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1.
William S. Linn Edward L. Avol Deborah A. Shamoo Theodore G. Venet Karen R. Anderson Jill D. Whynot 《Archives of environmental & occupational health》2013,68(4):313-319
Asthmatic volunteers (N = 14) aged 18 to 33 yr with documented sensitivity to sulfur dioxide (SO2) were exposed in a chamber to 0.6 ppm SO2 for 6-hr periods on 2 successive days. Similar exposures to purified air, 1 wk later or earlier, served as controls. Subjects exercised heavily (target ventilation rate 50 L/min) for 5 min near the beginning of exposure (early exercise) and for an additional 5 min beginning after 5-hr of exposure (late exercise). At all other times, they rested. Body plethysmographic measurements and symptom questionnaires were administered pre-exposure, after each exercise period, and hourly during rest. Bronchoconstriction and lower respiratory symptoms were observed during or immediately following exercise—to a slight extent with clean air, and to a more marked extent with SO2. Bronchoconstriction and symptoms were modestly less severe on the second day of SO2 exposure than on the first day, but there were no meaningful differences in response between early and late exercise periods on either day. 相似文献
2.
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
3.
W.S. Linn M.T. Kleinman R.M. Bailey D.A. Medway C.E. Spier J.D. Whynot K.R. Anderson J.D. Hackney 《Environmental research》1981,25(2):404-414
Twenty-one normal volunteers and 19 volunteers with asthma were exposed in an environmental control chamber to a polydisperse aerosol of zinc ammonium sulfate (ZnSO4·(NH4)2SO4)—a model of ambient metallic sulfate aerosols derived from trace metals in fossil fuels—at a nominal concentration of 20 μg/m3. As a model of the background ambient particulate burden, polydisperse sodium chloride aerosol at a nominal concentration of 300 μg/m3 was added to the chamber atmosphere during control as well as exposure studies. Exposure temperature was 20°C and relative humidity was 85%, simulating weather conditions typical of fall/winter ambient pollution episodes. Exposure and control studies were performed on separate days, separated by about 3 weeks, in random order under double-blind conditions. Exposure periods lasted 2 hr and included intermittent light exercise. Lung function and symptoms were evaluated before and at the end of the exposure or control period. Symptom reports showed no significant variation attributable to zinc ammonium sulfate exposure. Group mean lung function measures showed a few significant changes possibly attributable to the sulfate exposure, but these were small and inconsistent. It was concluded that zinc ammonium sulfate produced minimal or no short-term respiratory effects observable under the conditions of the experiment. 相似文献
4.
A Comparison of Changes in Pulmonary Flow Resistance in Healthy Volunteers Acutely Exposed to SO2 by Mouth and by Nose
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On separate occasions, healthy male volunteers were exposed either by nose or by mouth to one of two concentrations of sulphur dioxide, 15 and 28 p.p.m. Exposure to SO2 lasted 10 minutes. Pulmonary flow resistance (R1) was measured by the oesophageal catheter method, and the lung volume was measured by a modification of the gas-compression method; when SO2 was administered by nose, nasal flow resistance (Rn) was measured by means of a catheter placed in the posterior pharynx. The increase in R1 was greater when SO2 was administered by mouth than when it was administered by nose. Similarly, irritative symptoms of the posterior pharynx and chest were more common during exposure by mouth. These findings suggest that the mouth is less effective than the nose as an absorptive surface for SO2. 相似文献
5.
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
6.
S. Wayne Martin DVM MSc Russell A. Willoughby DVM PhD 《Archives of environmental & occupational health》2013,68(3):158-165
Six piglets were continuously exposed to corn dust, corn dust and sulfur dioxide, or corn starch and SO2. There were no clinical or pathological changes in the piglets exposed to corn dust alone. When combined with SO2, both corn dust and com starch produced lesions similar to those observed earlier with SO2 alone. Clinical changes included ocular and nasal irritation with increased salivation and central nervous system depression. Histologically, alterations in the epithelium of the turbinates and trachea included loss of cilia, disappearance of goblet cells, alteration of cell type, and metaplasia. There was a loss of cilia from epithelium of larger bronchi following exposure to corn starch and SO2. There were no changes in the respiratory area of the lung which were attributable to exposure to dust or SO2. 相似文献
7.
Kośmider Stanisław Janiec Waldemar Chruściel Romuald 《International archives of occupational and environmental health》1975,35(1):67-79
Summary Sulfur metabolism was traced in experimental investigations on rats, and the importance of the method for neutralizing sulfur dioxide with ammonia was estimated.The animals were exposed to S35O2 by means of inhalation, and radioactivity in several organs at different periods of exposure was traced.Sulfur incorporation into proteins and mucopolysaccharides, as well as elimination of isotope with urine and feces at different periods of time after exposure, were also determined. The second group of animals was exposed to the products of S35O2 neutralized by ammonia; after performing identical investigations it was found that the use of ammonia to neutralize sulfur dioxide in the air decreased the amount of sulfur which could pass into the organism through the breathing of air contaminated by SO2. The use of S35O2 neutralized by ammonia brings about a faster elimination of sulfur from the organism.This work was supported by the Environmental Protection Agency USA, Project No. 5-533-1. 相似文献
8.
W S Linn D A Fischer D A Shamoo C E Spier L M Valencia U T Anzar J D Hackney 《Environmental research》1985,37(2):445-451
Twenty-four volunteers with chronic obstructive pulmonary disease (COPD) were exposed to sulfur dioxide (SO2) at 0, 0.4, and 0.8 ppm in an environmental control chamber. Exposures lasted 1 hr and included two 15-min exercise periods (mean exercise ventilation rate 18 liter/min). Pulmonary mechanical function was evaluated before exposure, after initial exercise, and at the end of exposure. Blood oxygenation was measured by ear oximetry before exposure and during the second exercise period. Symptoms were recorded throughout exposure periods and for 1 week afterward. No statistically significant changes in physiology or symptoms could be attributed to SO2 exposure. Older adults with COPD seem less reactive to a given concentration of SO2 than heavily exercising young adult asthmatics. This may be due to lower ventilation rates (i.e., lower SO2 dose rates) and/or to lower airway reactivity in the COPD group. 相似文献
9.
William S. Linn Deborah A. Shamoo Theodore G. Venet Charles E. Spier Lupe M. Valencia Ute T. Anzar 《Archives of environmental & occupational health》2013,68(5):278-283
Twenty-eight volunteers with chronic obstructive pulmonary disease were exposed to 0.0, 0.18, and 0.25 ppm ozone in purified air for 1-hr periods with light intermittent exercise, with exposure conditions presented in random order at 1-month intervals. No statistically significant changes attributable to ozone were found in forced expiratory performance or percent oxyhemoglobin (measured near the beginning and end of each exposure). No ozone-related changes in clinical status were found by interviews that included the time for 1 wk before to 1 wk after each exposure, except that a moderate increase in lower respiratory symptoms was reported by nonsmokers in 0.18 ppm exposures only. Thus, a slight decrement in hemoglobin saturation with ozone exposure (reported in two previous studies of chronic obstructive pulmonary disease subjects) may not be a common occurrence under typical ambient exposure conditions. 相似文献
10.
W S Linn D A Shamoo T G Venet C E Spier L M Valencia U T Anzar J D Hackney 《Archives of environmental health》1983,38(5):278-283
Twenty-eight volunteers with chronic obstructive pulmonary disease were exposed to 0.0, 0.18, and 0.25 ppm ozone in purified air for 1-hr periods with light intermittent exercise, with exposure conditions presented in random order at 1-month intervals. No statistically significant changes attributable to ozone were found in forced expiratory performance or percent oxyhemoglobin (measured near the beginning and end of each exposure). No ozone-related changes in clinical status were found by interviews that included the time for 1 wk before to 1 wk after each exposure, except that a moderate increase in lower respiratory symptoms was reported by nonsmokers in 0.18 ppm exposures only. Thus, a slight decrement in hemoglobin saturation with ozone exposure (reported in two previous studies of chronic obstructive pulmonary disease subjects) may not be a common occurrence under typical ambient exposure conditions. 相似文献
11.
Jane Q. Koenig William E. Pierson Martha Horike Robert Frank 《Environmental research》1981,25(2):340-348
Eight adolescent subjects with a diagnosis of extrinsic asthma and exercise-induced bronchospasm were exposed for 30 min at rest followed by 10 min of moderate exercise on a treadmill to the following experimental modes: (a) filtered air, (b) 1 ppm of sulfur dioxide (SO2) and 1 mg/m3 of sodium chloride (NaCl) droplet aerosol, or (c) 1 mg/m3 of NaCl droplet aerosol alone. All exposures were at ?75% relative humidity and 22°C. Functional measurements of total respiratory resistance (RT), maximal flow at 50 and 75% expired vital capacity ( and ), forced expiratory volume in 1 sec (FEV1.0), and functional residual capacity (FRC) were recorded before and after exposure. Statistically significant changes were seen in RT, and , and FEV1.0 following exposure to SO2 NaCl droplet aerosol during exercise. The changes seen were greater than those seen in the same subjects during exposure at rest or in healthy adult subjects exposed to various air pollutants. 相似文献
12.
Glen A. Fairchild DVM Judy Roan James McCarroll MD 《Archives of environmental & occupational health》2013,68(3):174-182
Influenza-infected mice exposed continuously to 20 ppm of sulfur dioxide (SO2) for seven days after virus exposure developed more pneumonia than virus control mice. Dose-response experiments suggested that the post virus SO2-induced increase in influenzal pneumonia began at about 7 to 10 ppm. The increase in pneumonia was not influenced by altering the virus dosage within a 5 to 100 mouse infectious dose range. A similar increase (15% to 20%) in influenzal pneumonia was observed when mice were exposed to 25 ppm of SO2 prior to initiation of virus infection. The SO2 exposure had no effect on the growth of influenza virus in the lungs of mice. Rather, the increase in She amount of pneumonia was associated with SO2 concentrations which induced low-grade, inflammatory lesions in the lung. 相似文献
13.
Jack D. Hackney M.D. Frederick C. Thiede Ph.D. William S. Linn M.A. E. Eugene Pedersen Ph.D. Charles E. Spier David C. Law M.D. 《Archives of environmental & occupational health》2013,68(4):176-181
Adult male volunteers were exposed to nitrogen dioxide (NO2) at 1.0 ppm in purified air under conditions simulating ambient photochemical smog exposures (2-hr exposure with intermittent light exercise at 31°C and 35% relative humidity). Sham exposures to purified air alone served as controls. Exposure effects were assessed by pulmonary physiological tests and by a standardized clinical evaluation. No statistically significant physiological changes attributable to NO2 exposure were found except for a marginal loss in forced vital capacity after exposure on two successive days (1.5%mean decrease p<.05). Reported respiratory and other symptoms were slightly increased with exposure as compared to control, but the change was not significant. Short-term toxicity of NO2 at peak ambient concentrations appears to be substantially less than that of ozone in healthy people, but adverse NO2 effects in diseased people or in long-term exposures cannot be ruled out at present. 相似文献
14.
Robert Z. Maigetter Richard Ehrlich James D. Fenters Donald E. Gardner 《Environmental research》1976,11(3):386-391
Single and multiple 3-hour-long exposures to manganese dioxide (MnO2) aerosol in respirable particle size, altered the resistance to bacterial and viral pneumonias. Increased mortality rates and reduced survival times were observed in mice exposed daily for 3 or 4 days to MnO2 aerosol and challenged with airborne Klebsiella pneumoniae within 1 hour of termination of the last aerosol exposure. When the interval between the exposure and challenge was extended to 5 hours, the altered resistance to infection was seen already after a single 3-hour-long exposure to MnO2 aerosol. Mice infected with airborne influenza virus 24 or 48 hours before initiation of the MnO2 exposures also showed increased mortality rates, reduced survival times, and increased pulmonary lesions. The effect was more pronounced in mice exposed to MnO2 at 48 hours after the infectious challenge. 相似文献
15.
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
16.
Relationship between the airway response to inhaled sulfur dioxide,isocapnic hyperventilation,and histamine in asthmatic subjects 总被引:2,自引:0,他引:2
H. Magnussen R. Jörres H. M. Wagner G. v. Nieding 《International archives of occupational and environmental health》1990,62(7):485-491
Summary To determine whether bronchoconstriction induced by sulfur dioxide can be predicted by the airway response to inhaled histamine, we exposed on two days 46 patients with asthma to air or 0.5 ppm SO2. The exposure protocol consisted of 10 min of tidal breathing followed by 10 min of isocapnic hyperventilation at a rate of 301/min. Airway response was measured before (baseline) and after hyperventilation in terms of specific airway resistance, SRaw. Exposure to air increased baseline mean (SD) SRaw from 6.27 (2.12) to mean (SD) maximum post-hyperventilation SRaw of 9.10 (4.38) cmH2O*s (P < 0.0001). Exposure to SO2 increased mean (SD) baseline SRaw from 6.93 (3.29) to mean (SD) maximum posthyperventilation SRaw of 18.21 (18.69) cmH2O*s (P < 0.0001). Mean (SD) effect of SO2. defined as difference between maximum post-hyperventilation SRaw after SO2 versus air was 9.11 (16.14) cmH2O*s. When evaluated individually, 26 and 34 of the 46 patients showed an airway response to hyperventilation of air and SO2, respectively. Airway response to histamine was determined as the histamine concentration necessary to increase specific airway resistance by 100%, PC100SRaw. The airway response after SO2 and PC100SRaw showed a weak but significant correlation (R = –0.48), whereas the responses to hyperventilation and SO2 did not correlate. We suggest that the mechanisms by which histamine and SO2 exert their bronchomotor effects are different and that in asthmatic patients the risk of pollutant-induced asthmatic symptoms can be poorly predicted by histamine responsiveness.Supported by a grant from the Minister für Jugend, Familie und Gesundheit, Bonn, Federal Repubic of GermanyDedicated to Johannes Piiper on the occasion of the 65th birthday 相似文献
17.
Dose-response study of asthmatic volunteers exposed to nitrogen dioxide during intermittent exercise 总被引:2,自引:0,他引:2
W S Linn D A Shamoo E L Avol J D Whynot K R Anderson T G Venet J D Hackney 《Archives of environmental health》1986,41(5):292-296
Twenty-one mildly asthmatic volunteers were exposed to 0, 0.3, 1.0, and 3.0 ppm nitrogen dioxide (NO2) in purified background air in an environmental control chamber. Exposures were separated by 1-wk periods and occurred in random order. Each lasted 1 hr and included three 10-min bouts of moderately heavy exercise (mean ventilation rate 41 L/min). Exposure temperature was near 22 degrees C and relative humidity near 50%. Specific airway resistance and maximal forced expiratory performance were measured preexposure, after the initial exercise, and near the end of exposure. Bronchial reactivity was assessed immediately following exposure, by normocapnic hyperventilation with subfreezing air. Symptoms were recorded on questionnaires before, during, and for 1-wk after each exposure. Exercise induced significant bronchoconstriction regardless of NO2 level. No statistically significant untoward response to NO2 was observed at any exposure concentration. This negative finding agrees with our previous results, but contrasts with findings elsewhere of respiratory dysfunction after exposure to 0.3 ppm. The discrepancy is presently unexplained, but it may relate to different severity of asthma in different subject groups. 相似文献
18.
J Q Koenig D S Covert M S Smith G van Belle W E Pierson 《Toxicology and industrial health》1988,4(4):521-532
Separate exposures to 0.12 ppm ozone (O3) or 0.18 ppm nitrogen dioxide (NO2) have not demonstrated consistent changes in pulmonary function in adolescent subjects. However, in polluted urban air, O3 and NO2 occur in combination. Therefore, this project was designed to investigate the pulmonary effects of combined O3 and NO2 exposures during intermittent exercise in adolescent subjects. Twelve healthy and twelve well-characterized asthmatic adolescent subjects were exposed randomly to clean air or 0.12 ppm O3 and 0.30 ppm NO2 alone or in combination during 60 minutes of intermittent moderate exercise (32.5 1/min). The inhalation exposures were carried out while the subjects breathed on a rubber mouthpiece with nose clips in place. The following pulmonary functional values were measured before and after exposure: peak flow, total respiratory resistance, maximal flow at 50 and 75 percent of expired vital capacity, forced expiratory volume in one second and forced vital capacity (FVC). Statistical significance of pulmonary function changes was tested by analysis of covariance for repeated measures. After exposure to 0.12 ppm O3 a significant decrease was seen in maximal flow at 50% of FVC in asthmatic subjects. After exposure to 0.30 ppm NO2 a significant decrease was seen in FVC also in the asthmatic subjects. One possible explanation for these changes is the multiple comparison effect. No significant changes in any parameters were seen in the asthmatic subjects after the combined O3-NO2 exposure or in the healthy subjects after any of the exposures. 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.
Oral and Oronasal Breathing During Continuous Exercise Produce Similar Responses to Ozone Inhalation
William C. Adams Ph.D. Edward S. Schelegle Ph.D. James D. Shaffrath M.D. 《Archives of environmental & occupational health》2013,68(5):311-316
Breathing route has a profound effect on sulfur dioxide-induced pulmonary function response in human subjects. There is comparatively little evidence of the effects of oral, nasal, and oronasal breathing on ozone (O3)-induced responses in humans. In this study, six young adult males were exposed on five occasions to 0.40 parts per million (ppm) O3 while exercising continuously at one of two workloads (minute ventilation, [Vdot]E, of ~ 30 and 75 1/min). The [Vdot]E exposure time product was similar for all protocols. Four exposures were delivered randomly with a Hans-Rudolph respiratory valve attached to a silicone facemask, with breathing route effected with and without noseclip. A 2 × 2 analysis of variance revealed no statistically significant differences (p < .05) across conditions in pulmonary function, exercise ventilatory pattern, or subjective symptoms responses. The fifth exposure, delivered via the same respiratory valve with mouthpiece, but without facemask, revealed significantly greater forced expiratory volume in 1 s (FEV1.0) impairment than that observed for the respiratory valve, facemask with noseclip exposure (-20.4% and -15.9%, respectively). The latter suggests partial O3 reactivity to the facemask and clean shaven facial surface of the subjects, although reduced oral scrubbing by mouthpiece-induced bypassing of the oral vestibule might account, in part, for this difference. Recent O3 uptake evidence from another laboratory,15 however, supports our conclusion that breathing route during moderate and heavy continuous exercise does not affect acute physiologic responses to 0.40 ppm O3. 相似文献