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Inhomogeneity in response to air pollution in European children (PEACE project).

OBJECTIVES: The PEACE study is a multicentre panel study of the acute effects of particles with a 50% cut off aerodynamic diameter of 10 microns (PM10), black smoke (BS), sulphur dioxide (SO2), and nitrogen dioxide (NO2) on respiratory health of children with chronic respiratory symptoms. In the complete panels no consistent association between air pollution and respiratory health was found. The study evaluated whether potentially more sensitive subgroups in the panels did show effects of air pollution. METHODS: To evaluate heterogeneity in response to air pollution, effect estimates of air pollution on peak expiratory flow (PEF) and respiratory symptoms were calculated in subgroups based on presence of chronic respiratory symptoms, use of respiratory medication, atopy, sex, and baseline lung function. RESULTS: The association between PEF and air pollution was positive in asthmatic children who used respiratory medication whereas the associations tended to be negative in children who did not use respiratory medication selected only on cough. No consistent association was found among asthmatic children who did not use medication. The association between daily prevalence of symptoms and concentrations of air pollution was not different between these subgroups. CONCLUSION: None of the predefined potentially more sensitive subgroups showed a consistent association between air pollution, PEF, and respiratory symptoms.

Air Pollutants↗

Short-term associations between outdoor air pollution and mortality in London 1992-4.

OBJECTIVES: A previous study of the short term effects of air pollution in London from April 1987 to March 1992 found associations between all cause mortality and black smoke and ozone, but no clear evidence of specificity for cardiorespiratory deaths. London data from 1992 to 1994 were analysed to examine the consistency of results over time and to include particles with a mean aerodynamic diameter of 10 microns (PM10) and carbon monoxide. METHODS: Poisson regression was used of daily mortality counts grouped by age and diagnosis, adjusting for trend, seasonality, calendar effects, deaths from influenza, meteorology, and serial correlation. The pollutants examined were particles (PM10 and black smoke), nitrogen dioxide, ozone, sulphur dioxide, and carbon monoxide with single and cumulative lags up to 3 days. RESULTS: No significant associations were found between any pollutant and all cause mortality, but, with the exception of ozone, all estimates were positive. Each pollutant apart from ozone was significantly associated with respiratory mortality; PM10 showed the largest effect (4% increase in deaths of all ages for a 10th-90th percentile increment). The pollutants significantly associated with cardiovascular deaths were nitrogen dioxide, ozone, and black smoke but there was no evidence of an association with PM10. In two pollutant models of respiratory deaths, the effect of black smoke, which in London indicates fine particles of diesel origin, was independent of that of PM10, but not vice versa. CONCLUSION: These results from a new data set confirm a previous report that there are associations between various air pollutants and daily mortality in London. This new study found greater specificity for associations with respiratory and cardiovascular deaths, and this increases the plausibility of a causal explanation. However, the effects of ozone found in the earlier study were not replicated. The fraction of PM10 which comprises black smoke accounted for much of the effect of PM10.

Adolescent↗

Investigation of factors which might indicate susceptibility to particulate air pollution.

OBJECTIVES: To determine whether previous symptoms or recognized risk factors of cardiovascular ill health, are associated with an increased likelihood of adverse health effects related to particulate air pollution. METHODS: Cardiovascular event rates were studied relative to urban concentrations of particulate air pollution and baseline risk factors. The Edinburgh artery study consisted of a cohort of 1592 subjects aged 55-74 and was followed up to the end of March 1998 for a median of 10 years resulting in about 5 million person-days of observation. Baseline measurements included plasma fibrinogen and blood and plasma viscosity. A nested case-control approach was used to investigate a possible interaction between effects of these selected baseline risk factors and particulate air pollution, on subsequent event rates. RESULTS: During the follow up period there were 343 fatal and non-fatal myocardial infarctions or strokes. Trends in adverse cardiovascular outcomes related to pollution were identified among subjects belonging to the highest baseline quintile of plasma fibrinogen. Evidence for interactions between concentrations of particulate pollution and fibrinogen was not established at conventional levels of significance. CONCLUSIONS: People with high concentrations of plasma fibrinogen might be more susceptible to adverse cardiovascular effects of particulate air pollution, but limitations of power mean that evidence relating to such an interaction is not conclusive. A range of cardiopulmonary risk factors warrant investigation in relation to possible susceptibility to air pollution.

Aged↗

Acute effects of winter air pollution on respiratory function in schoolchildren in southern England.

AIM: To investigate the acute health effects of winter outdoor air pollution (nitrogen dioxide (NO(2)), ozone (O(3)), sulphur dioxide (SO(2)), sulphate (SO(4)(2-)),and particles (PM(10))) on schoolchildren in an area of southern England where levels of SO(2) had been reported to be high. METHODS: A total of 179 children, aged 7-13, from three schools (two urban and one rural location), were included. Peak expiratory flow rate (PEFR) and presence or absence of upper respiratory infections were recorded on 63 school days from 1 November 1996 to 14 February 1997. Air pollution and meteorological data were taken from monitors at each school site. The analysis regressed daily PEFR on pollutant level adjusting for confounders and serial correlation and calculated a weighted pooled estimate of effect overall for each pollutant. In addition, large decrements in PEFR were analysed as a binary outcome. Same day, lag 1, lag 2, and a five day average of pollutant levels were used. RESULTS: There were no clear effects of any pollutant on mean PEFR. In addition, we analysed large PEFR decrements (a binary outcome), observing consistent negative associations with NO(2), SO(4)(2-), and PM(10), although few lag/pollutant combinations were significant: odds ratios (95% CI) for five day average effect: NO(2) 24 h average 1.043 (1.000 to 1.089), SO(4)(2-) 1.090 (0.898 to 1.322), PM(10) 1.037 (0.992 to 1.084). The observed effects of PM(10) (only) were stronger in wheezy children (1.114 (1.057 to 1.174)). There were no consistent negative associations between large decrements and ozone or SO(2). CONCLUSIONS: There is no strong evidence for acute effects of winter outdoor air pollution on mean PEFR overall in this area, but there is evidence for negative effects on large PEFR decrements.

Adolescent↗

The effect of air pollution on inner-city children with asthma.

The effect of daily ambient air pollution was examined within a cohort of 846 asthmatic children residing in eight urban areas of the USA, using data from the National Cooperative Inner-City Asthma Study. Daily air pollution concentrations were extracted from the Aerometric Information Retrieval System database from the Environment Protection Agency in the USA. Mixed linear models and generalized estimating equation models were used to evaluate the effects of several air pollutants (ozone, sulphur dioxide (SO2), nitrogen dioxide (NO2) and particles with a 50% cut-off aerodynamic diameter of 10 microm (PM10) on peak expiratory flow rate (PEFR) and symptoms in 846 children with a history of asthma (ages 4-9 yrs). None of the pollutants were associated with evening PEFR or symptom reports. Only ozone was associated with declines in morning % PEFR (0.59% decline (95% confidence interval (CI) 0.13-1.05%) per interquartile range (IQR) increase in 5-day average ozone). In single pollutant models, each pollutant was associated with an increased incidence of morning symptoms: (odds ratio (OR)=1.16 (95% CI 1.02-1.30) per IQR increase in 4-day average ozone, OR=1.32 (95% CI 1.03-1.70) per IQR increase in 2-day average SO2, OR=1.48 (95% CI 1.02-2.16) per IQR increase in 6-day average NO2 and OR=1.26 (95% CI 1.0-1.59) per IQR increase in 2-day average PM10. This longitudinal analysis supports previous time-series findings that at levels below current USA air-quality standards, summer-air pollution is significantly related to symptoms and decreased pulmonary function among children with asthma.

Air Pollutants↗

Association of air pollution with increased incidence of ventricular tachyarrhythmias recorded by implanted cardioverter defibrillators.

Epidemiologic studies have demonstrated a consistent link between sudden cardiac deaths and particulate air pollution. We used implanted cardioverter defibrillator (ICD) records of ventricular tachyarrhythmias to assess the role of air pollution as a trigger of these potentially life-threatening events. The study cohort consisted of 203 cardiac patients with ICD devices in the Boston metropolitan area who were followed for an average of 3.1 years between 1995 and 2002. Fine particle mass and gaseous air pollution plus temperature and relative humidity were measured on almost all days, and black carbon, sulfate, and particle number on a subset of days. Date, time, and intracardiac electrograms of ICD-detected arrhythmias were downloaded at the patients' regular follow-up visits (about every 3 months). Ventricular tachyarrhythmias were identified by electrophysiologist review. Risk of ventricular arrhythmias associated with air pollution was estimated with logistic regression, adjusting for season, temperature, relative humidity, day of the week, patient, and a recent prior arrhythmia. We found increased risks of ventricular arrhythmias associated with 2-day mean exposure for all air pollutants considered, although these associations were not statistically significant. We found statistically significant associations between air pollution and ventricular arrhythmias for episodes within 3 days of a previous arrhythmia. The associations of ventricular tachyarrhythmias with fine particle mass, carbon monoxide, nitrogen dioxide, and black carbon suggest a link with motor vehicle pollutants. The associations with sulfate suggest a link with stationary fossil fuel combustion sources.

Adult↗

Lung cancer and air pollution.

Epidemiologic studies over the last 40 years suggest rather consistently that general ambient air pollution, chiefly due to the incomplete combustion of fossil fuels, may be responsible for increased rates of lung cancer. This evidence derives from studies of lung cancer trends, studies of occupational groups, comparisons of urban and rural populations, and case-control and cohort studies using diverse exposure metrics. Recent prospective cohort studies observed 30 to 50% increases in lung cancer rates associated with exposure to respirable particles. While these data reflect the effects of exposures in past decades, and despite some progress in reducing air pollution, large numbers of people in the United States continue to be exposed to pollutant mixtures containing known or suspected carcinogens. It is not known how many people in the United States are exposed to levels of fine respirable particles that have been associated with lung cancer in recent epidemiologic studies. These observations suggest that the most widely cited estimates of the proportional contribution of air pollution to lung cancer occurrence in the United States based largely on the results of animal studies, may be too low. It is important that better epidemiologic research be conducted to allow improved estimates of lung cancer risk from air pollution among the general population. The development and application of new epidemiologic methods, particularly the improved characterization of population-wide exposure to mixtures of air pollutants and the improved design of ecologic studies, could improve our ability to measure accurately the magnitude of excess cancer associated with air pollution.

Air Pollutants↗

Ambient air pollution as a risk factor for lung cancer.

Epidemiologic studies over the last 40 years have observed that general ambient air pollution, chiefly due to the by-products of the incomplete combustion of fossil fuels, is associated with small relative increases in lung cancer. The evidence derives from studies of lung cancer trends, studies of occupational groups, comparisons of urban and rural populations, and case-control and cohort studies using diverse exposure metrics. Recent prospective cohort studies observed 30-50% increases in the risk of lung cancer in relation to approximately a doubling of respirable particle exposure. While these data reflect the effects of exposures in past decades, and despite some progress in reducing air pollution, large numbers of people in the US continue to be exposed to pollutant mixtures containing known or suspected carcinogens. These observations suggest that the most widely cited estimates of the proportional contribution of air pollution to lung cancer occurrence in the US, based largely on the results of animal experimentation, may be too low. It is important that better epidemiologic research be conducted to allow improved estimates of lung cancer risk from air pollution in the general population. The development and application of new epidemiologic methods, particularly the improved characterization of population-wide exposure to mixtures of air pollutants and the improved design of ecologic studies, could improve our ability to measure accurately the magnitude of excess cancer related to air pollution.

Air Pollutants↗

Modeling pollutant release from a surface source during rainfall runoff.

Though runoff from manure spread fields is recognized as an important mode of nonpoint-source pollution, there are no models that mechanistically describe transport from a field-spread manure-type source. A mechanistic, physically based model for pollutant release from a surface source, such as field-spread manure, was hypothesized, laboratory tested, and field-applied. The primary objective of this study was to demonstrate the potential applicability of a mechanistic model to pollutant release from surface sources. The laboratory investigation used stable sources and a conservative "pollutant" (KCl) so that the dynamic effects of source dissolution and chemical transformations could be ignored and transport processes isolated. The field investigation used runoff and soluble reactive phosphorus (SP) data collected from a dairy-manure-spread field in the Cannonsville watershed in the Catskills region of New York State. The model predictions corroborated well with observations of runoff and pollutant delivery in both the laboratory and the field. "Pollutant" release from surface sources was generally predicted within 11% of laboratory KCl measurements and field SP observations. Laboratory flume runoff predictions with 15 and 26% errors for 25 and 15 mm h(-1) simulated rainfall intensity experiments, respectively, represented root mean square errors of less than 0.2 mLs(-1). A 26% error was calculated for overland flow predictions in the field, which translated into approximately a 39 mLs(-1) error. Results suggest that the hypothesized model satisfactorily represents the primary mechanisms in pollutant release from surface sources.

Agriculture↗

[A review of original papers that analyze the effects of air pollution on mortality, 1994-1998].

The different studies published and indexed in Medline and in the Spanish Medical Index (IME) from 1984 up to 1998 (IME: 1971-1996) are reviewed. To start with, an assessment was made of the number of publications put out which have to do with the impact of pollution on human health as well as the percentage thereof which analyze the mortality as a health indicator. Afterward, the original works published within the January 1994-June 1998 period were reviewed in detail. Most of the original articles are combined time series studies which analyze, on a single-day basis, the relationship between the levels of pollution and the mortality for non-accidental causes. Other original articles were also summarized based on an approach other than the time series one, highlighting different cohort studies which relate the levels of pollution to the mortality on an individual level and which confirm the findings of prior ecological studies. The pollutants analyzed most often are the different types of particles, although studies are also common regarding the impact of sulfur dioxide, nitrogen dioxide, ozone and carbon monoxide. The method of analysis most used is the Poisson regression, into which different confusion variables bearing an impact thereon such as seasonality and tendency, temperature and relative humidity and day of the year are basically added. In the studies reviewed, the positive significant findings prevail, being consistent especially for particles, which is the pollutant most analyzed. The articles studying other pollutants, although fewer in number, also indicate a significant relationship between pollution levels and the mortality.

Air Pollutants↗

Air pollution and health.

OBJECTIVE: To review the effects of air pollution on health, with special reference to data obtained locally in Hong Kong. DATA SOURCES: Medline literature search (1960-1999), websites of the World Health Organization and Environmental Protection Department, Hong Kong, and a report from the Sub-Working Group on the Review of Hong Kong's Air Quality Objectives, 1999. STUDY SELECTION: Key words for the literature search were 'air pollution' and 'health'. DATA EXTRACTION: The author reviewed relevant information and data. DATA SYNTHESIS: In many parts of the world and in Hong Kong, air pollution is associated with increased mortality and morbidity rates, as reflected by increased hospital admissions and doctor visits, not only for respiratory illnesses but also for cardiovascular illnesses. Some studies have found that air pollution is also associated with an increase in respiratory symptoms in lower lung function in children. In Hong Kong, air pollution is mostly because of traffic emissions. During the past decade, the annual mean levels of respirable suspended particulates and oxides of nitrogen and ozone have increased and exceeded the air quality objectives set by the Environmental Protection Department of Hong Kong. CONCLUSION: The medical profession should be concerned about the health effects of air pollution and should call for action to reduce the current levels of air pollution to an acceptable level.

Air Pollutants↗

[New advances in research of combined pollution].

Combined pollution has become one of the important directions of environmental science at present. In this paper, new advances of studies on combined pollution were summarized. The studies of inorganic combined pollution, inorganic-organic combined pollution and organic combined pollution were reviewed. The mechanisms of combined pollution were approached from chemistry, physiology, enzymology, cytology and molecular biology. Then some problems and developing aspects on the research of combined pollution were put forward.

Environmental Pollutants↗

Air pollution and children's health.

Children's exposure to air pollution is a special concern because their immune system and lungs are not fully developed when exposure begins, raising the possibility of different responses than seen in adults. In addition, children spend more time outside, where the concentrations of pollution from traffic, powerplants, and other combustion sources are generally higher. Although air pollution has long been thought to exacerbate minor acute illnesses, recent studies have suggested that air pollution, particularly traffic-related pollution, is associated with infant mortality and the development of asthma and atopy. Other studies have associated particulate air pollution with acute bronchitis in children and demonstrated that rates of bronchitis and chronic cough declined in areas where particle concentrations have fallen. More mixed results have been reported for lung function. Overall, evidence for effects of air pollution on children have been growing, and effects are seen at concentrations that are common today. Although many of these associations seem likely to be causal, others require and warrant additional investigation.

Air Pollutants↗

[Health effects of outdoor air pollution].

BACKGROUND: This paper addresses the contribution from epidemiological research to our current understanding of the health effects of ambient air pollution. MATERIAL AND METHODS: Well-known examples from the international literature are presented in order to describe the most commonly used research designs and show how such studies have contributed to our knowledge. A review of Norwegian studies is presented. RESULTS: A large number of studies have shown that quite low levels of air pollution are associated with negative health effects. Most studies have assessed short-term effects and both respiratory and cardiovascular effects have been shown to be associated with exposure to air pollutants. INTERPRETATION: The general view is that particulate matter causes the adverse health effect of air pollution, even though epidemiological studies alone have obvious limitations when it comes to conclusions about causation. Few Norwegian air pollution studies have so far been carried out; estimates of the health effects of air pollution in Norway must mainly rely on studies carried out in places with different climate and air pollution composition.

Air Pollutants↗

[Zoning planning in non-point source pollution control in Hanyang district].

It is most important for managing urban non-point source (NPS) pollution, actualizing the urban sustainable development as well, that zoning planning of urban NPS pollution control is studied. A case study on principles and methods of zoning planning in urban NPS pollution is carried out. Principles of urban sustainable development, priority of urban NPS pollution sensitivity, similarity of urban NPS control direction and region conjugate are put forward. Besides, it is for the first time that a more quantitive method is presented, in the case of Hanyang district, Wuhan city, which is based on L-THIA model and spatial analysis technique in GIS. Assessment of NPS pollution status quo, as well as analysis of NPS sensitivity, is the kernel component of the quantitive method. Hanyang might be divided into four NPS pollution control zones. It is helpful for decision-making of regional NPS pollution control.

China↗

Role of bougainvilleas in mitigation of environmental pollution.

Environmental pollution adversely affects health of the people. Industrialization, urbanization, over exploitation of natural resources and increasing number of automobiles have aggravated the pollution manifold though there are various ways to mitigate the environmental pollution. Bio-remediation by using selected plant species is an effective method to control pollution which is universally accepted. Bougainvillea is a pollution tolerant plant and can help in the mitigation of air pollution besides its ornamental value in the landscaping. From the rich germplasm collection in NBRI Botanical Garden, tolerant plants have been experimented for road side plantation in view of mitigating the environmental pollution.

Air Pollutants↗

[Current data on atmospheric pollutions].

Atmospheric pollutions (AP) are very important for human health and ecological equilibrium. They may be natural or anthropogenic and in this later case they can appear outdoor or indoor. Urban air pollution is the most known form of AP. Its main sources are industries, individual and collective heating and now mainly automobile traffic in most cities. Classical AP indicators are SO2, particles, NOx, CO and Pb measured in networks. Important factors of AP are amounts of pollutants emitted and local climatic and meteorological characteristics. Health effects of AP peaks and of AP background levels are not well known. But generally, mean AP levels of SO2 and particles decreased in the last years in most towns as the consequence of collective actions on the three main sources of AP and on fuels, emission and immission levels; but more is wanted about motor-cars. Progress are necessary for limitation of three major ecological risks: "acid-rain" (SO2 and NOx derivatives, ozone,...) which participates in lake and forest attacks; "green house" effects whose air CO2 concentration increase is the main responsible, and stratospheric ozone depletion mainly due to freons (CFC); the consequences of these two last phenomena are not well known but ecological and health risk exist. Besides, indoor air pollution (IAP) is very important because we live more than 20 h a day indoor. IAP may be occupational (a lot of chemical or biological agents) or not. In the later case air pollutants are very various: CO, NOx and particles from heating or cooking, formaldehyde from wood glue, plywood or urea-formol foams, radon and derivatives in some granitic countries, odd jobs products, cosmetics, aero-allergens of chemical or biological origins, microbes,... Environmental tobacco smoke (ETS) is also an important pollutant complex. Risks of IAP are real or potential: acute risk is obvious for CO, aero-allergens, formaldehyde, NOx,...); irritations are produced by ETS, formaldehyde, solvants,...; long term or potential risks are of concern for asbest, radon,... A complex and bad known pathology is described in a lot of modern buildings as the "Sick Building Syndrom". Indoor air quality is very dependant of the quality of ventilation and possible air treatment. It may be considered in all urban epidemiological studies about air pollution.

Air Pollution↗

[Pollution with sulfur dioxide in an inhabited industrial area. Methodologic problems in monitoring].

The area around Rho and Pero in the north west of the province of Milan is densely populated and highly industrialised. It is also characterised by high levels of sulphur dioxide pollution. During the 1980s it was decided to check the sources of production of the pollutant and its distribution in the area. The main area for improvement was the refinery at Rho where it was aimed to disperse gases at a higher level by raising the chimneys and to use fuel gas in those burners which were connected to lower chimneys. For domestic systems it was decided to diffuse the use of methane as much as possible and limit oil-fired central heating, by statute from the Mayor. In order to rationalise the programme of action the pollution was to be determined for each single area by subdivision of the territory into a grid. By means of a census of all the production sources of sulphur dioxide appropriate data were collected to estimate each area's contribution to pollution. The theoretical hourly quantity of sulphur dioxide was calculated on the basis of the combustion equation. The data were then analysed, in total and divided into component parts, i.e. the type of fuel used, the season of the year and industrial or domestic usage. With Gifford and Hanna's ATDL mathematical model the data thus obtained, together with meteorological variables, were used to simulate the expected effect on the distribution of pollution after carrying out the programmed actions. The simulations foresee a reduction of up to 80% of sulphur dioxide concentrations in the areas of greatest use of liquid fuels. In the territory in question the monitoring of the pollutant was assured by the presence of five fixed positions of continuous survey. These turned out to be useful above all for analysis of the phenomenon over a period of time. In order to study spatial distribution better 374 findings were gathered in the winter of 1985-6 from various points of the territory by means of a mobile instantaneous detector. From these data the average aerial concentration was calculated on a grid, with sides of 500 metres, first for all the observations and then separately for the direction of the wind. Taking into account meteorological factors and the actual hour (during daytime) when the concentration of the pollutant was recorded, it was possible to estimate concentrations by means of linear models in which meteorological parameters were taken as independent variables.(ABSTRACT TRUNCATED AT 400 WORDS)

Air Pollutants↗