Long-Term Exposure to Sulfur Dioxide,Sulfuric Acid Mist,Fly Ash,and Their Mixtures

Groups of cynomolgus monkeys and guinea pigs were exposed to mixtures of sulfur dioxide, fly ash, and sulfuric acid mist. The exposure concentrations varied between 0.1 and 5.0 ppm for sulfur dioxide, 0.1 and 1 mg/cu m for sulfuric acid mist, while a concentration of approximately 0.5 mg/cu m was used for fly ash. The duration of exposure was 52 weeks for guinea-pigs and 78 weeks for monkeys.

Pulmonary function tests and serum biochemical and hematological analyses were conducted prior to and periodically during the exposure period. At the termination of exposure, the lungs were examined microscopically. Analysis of the data revealed that in groups exposed to the mixtures of pollutants, sulfuric acid mist was responsible for the effects observed. No synergistic action between the pollutants was detected.     

Long-Term Nitrogen Dioxide Exposure

Male Long Evans hooded rats were chronically exposed to an average 2.9 ppm (±0.71 SD) of nitrogen dioxide 24 hours each day, five days a week for nine months. The major effects of NO₂ were a significant 12.7% increase in lung wet weight, a 13.0% decrease in lung compliance, and a significant reduction in surface-active properties of the lung wash. The NO₂-exposed lungs also revealed a significant 8.7% decrease in lung lipid content and a marked decrease in percentage of total saturated phospholipid fatty acids. This reduction in saturation was due almost entirely to a decrease in the percentage of palmitic acid. The suggestion is made that alterations in lung lipid metabolism may be the underlying mechanism which leads to some of the pulmonary effects following long-term exposure to subacute levels of NO₂.     

Mouse Lung Structure and Function after Long-Term Exposure to an Atmospheric Carbon Dioxide Level Predicted by Climate Change Modeling

Background: Climate change models predict that atmospheric carbon dioxide [CO2] levels will be between 700 and 900 ppm within the next 80 y. Despite this, the direct physiological effects of exposure to slightly elevated atmospheric CO2 (as compared with ∼410 ppm experienced today), especially when exposures extend from preconception to adulthood, have not been thoroughly studied.Objectives: In this study we aimed to assess the respiratory structure and function effects of long-term exposure to 890 ppm CO2 from preconception to adulthood using a mouse model.Methods: We exposed mice to CO2 (∼890 ppm) from prepregnancy, through the in utero and early life periods, until 3 months of age, at which point we assessed respiratory function using the forced oscillation technique, and lung structure.Results: CO2 exposure resulted in a range of respiratory impairments, particularly in female mice, including higher tissue elastance, longer chord length, and lower lung compliance. Importantly, we also assessed the lung function of the dams that gave birth to our experimental subjects. Even though these mice had been exposed to the same level of increased CO2 for a similar amount of time (∼8wk), we measured no impairments in lung function. This suggests that the early life period, when lungs are undergoing rapid growth and development, is particularly sensitive to CO2.Discussion: To the best of our knowledge, this study, for the first time, shows that long-term exposure to environmentally relevant levels of CO2 can impact respiratory function in the mouse. https://doi.org/10.1289/EHP7305     

Chronic Exposure to Coal Fly Ash Causes Minimal Changes in Corticosterone and Testosterone Concentrations in Male Southern Toads Bufo terrestris

More than 50% of the electricity in the United States is produced by coal-burning power plants. The byproduct of coal-burning plants is coal fly ash, which contains increased concentrations of trace metals and is disposed of in collection basins. Southern toads (Bufo terrestris) frequently use these basins for reproduction. Male toads were collected in spring 2001 and 2002 from an ash basin and a reference site and divided into four groups: toads collected at the control site and maintained on (1) control substrate and food or (2) ash and contaminated food and toads collected at the ash site and maintained in (3) control or (4) ash conditions. Blood was collected periodically during 5 months to determine testosterone and corticosterone concentrations. Reference to ash toads exhibited a significant, transient increase in corticosterone at 4 weeks, but neither corticosterone nor testosterone continued to increase beyond this time. In contrast, toads caught and maintained on ash did not exhibit increased corticosterone. Testosterone in these toads appeared to be unrelated to ash exposure. This unexpected lack of a corticosterone response and no effect on testosterone suggests that toads chronically exposed to trace metals can acclimate to a polluted environment, but they may still experience subtle long-term consequences.     

二氧化硫和二氧化氮混合气体对豚鼠气道反应的作用

目的 探讨二氧化硫（SO2）和二氧化氮（NO2）混合气体对豚鼠气道反应的影响。方法 40只成扯豚鼠平均分为4组吸入不同浓度SO2和NO2混合气体（A组：SO214.3mg /m^3 NO23.1mg/m^3 空气;B组：SO228.6mg/m^3 NO26.1mg/m^3 空气;C组：SO242.9mg/m ^3 NO210.3mg/m^3 空气;对照组吸入空气）,分别于0、5、1、15min测定气道内压（IP）,另外用组织胺进行气道反应激发试验。结果 吸入三组不同浓度SO2和NO2混合气体5minIP升高,15min时,A、B组下降,差异均无显著性（P＞0.05）,组胺激发后三组PC20值与对照组相比差异显著（P＜0.05）。结论 短时吸入混合SO2和NO2气体可使豚鼠气道反应性增高。     

Metal Accumulation and Health Effects in Raccoons (Procyon lotor) Associated with Coal Fly Ash Exposure

Approximately 5.4 million cubic yards of coal fly ash and water spilled into the Emory River embayment of Watts Bar Reservoir in east Tennessee on Dec 22, 2008. Raccoons were collected in 2009 and 2010 from the spill site (10/y) and unexposed areas (5/y) to determine whether metals and metalloids were accumulating in raccoons and if any negative health effects resulted from exposure to the spilled coal fly ash. Tissues were analyzed from each animal to determine the concentrations of 26 metals/metalloids. Complete blood cell counts (CBC), plasma biochemistry panels, and histopathology of select tissues also were performed. Results were analyzed by year and exposure status. Although significant differences were present in some tissues for some metals/metalloids, only arsenic in hair, iron in muscle, nickel in hair, selenium in hair and muscle, strontium in hair, and vanadium in hair and liver were increased in spill site animals (one or both years) compared with unexposed animals. No clinically important differences were observed between groups regarding CBC or plasma biochemistry analyses. Lesions were observed on histopathology in some tissues, but there was no difference in the prevalence of lesions between spill site and unexposed animals. There does not seem to be any important accumulation of metals/metalloids or negative health effects in raccoons associated with exposure to coal fly ash compared with unexposed animals.     

不同浓度SO_2吸入染毒诱导运动大鼠心肺组织的氧化损伤效应

目的 研究不同浓度SO_2吸入染毒对运动大鼠心肺组织超氧化物歧化酶(SOD)活力、还原型谷胱甘肽(GSH)及丙二醛(MDA)含量的影响,探讨SO_2污染对运动者心肺组织损伤的机制.方法 48只SD雄性大鼠随机分为8组:空白对照组、单纯运动组、低污染运动组、低污染安静组、中污染运动组、中污染安静组、高污染运动组和高污染安静组.除了空白对照组和单纯运动组,其余各组均置于不同浓度SO_2污染环境中(低、中、高污染组SO_2浓度分别为5、10、15mg/m~3),运动组大鼠进行跑轮运动(8 m/min,2 h/d,共10 d).24 h后处死大鼠,取心肺组织匀浆后立即进行抗氧化酶和脂质过氧化水平测定.结果 肺组织SOD活力在高污染运动组、高污染安静组、中污染运动组、中污染安静组、低污染运动组较空白对照组显著降低(P＜0.05);心组织SOD活力却出现单纯运动组、中污染安静组升高而高污染安静组、高污染运动组下降的变化趋势(P＜0.05).心肺组织的GSH含量中污染安静组升高而高污染运动组、高污染安静组、中污染运动组下降(P＜0.05).MDA水平各实验组较安静对照组显著升高(P＜0.05).同一浓度污染环境中运动组与安静组相比,SOD活力、GSH含量显著降低,MDA水平显著升高(P＜0.05),且存在剂量-效应关系.结论 SO_2污染可引起大鼠心肺组织的氧化损伤,而SO_2污染对运动大鼠心肺组织的氧化损伤效应比安静组更明显.

Abstract：

Objective To investigate the effects of sulfur dioxide(SO_2)pollution in difierent concentrations on activity of SOD,levels of GSH and MDA in heart and lung tissue of exercised rats,in order to elucidate the toxicological mechanism of SO_2 pollution.Methods Forty-eight SD rats were randomly divided into eight groups:a rest group(RG),an exercise group(EG),a low pollution exercise group (LEG),a low pollution rest group(LRG),a moderate pollution exercise group(MEG),a moderate pollution rest group(MRG),a high pollution exercise group(HEG)and a high pollution rest group(HRG).All groups,except RG and EG,were exposed to SO_2 with difierent concentrations(5 mg/m~3,10 mg/m~3,15 mg/m~3),meanwhile exercised rats run in a motor-driven wheel at a speed of 8 m/min,2 h/d for 10 days.Rats were sacrificed at 24 h after treatment and the anti-oxidative enzymes activity and lipid peroxidation(LPO)levels were measured.Results Compared with RG,SOD activity of lung tissue significantly decreased in HEG,MEG,LEG(P＜0.05),whereas the change of SOD activity of heart showed a tendency that EG,MRG raised and HRG,HEG declined(P＜0.05).GSH levels of heart and lung tissue appeared a conspicuous increase in MRG and a noticeable decrease in HEG,HRG,MEG(P＜0.05).MDA levels of heart and lung tissue in each group had a significant increase in comparison with RG(P＜0.05).Compared with the rest group in the same polluted environment,SOD activity and GSH levels of heart and lung tissue in exercise groups had a markedly decrease while MDA levels significantly increased(P＜0.05),with a dose-dependent manner.Conclusion SO_2 exposure can induce oxidative damage in exercised rats' heart and lung tissue,which is more significant than rest rats.     

Thyroid Function of Newborns and Exposure to Chlorine Dioxide By-products

In this study, the authors compared thyroid function of newborns from 11 municipalities where drinking water was disinfected by chlorine dioxide (ClO₂) with that of newborns from 15 municipalities using chlorine disinfection. They estimated the mean neonatal blood thyroid stimulating hormone (TSH) levels and proportion of congenital hypothyroidism cases using the results of the Québec neonatal screening for congenital hypothyroidism for 32,978 newborns over the period 1993–1999. There was no significant increase in the TSH level and no excess of congenital hypothyroidism when all newborns exposed to ClO₂ were considered. However, for newborns with low birth weight, mean TSH level was significantly higher among those exposed to ClO₂ than for those in the reference group.     

Time and Causation in Studies of Long-Term Exposure to Environmental Factors

The various shortcomings of the prevalence study as an instrument for causal research are evaluated by comparing the prevalence design with the classical experimental design. On the basis of these shortcomings it is suggested that epidemiologists refine their research strategies in two respects, both related to time. (1) it is suggested that they include formerly exposed as well as presently exposed in their sampling frames and (2) that they avoid using present status with respect to causal factors as indicators of life-experience of these factors in analysis.

On the basis of some studies of the relationship between long-term exposure to presumed noxae and chronic Sung disease, numerical examples of the undesirable consequences of ignoring time are given.     

两类噪声作业工人个体噪声暴露特点的观察

[目的]观察和比较接触稳态噪声和非稳态噪声工人个体之间、工作日之间个体噪声暴露的特点和规律。[方法]应用噪声个体计量仪分别测量了4名细纱车间挡车工(稳态噪声)和4名机械加工车间工人(非稳态噪声)3个工作日(班次)的个体噪声暴露,用工作期间的8h等效声级(LAeq.8h)作为评价指标。[结果]两组工人个体噪声暴露的时间图显示其工作环境噪声性质分别为典型的稳态噪声和非稳态噪声。稳态噪声组12人次个体噪声暴露的LAeq.8h最大、最小值和差值分别为99.2、92.8和6.4dB(A);非稳态噪声组相应数值为89.9、83.1和6.8dB(A)。稳态噪声组每名工人3个班次个体噪声暴露均数的最大值和最小值为(98.0±1.1)、(94.3±1.5)dB(A),非稳态噪声组为(87.9±1.0)、(85.1±1.5)dB(A)。稳态噪声组4名工人每个班次个体噪声暴露均数的最大值和最小值为(96.6±1.9)、(95.8±2.0)dB(A),非稳态噪声组为(87.1±3.0)、(86.1±2.1)dB(A)。[结论]在接触稳态噪声和非稳态噪声的两组人群中,1名工人1次或多次个体噪声暴露测量结果不能准确评估该工人所在人群的噪声暴露水平,多名工人1次个体噪声暴露测量的平均值可以作为评估该组工人所在人群的噪声暴露水平的依据。     

Maternal Exposure to Nitrogen Dioxide during Pregnancy and Offspring Birth Weight: Comparison of Two Exposure Models

Background

Studies of the effects of air pollutants on birth weight often assess exposure with networks of permanent air quality monitoring stations (AQMSs), which have a poor spatial resolution.

Objective

We aimed to compare the exposure model based on the nearest AQMS and a temporally adjusted geostatistical (TAG) model with a finer spatial resolution, for use in pregnancy studies.

Methods

The AQMS and TAG exposure models were implemented in two areas surrounding medium-size cities in which 776 pregnant women were followed as part of the EDEN mother–child cohort. The exposure models were compared in terms of estimated nitrogen dioxide (NO₂) levels and of their association with birth weight.

Results

The correlations between the two estimates of exposure during the first trimester of pregnancy were r = 0.67, 0.70, and 0.83 for women living within 5, 2, and 1 km of an AQMS, respectively. Exposure patterns displayed greater spatial than temporal variations. Exposure during the first trimester of pregnancy was most strongly associated with birth weight for women living < 2 km away from an AQMS: a 10-μg/m³ increase in NO₂ exposure was associated with an adjusted difference in birth weight of −37 g [95% confidence interval (CI), −75 to 1 g] for the nearest-AQMS model and of −51 g (95% CI, −128 to 26 g) for the TAG model. The association was less strong (higher p-value) for women living within 5 or 1 km of an AQMS.

Conclusions

The two exposure models tended to give consistent results in terms of association with birth weight, despite the moderate concordance between exposure estimates.     

Prenatal Exposure to Nonpersistent Chemical Mixtures and Fetal Growth: A Population-Based Study

Background: Prenatal exposure to mixtures of nonpersistent chemicals is universal. Most studies examining these chemicals in association with fetal growth have been restricted to single exposure models, ignoring their potentially cumulative impact.Objective: We aimed to assess the association between prenatal exposure to a mixture of phthalates, bisphenols, and organophosphate (OP) pesticides and fetal measures of head circumference, femur length, and weight.Methods: Within the Generation R Study, a population-based cohort in Netherlands (n=776), urinary concentrations of 11 phthalate metabolites, 3 bisphenols, and 5 dialkylphosphate (DAP) metabolites were measured at <18, 18–25, and >25 weeks of gestation and averaged. Ultrasound measures of head circumference, femur length, and estimated fetal weight (EFW) were taken at 18–25 and >25 weeks of gestation, and measurements of head circumference, length, and weight were performed at delivery. We estimated the difference in each fetal measurement per quartile increase in all exposures within the mixture with quantile g-computation.Results: The average EFW at 18–25 wk and >25wk was 369 and 1,626g, respectively, and the average birth weight was 3,451g. Higher exposure was associated with smaller fetal and newborn growth parameters in a nonlinear fashion. At 18–25 wk, fetuses in the second, third, and fourth quartiles of exposure (Q2–Q4) had 26g [95% confidence intervals (CI):−38, −13], 35g (95% CI: −55, −15), and 27g (95% CI: −54, 1) lower EFW compared with those in the first quartile (Q1). A similar dose–response pattern was observed at >25wk, but all effect sizes were smaller, and no association was observed comparing Q4 to Q1. At birth, we observed no differences in weight between Q1–Q2 or Q1–Q3. However, fetuses in Q4 had 91g (95% CI: −258, 76) lower birth weight in comparison with those in Q1. Results observed at 18–25 and >25wk were similar for femur length; however, no differences were observed at birth. No associations were observed for head circumference.Discussion: Higher exposure to a mixture of phthalates, bisphenols, and OP pesticides was associated with lower EFW in the midpregnancy period. In late pregnancy, these differences were similar but less pronounced. At birth, the only associations observed appeared when comparing individuals from Q1 and Q4. This finding suggests that even low levels of exposure may be sufficient to influence growth in early pregnancy, whereas higher levels may be necessary to affect birth weight. Joint exposure to nonpersistent chemicals may adversely impact fetal growth, and because these exposures are widespread, this impact could be substantial. https://doi.org/10.1289/EHP9178     

生活垃圾焚烧飞灰基本特性及稳定化研究

对飞灰的化学组分和矿物结构、重金属含量及浸出毒性、二恶英类有机物的含量以及稳定化后产物的浸出毒性进行了试验研究,结果表明：焚烧飞灰属于SiO2-Al2O3-Fe2O3金属氧化物体系,具有一定的胶凝活性,重金属Pb、Cd、Zn的浸出浓度超过GB 5085.3—2007危险废物鉴别标准浸出毒性鉴别要求,二恶英毒性当量为553.6 ng/kg,经添加水泥和螯合剂稳定化处理后,重金属浸出毒性满足GB 16889—2008生活垃圾填埋场污染控制标准的入场要求,可直接送填埋场处置,为以后飞灰稳定化研究和应用提供参考。     

Effects of Acute Exposure to Nitrogen Dioxide on Primary Antibody Response

The effects of acute exposure to nitrogen dioxide on primary humoral antibody response to sheep red blood cells in mice were studied. Mice were exposed to 5 ppm, 20 ppm, and 40 ppm nitrogen dioxide for 12 hr. An exposure of 20 ppm or 40 ppm resulted in a significant suppression of antibody responses, but 5 ppm did not affect antibody response. This immunosuppression resulting from nitrogen dioxide exposure was more apparent in males than females. Exposures to 20 ppm nitrogen dioxide for various time intervals revealed that the strongest suppression effect was observed in the group exposed 2 days after antigen injection. A decreased total cell number in the spleen, and more strikingly, in the thymus, was also caused by acute exposure to nitrogen dioxide.     

被动式个体采样器在监测空气中NO2和SO2浓度中的应用

目的探讨用被动式个体采样器进行空气质量监测的可行性。方法在北京的城区和郊区各选择10户家庭,用被动式个体采样器采样,用离子色谱法测定室内、外空气中的NO2和SO2浓度。于2001年和2002年的采暖和非采暖季节各采样1次,每次连续3d。结果用被动式个体采样器采样检测的结果与国家标准方法采样测定的结果差异无统计学意义。室外空气中NO2和SO2的浓度高于室内,其中冬季城区的NO2和SO2,夏季城区的NO2和郊区的SO2,室内外浓度的差异有统计学意义;冬季城区室外大气中NO2和SO2和室内的NO2浓度显著高于郊区,室外大气的SO2浓度是郊区的3．14倍,但是室内SO2的浓度则低于郊区,差异无统计学意义;夏季城区室内外大气中的NO2浓度均显著高于郊区;2002年城区大气环境中SO2浓度比2001年明显下降。结论被动式个体采样器可以用于大气污染物浓度监测。     

Long-Term Exposure to Road Traffic Noise and Incident Diabetes: A Cohort Study

Background: Road traffic noise at normal urban levels can lead to stress and sleep disturbances. Both excess of stress hormones and reduction in sleep quality and duration may lead to higher risk for type 2 diabetes.Objective: We investigated whether long-term exposure to residential road traffic noise is associated with an increased risk of diabetes.Methods: In the population-based Danish Diet, Cancer and Health cohort of 57,053 people 50–64 years of age at enrollment in 1993–1997, we identified 3,869 cases of incident diabetes in a national diabetes registry between enrollment and 2006. The mean follow-up time was 9.6 years. Present and historical residential addresses from 1988 through 2006 were identified using a national register, and exposure to road traffic noise was estimated for all addresses. Associations between exposure to road traffic noise and incident diabetes were analyzed in a Cox regression model.Results: A 10-dB higher level of average road traffic noise at diagnosis and during the 5 years preceding diagnosis was associated with an increased risk of incident diabetes, with incidence rate ratios (IRR) of 1.08 (95% CI: 1.02, 1.14) and 1.11 (95% CI: 1.05, 1.18), respectively, after adjusting for potential confounders including age, body mass index, waist circumference, education, air pollution (nitrogen oxides), and lifestyle characteristics. After applying a stricter definition of diabetes (2,752 cases), we found IRRs of 1.11 (95% CI: 1.03, 1.19) and 1.14 (95% CI: 1.06, 1.22) per 10-dB increase in road traffic noise at diagnosis and during the 5 years preceding diagnosis, respectively.Conclusion: Exposure to residential road traffic noise was associated with a higher risk of diabetes. This study provides further evidence that urban noise may adversely influence population health.     

Nitrogen Dioxide Exposure Assessment and Cough among Preschool Children

The association between exposure to ambient air nitrogen dioxide and cough was evaluated in a panel study among 162 children aged 3-6 y. The weekly average nitrogen dioxide exposure was assessed with Palmes-tube measurements in three ways: (1) personally, (2) outside day-care centers, and (3) inside day-care centers. Ambient air nitrogen dioxide concentrations were obtained from the local network that monitored air quality. The parents recorded cough episodes daily in a diary. The risk of cough increased significantly (relative risk = 3.63; 95% confidence interval = 1.41, 9.30) in the highest personal nitrogen dioxide exposure category in winter, and a nonsignificant positive trend was noted for the other assessment groups. In spring, risk increased nonsignificantly in all exposure-assessment groups, except for the fixed-site monitoring assessment. It is important that investigators select an exposure-assessment method sufficiently accurate to reflect the effective pollutant dose in subjects.