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PubMedDate not supplied

Asthma and low level air pollution in Helsinki.

The effects of relatively low levels of air pollution and weather conditions on the number of patients who had asthma attacks and who were admitted to a hospital were studied in Helsinki during a 3-y period. The number of admissions increased during cold weather (n = 4,209), especially among persons who were of working age but not among children. Even after standardization for temperature, all admissions, including emergency ward admissions, were significantly correlated with ambient air concentrations of nitrogen dioxide (NO2), nitric oxide (NO), sulfur dioxide (SO2), carbon monoxide (CO), ozone (O3), and total suspended particulates (TSP). Regression analysis revealed that NO and O3 were most strongly associated with asthma problems. Effects of air pollutants and cold were maximal if they occurred on the same day, except for O3, which had a more pronounced effect after a 1-d lag. The associations between pollutants, low temperature, and admissions were most significant among adults of working age, followed by the elderly. Among children, only O3 and NO were significantly correlated with admissions. Levels of pollutants were fairly low, the long-term mean being 19.2 micrograms/m3 for SO2, 38.6 micrograms/m3 for NO2, 22.0 micrograms/m3 or O3, and 1.3 mg/m3 for CO. In contrast, the mean concentration of TSP was high (76.3 micrograms/m3), and the mean temperature was low (+ 4.7 degrees C). These results suggest that concentrations of pollutants lower than those given as guidelines in many countries may increase the incidence of asthma attacks.

Adolescent↗
PubMedDate not supplied

Respiratory hospital admissions associated with PM10 pollution in Utah, Salt Lake, and Cache Valleys.

This study assessed the association between respiratory hospital admissions and PM10 pollution in Utah, Salt Lake, and Cache valleys during April 1985 through March 1989. Utah and Salt Lake valleys had high levels of PM10 pollution that violated both the annual and 24-h standards issued by the Environmental Protection Agency (EPA). Much lower PM10 levels occurred in the Cache Valley. Utah Valley experienced the intermittent operation of its primary source of PM10 pollution: an integrated steel mill. Bronchitis and asthma admissions for preschool-age children were approximately twice as frequent in Utah Valley when the steel mill was operating versus when it was not. Similar differences were not observed in Salt Lake or Cache valleys. Even though Cache Valley had higher smoking rates and lower temperatures in winter than did Utah Valley, per capita bronchitis and asthma admissions for all ages were approximately twice as high in Utah Valley. During the period when the steel mill was closed, differences in per capita admissions between Utah and Cache valleys narrowed considerably. Regression analysis also demonstrated a statistical association between respiratory hospital admissions and PM10 pollution. The results suggest that PM10 pollution plays a role in the incidence and severity of respiratory disease.

Adolescent↗
PubMedDate not supplied

Evidence for interaction between air pollution and high temperature in the causation of excess mortality.

Studies have demonstrated repeatedly that air pollution in Athens is associated with a small but statistically significant increase in mortality. Extremely high air temperatures can also cause excess mortality. This study investigated whether air pollution and air temperature have synergistic effects on excess mortality in Athens. Data concerning the increased number of deaths in July 1987 (when a major "heat wave" hit Greece) were compared to the deaths in July of the 6 previous years. This comparison revealed a greater increase in the number of deaths in Athens (97%), compared to all other urban areas (33%) and to all non-urban areas (27%). Data on the daily levels of smoke, sulfur dioxide, and ozone; the number of deaths that occurred daily; and meteorological variables were collected for a 5-y period. The daily value of Thom's discomfort index was calculated. Multiple linear regression models were used to investigate main and interactive effects of air temperature and Thom's discomfort index and air pollution indices. The daily number of deaths increased by more than 40 when the mean 24-h air temperature exceeded 30 degrees C. The main effects of an air pollution index are not statistically significant, but the interaction between high levels of air pollution and high temperature (> or = 30 degrees C) are statistically significant (p < .05) for sulfur dioxide and are suggestive (p < .20) for ozone and smoke. Similar results were obtained when the discomfort index was used, instead of temperature in the models.

Air Pollutants↗
PubMedDate not supplied

The South Karelia Air Pollution Study: changes in respiratory health in relation to emission reduction of malodorous sulfur compounds from pulp mills.

The authors assessed the health effects of emission reduction of malodorous sulfur compounds in a prospective cohort study with a controlled natural experiment. A total of 810 subjects (83%) participated in the follow up: 316 from the severely polluted, 306 from the moderately polluted, and 188 from the nonpolluted communities. In the severely polluted community, the annual ambient air concentration of total reduced sulfur compounds decreased from 11 microg/m3 to 6 microg/m3. Compared with the nonpolluted community, the relative decrease in acute respiratory infections, adjusted for a change in smoking habits, was 0.53 episodes/person-year (95% confidence interval = 0.22, 0.83) in the severely polluted community and 0.36 episodes/person-year (95% confidence interval = 0.06, 0.66) in the moderately polluted community. In addition, the frequency of nasal symptoms (p = .004) and cough (p = .037) decreased significantly. The results are consistent with the hypothesis that exposure to malodorous sulfur compounds increases the risk of acute respiratory infections and symptoms of the respiratory tract.

Acute Disease↗
PubMedDate not supplied

Air pollution is associated with increased level of exhaled nitric oxide in nonsmoking healthy subjects.

The authors sought to determine which air pollutant is responsible for the increase in exhaled nitric oxide observed in healthy subjects. Exhaled nitric oxide was measured in 16 nonsmoking healthy subjects on 14 workdays, during which there were varying air-pollution levels. Contamination of samples by ambient nitric oxide was excluded. The baseline value of exhaled nitric oxide, determined at times when outdoor air pollution was low, ranged from 7 to 43 ppb (mean = 28+/-5 ppb). The daily value of exhaled nitric oxide (range = 5-60 ppb) was associated positively with ambient carbon monoxide (r = .85) and nitric oxide (r = .81). Exposure during the morning hours to high levels of outdoor pollution was associated with increased exhaled nitric oxide (i.e., 50% above baseline), which persisted for up to 5 h (i.e., 32% above baseline). These results indicated that exhaled nitric oxide levels represent a useful biomonitor of individual exposure to air pollutants.

Adult↗
PubMed1989

Air hygiene in a pullet house: spatial homogeneity of aerial pollutants.

1. The spatial distribution of aerial pollutants was measured in a large deep-litter pullet house, initially holding 10,000 birds, at 12 sites within the birds' breathing zone: on 6 occasions when the birds were between 8 and 27 d of age and on two occasions when the birds were 29 and 34 d of age and the flock size was halved. 2. The distribution of most pollutants appeared uniform, implying that all sites could be considered representative of the overall concentration of pollutant. 3. The concentration of ammonia differed between sites, probably because of local variations in the rate of release from the litter. The number concentration of non-respirable particles (greater than 5 microns in diameter) became heterogeneous when the flock size was halved. 4. The operation of two punka fans had no effect on the spatial distribution of aerial pollutants, but increased the maximum air speed from 0.08 to 0.16 m/s. 5. Recommendations are given for the minimum number of sampling sites necessary for a predetermined level of statistical accuracy. Eight sites at least are recommended for most aerial pollutants, though more are needed for the concentration of gaseous ammonia.

Air Pollutants↗
PubMed1975

Prevention of sewage pollution by stabilization ponds.

Water is polluted when it constitutes a health hazard or when its usefulness is impaired. The major sources of water pollution are municipal, manufacturing, mining, steam, electric power, cooling and agricultural. Municipal or sewage pollution forms a greater part of the man's activity and it is the immediate need of even smaller communities of today to combat sewage pollution. It is needless to stress that if an economic balance of the many varied services which a stream or a body of water is called upon to render is balanced and taken into consideration one could think of ending up in a wise management programme. In order to eliminate the existing water pollutional levels of the natural water one has to think of preventive and treatment methods. Of the various conventional and non-conventional methods of sewage treatment known today, in India, where the economic problems are complex, the waste stabilization ponds have become popular over the last two decades to let Public Health Engineers use them with confidence as a simple and reliable means of treatment of sewage and certain industrial wastes, at a fraction of the cost of conventional waste treatment plants used hitherto. A waste stabilization pond makes use of natural purification processes involved in an ecosystem through the regulating of such processes. The term "waste stabilization pond" in its simplest form is applied to a body of water, artificial or natural, employed with the intention of retaining sewage or organic waste waters until the wastes are rendered stable and inoffensive for discharge into receiving waters or on land, through physical, chemical and biological processes commonly referred to as "self-purification" and involving the symbiotic action of algae and bacteria under the influence of sunlight and air. Organic matter contained in the waste is stabilized and converted in the pond into more stable matter in the form of algal cells which find their way into the effluent and hence the term "stabilization pond".

India↗
PubMed2002

Systemic inflammatory response induced by particulate matter air pollution: the importance of bone-marrow stimulation.

The relationship between the level of particulate air pollution (PM(10)) and the mortality and morbidity rates from respiratory and cardiovascular diseases is well established, but the biological mechanisms responsible for these associations are still unclear. The injurious effects of particulate air pollution may be either local (in the lung) or systemic. Bone-marrow release of leukocytes and platelets is an important component of the systemic inflammatory response. We have developed methods to quantify bone-marrow stimulation and showed in animals that acute exposure to ambient particles accelerates the transit of polymorphonuclear leukocytes (PMN) through the marrow whereas chronic exposure expands the size of the bone marrow pool of PMN. Human studies showed that an episode of severe air pollution stimulates the bone marrow in a manner similar to that observed in animals. In vitro and in vivo studies suggest that alveolar macrophage produce the mediators implicated in the bone marrow response to ambient particles. Cytokines produced in the lung due to deposition of ambient particles also appear in the circulation. In vitro and in vivo studies have shown that PMN recently released from the bone marrow preferentially sequester in pulmonary capillaries, are less chemotactic, and contain more damaging granular enzymes, all factors that potentate their ability to damage alveolar tissue. In animals that naturally develop atherosclerosis, deposition of ambient particles in the lung causes progression of atherosclerotic plaques with phenotypic changes in atherosclerotic plaques characteristic of lesions vulnerable to rupture. We conclude that exposure to ambient particulate matter air pollution induces a systemic inflammatory response that includes the release of inflammatory mediators into the circulation that stimulate the bone marrow to release leukocytes and platelets. We postulate that this systemic response to particulate air pollution augments lung inflammation and changes the phenotype of atherosclerotic plaques to make them more vulnerable to rupture.

Air Pollutants↗
PubMed2005

Are Drosophila a useful model for understanding the toxicity of inhaled oxidative pollutants: a review.

Oxidative atmospheric pollutants represent a significant stress and cause injury to both vertebrate and invertebrate species. In both, the biosurfaces of their respiratory apparatus are directly exposed to oxidizing pollutant-induced stresses. Respiratory-tract surfaces contain integrated antioxidant systems that appear to provide a primary defense against environmental insults caused by inhaled atmospheric reactive oxygen species (ROS) and reactive nitrogen species (RNS), whether gaseous or particulate. When the biosurface antioxidant defenses are overwhelmed, oxidative and nitrosative stress to the acellular and cellular components of the exposed biosurfaces can ensue via direct chemical reactions that lead to the induction of inflammatory, adaptive, injurious, and reparative processes. The study of model invertebrates (e.g., Drosophila) has a long history of yielding valuable insights into both fundamental biology and pathobiology. Mutants and/or transgenic insects, with specific alterations in key components of innate and/or adaptive antioxidant defense systems and immune genes, offer opportunities to dissect the complex systems that maintain respiratory tract surface defenses against environmental oxidants and the ensuing host responses. In this article, we use a comparative absfont approach to consider interactions of atmospheric oxidant pollutants with selected biosystems. We focused primarily on ozone (O(3)) as the pollutant, vertebrate and invertebrate respiratory tracts as the exposed biosystems, and nonenzymatic micronutrient antioxidants as significant contributors to overall antioxidant defense strategies. We present parallels among these diverse organisms with regard to their protective strategies against environmental atmospheric oxidants, with particular focus given to using the invertebrate Drosophila as a potentially useful model for vertebrate respiratory-tract responses to inhaled oxidants specifically and pollutants in general. We conclude that the insect respiratory system has considerable promise toward understanding novel aspects of vertebrate respiratory tract responses to inhaled oxidative environmental challenges.

Air Pollutants↗
PubMed2000

Effect of the fine fraction of particulate matter versus the coarse mass and other pollutants on daily mortality in Santiago, Chile.

Daily counts of non-accidental deaths in Santiago, Chile, from 1988 to 1996 were regressed on six air pollutants--fine particles (PM2.5), coarse particles (PM10-2.5), CO, SO2, NO2, and O3. Controlling for seasonal and meteorological conditions was done using three different models--a generalized linear model, a generalized additive model, and a generalized additive model on previously filtered data. Single- and two-pollutant models were tested for lags of 1-5 days and the average of the previous 2-5 days. The increase in mortality associated with the mean levels of air pollution varied from 4 to 11%, depending on the pollutants and the way season of the year was considered. The results were not sensitive to the modeling approaches, but different effects for warmer and colder months were found. Fine particles were more important than coarse particles in the whole year and in winter, but not in summer. NO2 and CO were also significantly associated with daily mortality, as was O3 in the warmer months. No consistent effect was observed for SO2. Given particle composition in Santiago, these results suggest that combustion-generated pollutants, especially from motor vehicles, may be associated with increased mortality. Temperature was closely associated with mortality. High temperatures led to deaths on the same day, while low temperatures lead to deaths from 1 to 4 days later.

Adolescent↗
PubMed2001

Assessment of vehicular pollution in China.

As the motor vehicle population in China continues to increase at an annual rate of approximately 15%, air pollution related to vehicular emissions has become the focus of attention, especially in large cities. There is an urgent need to identify the severity of this pollution in China. Based on an investigation into vehicle service characteristics, this study used a series of driving cycle tests of in-use Chinese motor vehicles for their emission factors in laboratories, which indicated that CO and HC emission factors are 5-10 times higher, and NOx 2-5 times higher, than levels in developed countries. The MOBILE5 model was adapted to the Chinese situation and used to calculate the emission of pollutants from motor vehicles. Results show that vehicle emission is concentrated in major cities, such as Beijing, Guangzhou, Shanghai, and Tianjin. Motor vehicle emissions contribute a significant proportion of pollutants in those cities, with contribution rates of CO and NOx greater than 80% and 40%, respectively, in Beijing and Guangzhou. Urban air quality is far worse than the national ambient air quality standard. In conclusion, although China has a relatively small number of motor vehicles, most of them are concentrated within metropolitan areas, and their emissions are closely related to urban air pollution problems in large cities.

Air Pollutants↗
PubMed2002

Roadside particulate air pollution in Bangkok.

Airborne fine particles of PM(2.5-10) and PM2.5 in Bangkok, Nonthaburi, and Ayutthaya were measured from December 22, 1998, to March 26, 1999, and from November 30, 1999, to December 2, 1999. Almost all the PM10 values in the high-polluted (H) area exceeded the Thailand National Ambient Air Quality Standards (NAAQS) of 120 microg/m3. The low-polluted (L) area showed low PM10 (34-74 microg/m3 in the daytime and 54-89 microg/m3 at night). PM2.5 in the H area varied between 82 and 143 microg/m3 in the daytime and between 45 and 146 microg/m3 at night. In the L area, PM2.5 was quite low both day and night and varied between 24 and 54 microg/m3, lower than the U.S. Environmental Protection Agency (EPA) standard (65 microg/m3). The personal exposure results showed a significantly higher proportion of PM2.5 to PM10 in the H area than in the L area (H = 0.80 +/- 0.08 and L = 0.65 +/- 0.04). Roadside PM10 was measured simultaneously with the Thailand Pollution Control Department (PCD) monitoring station at the same site and at the intersections where police work. The result from dual simultaneous measurements of PM10 showed a good correlation (correlation coefficient: r = 0.93); however, PM levels near the roadside at the intersections were higher than the concentrations at the monitoring station. The relationship between ambient PM level and actual personal exposures was examined. Correlation coefficients between the general ambient outdoors and personal exposure levels were 0.92 for both PM2.5 and PM10. Bangkok air quality data for 1997-2000, including 24-hr average PM10, NO2, SO2, and O3 from eight PCD monitoring stations, were analyzed and validated. The annual arithmetic mean PM10 of the PCD data at the roadside monitoring stations for the last 3 years decreased from 130 to 73 microg/m3, whereas the corresponding levels at the general monitoring stations decreased from 90 to 49 microg/m3. The proportion of days when the level of the 24-hr average PM10 exceeded the NAAQS was between 13 and 26% at roadside stations. PCD data showed PM10 was well correlated with NO2 but not with SO2, suggesting that automobile exhaust is the main source of the particulate air pollution. The results obtained from the simultaneous measurement of PM2.5 and PM10 indicate the potential environmental health hazard of fine particles. In conclusion, Bangkok traffic police were exposed to high levels of automobile-derived particulate air pollution.

Air Pollutants↗
PubMed2005

Influence of air pollution on the incidence of respiratory tract neoplasm.

To evaluate the possible influence of air pollutants on the incidence of respiratory tract neoplasm we studied 12 São Paulo City districts where air pollution is observed. We collected data on pollutants from 1981-1990 and correlated it with the incidence of larynx and lung neoplasms in 1997. Ozone was the pollutant that best correlated with the incidence of neoplasm. The correlation coefficients were 0.7234 (p=0.277) and 0.9929 (p=0.007) for lung and larynx cancer, respectively. There may be a relationship between air pollution and the incidence of respiratory tract neoplasm. This study, however, does not allow us to conclude that there is a causal relationship.

Adolescent↗
PubMed2005

Pollution prevention and control procedure case study: an application for petroleum refineries.

There is global environmental concern about the pollution from industries and other organizations that should not only be controlled but also prevented. Many alternatives are available to those in charge of environmental protection, but they should be able to draw on a systematic procedure to help implement prevention and control measures. At present, there are three immediate tasks: defining the objective of any environmental study, identifying the potential pollution sources, and selecting alternatives to these sources. However, it is necessary to evaluate these alternatives by using as large a number of criteria as possible and making them cumulative so as to enable the classification and selection of the best available techniques for each pollution source. The petroleum refining industry plays an important role in the developed economies and also has a potential for pollution generation that must be controlled. The best solution for all (i.e., petroleum companies, the public, and the environment) is pollution prevention, because this option will protect all of them and will also reduce costs in terms of lower raw materials consumption as well as reducing potential fines. The procedure we have presented in this article has been applied successfully.

Chemical Industry↗
PubMed2005

Interpolating precipitation and its relation to runoff and non-point source pollution.

When rainfall spatially varies, complete rainfall data for each region with different rainfall characteristics are very important. Numerous interpolation methods have been developed for estimating unknown spatial characteristics. However, no interpolation method is suitable for all circumstances. In this study, several methods, including the arithmetic average method, the Thiessen Polygons method, the traditional inverse distance method, and the modified inverse distance method, were used to interpolate precipitation. The modified inverse distance method considers not only horizontal distances but also differences between the elevations of the region with no rainfall records and of its surrounding rainfall stations. The results show that when the spatial variation of rainfall is strong, choosing a suitable interpolation method is very important. If the rainfall is uniform, the precipitation estimated using any interpolation method would be quite close to the actual precipitation. When rainfall is heavy in locations with high elevation, the rainfall changes with the elevation. In this situation, the modified inverse distance method is much more effective than any other method discussed herein for estimating the rainfall input for WinVAST to estimate runoff and non-point source pollution (NPSP). When the spatial variation of rainfall is random, regardless of the interpolation method used to yield rainfall input, the estimation errors of runoff and NPSP are large. Moreover, the relationship between the relative error of the predicted runoff and predicted pollutant loading of SS is high. However, the pollutant concentration is affected by both runoff and pollutant export, so the relationship between the relative error of the predicted runoff and the predicted pollutant concentration of SS may be unstable.

Forecasting↗
PubMed2006

Detoxification and bioremediation potential of a Pseudomonas fluorescens isolate against the major Indian water pollutants.

A Pseudomonas fluorescens strain was isolated from the soil of industrial estate of Aligarh, India. This strain was resistant to some of the major Indian water pollutants, namely Cd2+, Cr6+, Cu2+, Ni2+, Pb2+, BHC, 2,4-D, mancozeb and phenols up to the levels occurring in the highly polluted regions. Moreover, the test strain seems to have a great potential for the detoxification of these pollutants. The decrease in toxicity as determined by the Allium cepa test was recorded as 62.5% for the model water containing the mixture of test heavy metals, 71.9% for the pesticides, 73.2% for phenols, and 58.5% for combination of all these toxicants. These values were obtained after 24 hours, exposure to the immobilized cells of the test isolate in the calcium alginate matrix at the concentrations of these polutants supposedly present in the highly polluted water systems in India. The efficiency of bioremediation for certain heavy metals at the same concentrations by means of immobilized cells of the test Pseudomonas fluorescens isolate was estimated to be 75.9% for cadmium, 74.2% for hexavalent chromium and 61.0% for lead during the 24 hours' treatment. In view of the preliminary work, the test isolate seems to be a good candidate for the bioremediation of water pollutants.

Biodegradation, Environmental↗
PubMed2003

Effects of air pollution on birth weight among children born between 1995 and 1997 in Kaohsiung, Taiwan.

Recent studies have suggested that exposure to air pollution might be associated with low birth weight. The effects of sulfur dioxide (SO(2)) and particulate matter less than 10 microm (PM(10)) were examined on birth weight in each trimester of pregnancy. The study group included all full-term singleton live births during 1995-1997 to women living within about 2 km of an air pollution monitoring site in Kaohsiung. Measurements of SO(2) and PM(10) collected at six air quality monitoring stations were used to estimate the influence of exposures on different pregnancy trimesters. This was done by averaging daily ambient air pollution concentrations during the corresponding days based on the birth date and gestational age of each child. Multiple linear regression analysis was used to estimate the effects of air pollution on birth weight adjusting for possible confounders including maternal age, season, marital status, maternal education, and infant gender. The estimated reduction in birth weight was 0.52 g for 1 microg/m (3) increase in either SO(2) or PM(10) in the first trimester of pregnancy. Data provide further support for the hypothesis that air pollution can affect the outcome of pregnancy.

Adult↗
PubMedDate not supplied

Impact of particulate air pollution on quality-adjusted life expectancy in Canada.

Air pollution and premature death are important public health concerns. Analyses have repeatedly demonstrated that airborne particles are associated with increased mortality and estimates have been used to forecast the impact on life expectancy. In this analysis, we draw upon data from the American Cancer Society (ACS) cohort and literature on utility-based measures of quality of life in relation to health status to more fully quantify the effects of air pollution on mortality in terms of quality-adjusted life expectancy. The analysis was conducted within a decision analytic model using Monte Carlo simulation techniques. Outcomes were estimated based on projections of the Canadian population. A one-unit reduction in sulfate air pollution would yield a mean annual increase in Quality-Adjusted Life Years (QALYs) of 20,960, with gains being greater for individuals with lower educational status and for males compared to females. This suggests that the impact of reductions in sulfate air pollution on quality-adjusted life expectancy is substantial. Interpretation of the results is unclear. However, the potential gains in QALYs from reduced air pollutants can be contrasted to the costs of policies to bring about such reductions. Based on a tentative threshold for the value of health benefits, analysis suggests that an investment in Canada of over 1 billion dollars per annum would be an efficient use of resources if it could be demonstrated that this would reduce sulfate concentrations in ambient air by 1 microg/m(3). Further analysis can assess the efficiency of targeting such initiatives to communities that are most likely to benefit.

Adolescent↗