ratio for every 1 ppb increase in sulfur dioxide=1.32; 95% confidence interval=1.13-1.54; p=0004). Exposure to sulfur dioxide, hydrogen sulfide, and VOCs measured as benzene or toluene during gestation was not associated with the odds of calf treatment in the first 3 months of life. However, exposure to sulfur dioxide, hydrogen sulfide, and VOCs measured as benzene or toluene, and sulfur dioxide in the first month after calving, was associated with a small increase in the odds of calf treatment after the first month of life when risk was compared across quartiles for exposure; only the association between hydrogen sulfide exposure and the odds of treatment was consistent with a causal exposure.

Risk of nonpregnancy, risk of disposal for pregnant cows, and duration of the calving interval in cow-calf herds exposed to the oil and gas industry in Western Canada.

To determine potential associations between emissions from oil and gas field facilities and the reproductive success of cow-calf herds in Western Canada, researchers followed approximately 33,000 beef cows from the beginning of the breeding season in 2001 through pregnancy testing in 2002. They prospectively measured exposure to sulfur dioxide, hydrogen sulfide, and volatile organic compounds (VOCs) by using data from passive air monitors installed in pastures and linked to the locations of individual animals. They used the density of oil and gas well sites surrounding each pasture as an additional measure of exposure. The researchers measured the risk of nonpregnancy in cattle in 205 herds in fall 2001 and 200 herds in fall 2002, and they determined the interval between the dates of calving in 2001 and 2002 for all cows calving in both years from 202 herds. The risk of disposal in pregnant cows was measured as the risk of removal from inventory for any reason other than nonpregnancy between pregnancy testing in 2001 and calving in 2002. There was no evidence that exposure to sulfur dioxide or VOCs measured as benzene and toluene increased the odds of nonpregnancy or disposal for pregnant cows. Density of oil and gas well sites was not related to the odds of nonpregnancy in either 2001 or 2002 or the odds of disposal for pregnant cows. During the first month after bull contact, exposures to increasing concentrations of sulfur dioxide, VOCs measured as toluene, and the density of oil and gas well sites were also not associated with an increase in the 2001-2002 breeding-to-calving interval. However, there was an estimated 3.0-day increase in the breeding-to-calving interval for mature cows exposed to benzene concentrations in the highest quartile of exposure (>0.236 microg/m3) compared with those cows exposed to benzene concentrations in the lowest quartile of exposure (<0.082 microg/m3).

Ophiopogon root (Radix Ophiopogonis) prevents ultra-structural damage by SO2 in an epithelial injury model for studies of mucociliary transport.

We studied the action of the herb, Ophiopogon root (OR) in a epithelial injury model, hypothesizing that it may have beneficial effects on mucociliary transport following injury to the palate induced by sodium metabisulphite (MB) which releases SO(2) on contact with water. OR (extract from 1g of root/ml)-incubated palates and non-incubated palates were compared to assess the effect of MB on mucociliary clearance on the bull frog palate. MB 10(-1) M, acutely increased mucociliary clearance time (MCT) by 254.5 +/- 57.3% in untreated and 243.3 +/- 98.5% in OR-incubated palates, (over all significance assessed by one-way ANOVA, F = 12.82, p < 0.001, df = 8,54 for MB and F = 10.56, p < 0.001, df = 8,54 for OR). MCT returned to normal during recovery in OR-treated palates following MB. In untreated palates, MCT did not return to control values during a similar recovery period. ANOVA comparing MCTs in the recovery period in untreated vs OR-treated palates was significantly different (F = 2.92, p < 0.03, df = 5,36). SEM images of epithelial tissue, analyzed by morphometry, showed a 25 +/- 12% loss of ciliated cells in untreated palates and little or no damage to cilia in OR-treated palates. Intact groups of ciliated cells were found in SEM micrographs of mucus from MB-treated palates. We conclude that the loss of cilia or ciliated cells prevented full recovery of MCT after MB in untreated palates. In OR-incubated palates, mucociliary transport was completely restored within 20 min after topical application of MB, possibly through a protective action on the extra-cellular matrix.

Effect of sulfur dioxide inhalation on the glutathione redox system in mice and protective role of sea buckthorn seed oil.

This study investigated the effects of sulfur dioxide (SO2) inhalation and protection by sea buckthorn seed oil from oxidative damage caused by SO2 in male Kunming-strain mice. One approach was set up to study the effects of SO2 inhalation on changes of the mice antioxidant defense system. SO2 at different concentrations (22 +/- 2, 64 +/- 3, and 148 +/- 23 mg/m3) was administered to animals in treatment groups for 7 days, 6 h per day, while control groups were exposed to filtered air under the same condition. The activities of glutathione-S-transferase (GST) and glucose-6-phosphate dehydrogenase (G6PD) and the contents of reduced glutathione (GSH) in brain, lung, heart, liver, and kidney of mice were measured. In the case of inhalation of a SO2 concentration of 148 +/- 23 mg/m3, the activities of GST and G6PD and contents of GSH in the brain, lung, heart, liver, and kidney were significantly decreased. Dose-dependent relations were found between various SO2-exposed concentrations and the activities of GST and G6PD and the content of GSH. Meanwhile another approach was taken to determine whether sea buckthorn seed oil could maintain the glutathione redox system and prevent the oxidative damage of lung induced by SO2. In groups given a high dosage (6 or 8 ml/kg) intraperitoneally, the level of TBARS (thiobarbituric acid-reactive substances) was decreased significantly (p < 0.05) by the injection of sea buckthorn seed oil, and the activity of GST was increased significantly (p < 0.05). Overall GST activity and TBARS level exhibited a significant negative correlation (r = 0.891, p < 0.05). The observations showed that SO2 inhalation resulted in a significant change in the glutathione redox system and indicated that sea buckthorn seed oil could contribute to the antioxidant effects in the case of SO2 exposure.