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PubMedDate not supplied

The effect of environmental pollution on the respiratory system of lignite miners: a diachronic study.

BACKGROUND: It is not known whether working in surface lignite mines can cause x-ray lesions or disorders of respiratory function. OBJECTIVES: The aim of the study was to investigate the diachronic impact of environmental pollution on the respiratory system of lignite miners at mines in Eordea, Greece. METHODS: Cases of 199 workers (Group A) residing permanently in the Eordea valley and 151 (Group B) living outside the Eordea valley were studied during Phase I and then re-examined after three years (Phase II). These cases were compared to those of 71 office workers living in Eordea valley (Group C) and to 96 living in Grevena, a region without pollution (Group D). The study included the completion of the MRC questionnaire for the detection of respiratory diseases, pulmonary function tests, measurement of diffusion capacity, otorhinolaryngologic examination, rhinomanonetry as well as chest and paranasal cavity X-rays. RESULTS: Chronic bronchitis was reported by 26.8%, 24.8%, 17.9% and 10.6% respectively of the subjects of groups A, B, C and D according to the answers of the questionnaire (p<0.001). The spirometry and diffusion capacity findings presented no considerable differences either in the 4 groups or between phases I and II of the study. The main problems were detected in the upper airways. A very high prevalence of severe nasal obstruction (73%, 71.2%, 55.7% and 19.3% in Groups A, B, C and D respectively) was detected. Furthermore, a high percentage of atrophic rhinitis (14%) was detected both among workers (Groups A and B) and subjects living in the Eordea valley who participated as controls (Group C). From the X-rays, hypertrophy of nasal turbinates-cartilage and polyposis was observed as follows: Group A: 53.9%, Group B: 48.1%, Group C: 46.5% and Group D: 20.3% (p<0.001). The findings related to the upper respiratory system may be due to excessive pollution by airborne particles (fly ash) pollution in the region and particularly to chromium, nickel, cobalt and lead found at high concentration levels in airborne dust. A marked association between the total air-flow in the nose and the mid-expiratory flow (p<0.01) was detected. CONCLUSIONS: We conclude that subjects working in lignite mines under conditions of excessive pollution by airborne contaminants have a high prevalence of atrophic rhinitis and, in addition to other standard examinations, should undergo rhinomanometry testing and X-ray imaging of the paranasal cavities.

Adult↗
PubMed2005

The relationship of air pollution to the prevalence of allergic diseases in Taichung and Chu-Shan in 2002.

This study was conducted in order to determine the relationship between air pollution and the varying prevalence of allergic diseases in the city of Taichung and the rural town of Chu-Shan. We used questionnaires to screen children aged from 7 to 15 years in Taichung and Chu-Shan and compared the results from these 2 areas with the factors related to air pollution. The study included 11,580 children in Taichung and 2621 children in Chu-Shan. In Taichung, the prevalence of asthma was 7.0%, of allergic rhinitis 27.6% and of atopic dermatitis 3.4%. In Chu-Shan, the prevalence of asthma was 5.6%, of allergic rhinitis 21.8% and of atopic dermatitis 3.3%. We also collected data on the concentration of air pollutants in the 2 areas over a 1-year period from January to December 2001 and compared the average annual concentrations of various pollutants. Compared with Chu-Shan, Taichung had higher air concentrations of nitric oxide (NO; 11.47 +/- 4.75 vs 5.07 +/- 2.81 ppb), carbon monoxide (CO; 0.78 +/- 0.19 vs 0.59 +/- 0.12 ppm), nitrogen dioxide (NO(2); 24.99 +/- 6.8 vs 21.45 +/- 7.87 ppb) and sulfur dioxide (SO(2); 2.58 +/- 1.0 vs 2.44 +/- 0.88 ppb). Student's t test results showed that CO and NO were related significantly to the prevalence of allergic disease (p<0.005). The prevalence of both asthma and allergic rhinitis is higher in Taichung than in Chu-Shan, a finding that could be related to higher levels of some air pollutants in the urban location.

Adolescent↗
PubMed2004

Impact of air pollution on floral morphology of Cassia siamea Lamk.

Cassia siamea plants growing at two different sites (polluted and non-polluted) on two important roads of Agra city exhibited significant differences in their flowering phenology and floral morphology. The flowering in plants growing at polluted site is delayed and there was a marked reduction in flowering density, flowering period, size of floral parts, pollen fertility, fruit and seed-set. SEM observations revealed the presence of well developed glandular structures and reduction in the number and size of large stomata on the anther surface at polluted site. These changes were found to be closely associated with the extent of air pollution caused mainly by significant in the number of automobiles.

Air Pollutants↗
PubMed2005

Propagation of uncertainty in diffuse pollution into water quality predictions: application to the River Dender in Flanders, Belgium.

The uncertainty of water quality predictions caused by uncertainty in the inputs related to emissions of diffuse pollution is analysed. An uncertainty analysis of the effects of diffuse pollution is essential to compare the cost and benefits of measures to lower those emissions. We focus on diffuse nitrate pollution due to fertiliser use. Using an efficient Monte Carlo method and Latin Hypercube sampling, the contribution to the overall uncertainty by each of the inputs is calculated. The modelling environment is ESWAT, an extension of SWAT, which allows for integral modelling of the water quantity and quality processes in river basins. The diffuse pollution sources are assessed by considering crop and soil processes. The crop simulations include growth, uptake of water and nutrients and several land management practices. The in-stream water quality model is based on QUAL2E. The spatial variability of the terrain strongly affects the non-point source pollution processes. The methodology is applied to the Dender basin in Belgium. Eight inputs have significant influence on the time that the nitrate content in the river is higher than 3 mg/l. The uncertainty analysis indicated wide uncertainty bounds (95% percentile bounds differ up to +/-50% from the average NO3 predictions).

Belgium↗
PubMed2005

Review of attitudes and awareness in the agricultural industry to diffuse pollution issues.

The Scottish Executive considers 'Diffuse Pollution from Agricultural Enterprises' as a priority issue over the next 5-10 years and recognises the need to improve knowledge transfer, advice and training amongst farmers, crofters, contractors and advisers. The Scottish Environment Protection Agency commissioned SAC to survey advisory staff on diffuse pollution issues, mitigation measures and delivery of environmental advice to the farming industry. This showed that the impact of agricultural diffuse pollution on the environment is considered a serious problem as is the future impact of legislation on farm business. There is an urgent requirement to raise advisers' awareness of environmental legislation and of mitigation measures. Advisers consider that farmers have limited awareness of diffuse pollution problems but those that do would consider the impact on the environment to be serious. There is a lack of knowledge on the effectiveness of pollution mitigation measures. Better technical information, supported by research, is required. This information is best conveyed to advisers via the internet, technical notes and directly by environmental specialists and delivered on to farmers by farm visits. Lack of funds prevents most farmers adopting best management practices and more than 80% of advisers consider that environmental advice should be free.

Agriculture↗
PubMed2005

PAHs pollution from traffic sources in air of Hangzhou, China: trend and influencing factors.

PAHs pollution in air of arterial roads was investigated from October 1998 to October 2001 in Hangzhou, China. The results showed that sigma10 PAHs was 13-36 microg/m3, among which, BaP, a strong carcinogenic kind ranged from 0.034 microg/m3 to 0.12 microg/m3. PAHs pollutions in four seasons were winter > autumn > spring-summer. The annual averages of sigmaPAHs concentration were 25 microg/m3 for 1999, 28 microg/m3 for 2000, and 29 microg/m3 for 2001, respectively. Leaded gasoline was banned in December 1998 in Hangzhou, thus comparative measurements with PAHs in leaded and lead-free gasoline powered motor exhausts made it certain that the use of lead-free gasoline leaded to a heavier PAHs pollution in roadside air from December, 1998, in China, and sigmaPAHs in air samples after the lead-banning were more than twice of that in samples before the action. For the large contribution of vehicle discharge to air pollution in roadside, further research was performed to suggest the factors influencing PAHs distribution in vehicle exhaust in order to control air pollution effectively. Compared to gasoline engines, emissions from diesel engines were less toxic, although they might produce more PAHs. Of the same vehicular and oil type, automobiles of longer mileages produced more toxic PAHs. PAHs distributions in the vehicular exhausts were related to the oil type. Large difference was found in the abundance of 3-, 5- and 6-ring PAHs between exhausts from gasoline and diesel oil engines. Diesel oil engines produced relative lighter PAHs such as NAPH, ACEN, FLUOR, while gasoline engines emitted heavier kinds such as BkF, IN and BP. The automobile produced more PAHs with the increase of mileage especially FLUR, PY, BaP, BP. Some significant ratios for traffic source in Hangzhou such as PHEN/AN, FLUR/PY, IN/BP were 0.50-4.3, 0.58-7.4, 0.51-1.5, respectively. A source fingerprint for vehicle exhausts of a mixture of vehicle and oil types in the city district for light-duty vehicle was the abundance of BaA, followed by NAPH, BP, IN. 4-ring PAHs such as FLUR, PY, BaA and CHRY were the most predominant kinds followed by 6-ring PAHs(BP, IN).

Air Pollutants↗
PubMed2005

[Investigation on removal of organic pollutions in landfill leachate in Guangzhou City, China].

A set of simultaneous oxic and anaerobic bioreactor was used to treat the landfill leachate generated from Datianshan Landfill in Guangzhou, China. The results demonstrate that the average effluent concentration of COD and NH4(+)-N was 129 mg x L(-1) and 10 mg x L(-1) respectively, both of them can be controlled below the Chinese second grade discharge permit levels (COD(Cr) < 300 mg x L(-1), NH4(+)-N < 25 mg x L(-1)) for this kind of wastewater. Moreover, the GC-MS analysis was used to measure the organic pollutants contained in landfill leachate. 87 kinds of organic matters in this kind of landfill leachate were detected and discovered, and 16 of them belong to the list of environmental priority pollutants which is considered by EPA in USA. As a result, 31 kinds of totally 87 kinds of organic pollutants were completely removed, 14 kinds of totally 87 kinds of organic pollutants were removed more than 80%, the removal efficiencies of 25 kinds of organic pollutants reached over 50%.

Biodegradation, Environmental↗
PubMed2005

Spatial variability of characteristics and origins of urban wet weather pollution in combined sewers.

An experimental on-site observatory of urban pollutant loads in combined sewers was created in the centre of Paris to quantify and characterise the dry and wet weather flow in relation to spatial scale. Eight rainfall events were studied from April 2003 to May 2004. Samples were analysed for suspended solids, organic matter, nitrogen and heavy metals. Results confirm the extent of wet weather pollution. They have shown the relative homogeneity of SS and organic matter characteristics from one urban catchment area to another. Two groups of heavy metals were identified. The first one concerns Cu, which has a higher concentration in wet weather flow (WWF) than in dry weather flow (DWF), and runoff. The second includes Cd, Pb and Zn, where higher concentrations were measured in urban runoff than in WWF and DWF. A first evaluation of contribution of wastewater, urban runoff and sewer deposit erosion sources to wet weather pollution was established and has highlighted the contribution of wastewater and sewer deposits to this pollution. However, it has shown that sewer deposit erosion remains an important source of wet weather pollution at different spatial scales.

Cities↗
PubMed2005

[Horizontal transfer of environmental pollutant-degrading gene and application in bioremediation].

Horizontal gene transfer, unlike vertical gene transfer, is a means of genetic communication in bacteria. In the special polluted environment, horizontal transfer of polluted-degrading gene has significant functions. Study on horizontal transfer of degrading gene in polluted environment may deepen our understanding of the mechanism of bacterial adaptation to the organic-polluted environment. In the practical application in bioremediation, horizontal transfer of degrading gene can be regulated to promote degrading ability of microorganisms. In this article, we will review the advances in the study on mechanisms of genetic interactions among bacteria, the effect of degrading gene transfer in contaminated environment on microorganisms'adaptation to contaminated environment and the degradation of the pollutants.

Adaptation, Physiological↗
PubMed2005

[Air pollution and respiratory symptoms of school children in a panel study in Seoul].

OBJECTIVES: The aim of this study was to assess the effect of air pollution on the daily respiratory symptoms of elementary school children in Seoul. METHODS: Using the panel study design, we collected diary data for the children's respiratory symptoms during the 1st day approximately 15th day of April, July, October and December in 2003 among the 2nd and 3rd grade elementary school students. We merged the respiratory symptom data with the ambient air pollution data that was monitored by Ministry of Environment. Using a generalized estimate equation, we evaluated the relationship between the daily symptoms of the subjects and the exposure to air pollution after controlling for various potential confounders. RESULTS: The nitrogen dioxide (NO2) exposure of the current day significantly increased the upper respiratory symptoms (adjusted odds ratio=1.12, 95% CI=1.01-1.24) and the lower respiratory symptoms (adjusted odds ratio=1.18, 95% CI=1.06-1.31) in the elementary school children. The sulfur dioxide (SO2) and carbon monoxide (CO) exposure in the current day was associated with the lower respiratory symptoms (adjusted odds ratio=1.12, 95% CI=1.01-1.25 for SO2; adjusted odds ratio=1.16, 95% CI=1.02-1.32 for CO). CONCLUSIONS: We found that exposure to air pollution affects the daily respiratory symptoms in children. This study suggests that the effect on children's health? due to the short term changes in air pollution levels needs to be considered as an important public health problem.

Air Pollution, Indoor↗
PubMed2005

[Degradation regulation of fenthion and chlorfenvinfos combined pollutants in red soil].

The degrading regulations of combined pollutants of chlorfenvinfos and fenthion in red soil were studied, in which soil incubation, gas chromatography with nitrogen-phosphorus detection for analysis are utilized. The main conclusions drawn are as follows: under combined pollution condition, the degrading amount of fenthion was significantly higher than that of fenthion alone in soil; under saturated soil humidity, the degrading amount of fenthion was less changed, while that of chlorfenvinfos was increased by 33.3% - 1250%. Soil drought made degradation amount of fenthion decreased a little, while made chlorfenvinfos increased significantly prior to the 21st day after addition of pesticide; nitrogen fertilizer application stimulated both fenthion and chlorfenvinfos degraded; the chemical degrading amount of fenthion in soil with organic matter eliminated was decreased by 22.4% - 30.8%, while that of chlorfenvinfos was increased 42.1% - 2370% at the earlier stage, and was decreased 11% - 17.3% at the later stage. Therefore, there are differences of degrading regulation between single pesticide pollutant and combined pesticide pollutants in soil, and the degradation of organophosphorus pesticides in combined pollutants are influenced with each other.

Biodegradation, Environmental↗
PubMed2006

Application of DALYs in measuring health effect of ambient air pollution: a case study in Shanghai, China.

OBJECTIVE: To investigate the effect of ambient air pollution on human health and the subsequent disability-adjusted life years (DALYs) lost in Shanghai. METHODS: We used epidemiology-based exposure-response functions to calculate the attributable number of cases due to air pollution in Shanghai in 2000, and then we estimated the corresponding DALYs lost in Shanghai based on unit DALYs values of the health consequences. RESULTS: Ambient air pollution caused 103,064 DALYs lost in Shanghai in 2000. Among all the health endpoints, premature deaths and chronic bronchitis predominated in the value of total DALYs lost. CONCLUSION: The air pollution levels have an adverse effect on the general population health and strengthen the rationale for limiting the levels of air pollution in outdoor air in Shanghai.

Air Pollution↗
PubMed2006

[PCBs concentrations in human milk collected from a polluted area--exposure risk for feeding infants].

OBJECTIVE: To determine the concentration of PCBs and the distribution of dioxin-like compounds in human milk collected from a polluted area where discarded electronic equipment is dismantled, and to evaluate the risk for feeding infants. METHODS: The authors collected 20 and 12 milk samples from the polluted area and nearby town, respectively. Milk samples were analyzed for total PCBs (t-PCBs) by gas chromatography, and two mixed milk samples from the two areas were detected the distribution of dioxin-like compounds. RESULTS: t-PCBs in human milks of polluted area and control area were 0.39 - 3.92 microg/g fat and 0.46 microg/g (only one sample was detectable), respectively. The TEQ of PCB126 contribute to total TEQ of dioxin-like compounds was similar to other countries and regions. The TEQs of PCBs of the polluted and control area were 59 pg/g fat and 6 pg/g fat, respectively. CONCLUSION: The TEQ of PCBs of polluted area was much higher than other countries and regions, and the dioxin-like compounds intake of infants was much higher than the Tolerable Daily Intake (TDI) for dioxin recommended by WHO.

Adult↗
PubMed2006

[Treatment performance and enhancement of subsurface constructed wetland treating polluted river water in winter].

Treatment performance of subsurface constructed wetland treating polluted river water in winter was studied. When hydraulic loading fell down from 30cm/d to 15cm/d, the average removal rates of ammonium nitrogen and COD rose up from 14% and 20% to 39% and 31% respectively. Water temperature had great influence on ammonium nitrogen removal. Membrane overlay on the wetland could improve pollutants removal efficiently. The average removal rates of ammonium nitrogen and COD could rise up from 29.4% and 29% to 67.6% and 46.6% respectively. Microorganism enzyme activity experiments show that increase of microorganism activity caused by membrane overlay contributed a lot to pollutants removal enhancement. Urease activity rose up from 0.025 mg/(g x d) to 0.037 mg/(g x d) with membrane overlay, and dehydrogenase activity rose up from 0.17 microL/(d x g) to 4.54 microL/(d x g) with membrane overlay. The pollutants releasing experiment of aquatic plants show that faded plants would release a lot of pollutants into water. Therefore, plants harvest was necessary in autumn.

Ammonia↗
PubMed1990

[Current status of air pollution in Sao Paulo, Brazil: effects and problems associated with the introduction of ethanol-fueled motor vehicles].

Recently suggestions have been advanced that alternative fuels including ethanol, methanol or methane instead of so called "fossil fuels" may help improve the current conditions of air pollution. According to results of general survey in Sao Paulo, since their introduction in 1978, ethanol-fueled cars have increased their share to almost 50% of all light vehicles in 1983. The current status of air pollution in Sao Paulo metropolitan area (SPMA) is described in relation to the use of such alternative fuel. The average concentrations in air of SO2 and lead have been decreasing drastically during the period of 1982-88, whereas non-methane hydrocarbon, NO2 and O3 levels have been increasing to attain the worst levels in the world as indicated in Fig. 2. The use of ethanol-fuel, which contains less sulphate and lead, is thought to have contributed more or less to the above reductions of SO2 and lead in the air. However, the pollutants that have increased may derive mainly from diesel and gasoline exhausts of heavy vehicles. The general state of air pollutions appears not to have been improved, suggesting the difficulty in resolving air pollution issues. On the other hand, a current problem specific to ethanol-fuel is the aldehydes or other carcinogenic components in exhaust. Peak formaldehyde concentration, for example, have been reported to have reached 159 ppb in SPMA, which may be one of the highest levels shown in ambient air.(ABSTRACT TRUNCATED AT 250 WORDS)

Air Pollution↗
PubMed1995

Indoor air pollution and acute lower respiratory infections in the first two years of life.

The relationship between outdoor air pollution and acute respiratory infections (ARI) was previously documented. There are recent indications for connection between indoor air pollution and ARI in infants and young children. The aim of this study was to identify the relationship of indoor air pollutants to acute lower respiratory infection (ALRI) in children (< 2 years). The indoor air pollutants concentrations were measured in the homes of the sample. The sample consisted of 115 children (< 2 years) representing the control group (24), ALRI but no pneumonia (24), pneumonia (30), severe pneumonia or very severe disease (37). Air sampling was performed to measure the concentration of total suspended particulates (TSP), SO2 and CO. These pollutants were found in higher concentrations in cases' homes (52.46 +/- 19.68 microg/m3, 298.15 +/- 669.37 microg/m3, and 1.92 +/- 3.60 ppm) than in controls' homes (31.92 +/- 8.76 microg/m3, not detected, and 0.33 +/- 1.63 ppm respectively). Whereas SO2 was detected only in houses using kerosene, TSP and CO were detected with the different types of cooking fuels. Their mean concentrations were highest for biomass (88.86 +/- 13.30 microg/m3 and 9.29 +/- 2.50 ppm) and lowest for gas (40.78 +/- 15.25 microg/m3 and 0.76 +/- 2.19 ppm). Measures to improve indoor air quality are highly required.

Acute Disease↗
PubMedDate not supplied

Ozone, air pollution, and respiratory health.

Of the outdoor air pollutants regulated by the Clean Air Act of 1970 (and recently revised in 1990), ozone has been the one pollutant most difficult to control within the federal standards. The known human health effects are all on the respiratory system. At concentrations of ozone which occur during summer air-pollution episodes in many urban metropolitan areas of the United States, a portion of the healthy population is likely to experience symptoms and reversible effects on lung function, particularly if exercising heavily outdoors. More prolonged increase in airway responsiveness and the presence of inflammatory cells and mediators in the airway lining fluid may also result from these naturally occurring exposures. Serial exposures to peak levels of ozone on several consecutive days are more characteristic of pollution episodes in the Northeast United States and may be associated with recurrent symptoms. No "high-risk" or more sensitive group has been found, in contrast to the case of sulfur dioxide, to which asthmatics are more susceptible than normals. The occurrence of multiple exposure episodes within a single year over many years in some areas of California has led to studies looking for chronic effects of ozone exposure on the lung. To date, no conclusive studies have been reported, although further work is under way. Much of what we know about the effects of this gas on the lung are based on controlled exposures to pure gas within an environmental exposure laboratory. Interactions between substances which commonly co-occur in air-pollution episodes are also under investigation.

Air Pollution↗
PubMed1991

Stochastic microenvironment models for air pollution exposure.

Exposure assessment is a crucial link in air pollution risk assessment and management. With the recent advances in instrumentation, it has become possible to measure air pollution exposures in the vicinity of the individual human subjects, using either personal monitoring or microenvironment monitoring. For many important pollutants such as CO, NO2, and VOC, the air pollution exposure depends crucially on the location and activity of the individual: indoor versus outdoor, smoking versus not smoking, etc. The stochastic microenvironment models were developed to relate air pollution exposure to the location and activity. We review the two major existing models, the Cartesianization method (Duan, 1980, 1982, 1987) and SHAPE (Ott, 1981, 1982, 1984), and compare their assumptions and implications. We also propose a new model, the variance components model, which includes both Cartesianization and SHAPE as special cases. The variance components model considers both long-term average concentrations and short-term fluctuations. The Cartesianization focuses on long-term averages, while SHAPE focuses on short-term fluctuations. We propose to choose among the three models by examining the variance function which relates variability to averaging time. The theory is applied to the data collected from U.S. EPA's Washington CO Study, with the variance function estimated using Carroll and Ruppert's (1984) transform-both-sides regression model and Duan's (1983) smearing estimate. For the microenvironment in transit, both long-term averages and short-term fluctuations are important.

Air Pollution↗