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PubMed2004

Simulating urban-scale air pollutants and their predicting capabilities over the Seoul metropolitan area.

Urban-scale air pollutants for sulfur dioxide, nitrogen dioxide, particulate matter with aerodynamic diameter > or = 10 microm, and ozone (O3) were simulated over the Seoul metropolitan area, Korea, during the period of July 2-11, 2002, and their predicting capabilities were discussed. The Air Pollution Model (TAPM) and the highly disaggregated anthropogenic and the biogenic gridded emissions (1 km x 1 km) recently prepared by the Korean Ministry of Environment were applied. Wind fields with observational nudging in the prognostic meteorological model TAPM are optionally adopted to comparatively examine the meteorological impact on the prediction capabilities of urban-scale air pollutants. The result shows that the simulated concentrations of secondary air pollutant largely agree with observed levels with an index of agreement (IOA) of >0.6, whereas IOAs of approximately 0.4 are found for most primary pollutants in the major cities, reflecting the quality of emission data in the urban area. The observationally nudged wind fields with higher IOAs have little effect on the prediction for both primary and secondary air pollutants, implying that the detailed wind field does not consistently improve the urban air pollution model performance if emissions are not well specified. However, the robust highest concentrations are better described toward observations by imposing observational nudging, suggesting the importance of wind fields for the predictions of extreme concentrations such as robust highest concentrations, maximum levels, and >90th percentiles of concentrations for both primary and secondary urban-scale air pollutants.

Air↗

PubMed1995

Assessment of the future impact on health of a proposed freeway development.

This paper estimates the effect on health of traffic injury and air and noise pollution from a proposed inner-suburban freeway in Melbourne. We estimated levels of these health problems for the year 2001 using traffic flow projections for the presence and absence of the freeway. For noise and air pollution, it was necessary to use pollutant levels as proxies for levels of associated diseases and health states. In 2001, there will be an increase in all traffic movements in the study area but a decrease of 100,000 vehicle-kilometers per day on major roads, excluding the bypass. This is associated with a projected reduction in the study area of about 100 to 110 injuries of all types. The major air pollution problems associated with motor vehicle emissions are ozone and respirable particulates; sulphur dioxide, nitrogen dioxide and carbon monoxide are unlikely to pose a health hazard. Levels of respirable particulates, lead and polycylic aromatic hydrocarbons are generally low. There should be no detectable increase in average or maximum noise levels adjacent to the freeway if attenuation measures are employed. A reduction in average and maximum noise levels should occur on some main roads in the affected area. The effects of the freeway on the area should be favourable to health, with reduction in traffic injury and noise-related health problems outweighing any risk of a small deterioration in respiratory health associated with atmospheric pollution.

Accidents, Traffic↗

PubMed2004

Association between ambient air pollution and birth weight in São Paulo, Brazil.

OBJECTIVES: Previous studies have implicated air pollution in increased mortality and morbidity, especially in the elderly population and children. More recently, associations with mortality in infants and with some reproductive outcomes have also been reported. The aim of this study is to explore the association between exposure to outdoor air pollution during pregnancy and birth weight. DESIGN: Cross sectional study using data on all singleton full term live births during a one year period. For each individual birth, information on gestational age, type of delivery, birth weight, sex, maternal education, maternal age, place of residence, and parity was available. Daily mean levels of PM(10), sulphur dioxide, nitrogen dioxide, carbon monoxide, and ozone were also gathered. The association between birth weight and air pollution was assessed in regression models with exposure averaged over each trimester of pregnancy. SETTING: São Paulo city, Brazil. RESULTS: Birth weight was shown to be associated with length of gestation, maternal age and instruction, infant gender, number of antenatal care visits, parity, and type of delivery. On adjusting for these variables negative effects of exposure to PM(10) and carbon monoxide during the first trimester were observed. This effect seemed to be more robust for carbon monoxide. For a 1 ppm increase in mean exposure to carbon monoxide during the first trimester a reduction of 23 g in birth weight was estimated. CONCLUSIONS: The results are consistent in revealing that exposure to air pollution during pregnancy may interfere with weight gain in the fetus. Given the poorer outlook for low birthweight babies on a number of health outcomes, this finding is important from the public health perspective.

Adult↗

PubMed2003

Air pollution and case fatality of SARS in the People's Republic of China: an ecologic study.

BACKGROUND: Severe acute respiratory syndrome (SARS) has claimed 349 lives with 5,327 probable cases reported in mainland China since November 2002. SARS case fatality has varied across geographical areas, which might be partially explained by air pollution level. METHODS: Publicly accessible data on SARS morbidity and mortality were utilized in the data analysis. Air pollution was evaluated by air pollution index (API) derived from the concentrations of particulate matter, sulfur dioxide, nitrogen dioxide, carbon monoxide and ground-level ozone. Ecologic analysis was conducted to explore the association and correlation between air pollution and SARS case fatality via model fitting. Partially ecologic studies were performed to assess the effects of long-term and short-term exposures on the risk of dying from SARS. RESULTS: Ecologic analysis conducted among 5 regions with 100 or more SARS cases showed that case fatality rate increased with the increment of API (case fatality = - 0.063 + 0.001 * API). Partially ecologic study based on short-term exposure demonstrated that SARS patients from regions with moderate APIs had an 84% increased risk of dying from SARS compared to those from regions with low APIs (RR = 1.84, 95% CI: 1.41-2.40). Similarly, SARS patients from regions with high APIs were twice as likely to die from SARS compared to those from regions with low APIs. (RR = 2.18, 95% CI: 1.31-3.65). Partially ecologic analysis based on long-term exposure to ambient air pollution showed the similar association. CONCLUSION: Our studies demonstrated a positive association between air pollution and SARS case fatality in Chinese population by utilizing publicly accessible data on SARS statistics and air pollution indices. Although ecologic fallacy and uncontrolled confounding effect might have biased the results, the possibility of a detrimental effect of air pollution on the prognosis of SARS patients deserves further investigation.

Air Pollutants↗

PubMed2000

Air pollution and daily mortality in three U.S. counties.

I used generalized additive models to analyze the time-series of daily total nonaccidental and cause-specific (cardiovascular, cerebrovascular, and chronic obstructive pulmonary disease) deaths over the period 1987-1995 in three major U.S. metropolitan areas: Cook County, Los Angeles County, and Maricopa County. In all three counties I had monitoring information on particulate matter [less than/equal to] 10 microm (PM(10)), carbon monoxide, sulfur dioxide, nitrogen dioxide, and ozone. In Los Angeles, monitoring information on particulate matter [less than/equal to] 2.5 microm (PM(2.5)) was available as well. I present the results of both single and multi-pollutant analyses. Air pollution was associated with each of the mortality end points. With respect to the individual components of the pollution mix, the results indicate considerable heterogeneity of air pollution effects in the different geographic locations. In general, the gases, particularly CO, but not ozone, were much more strongly associated with mortality than was particulate matter. This association was particularly striking in Los Angeles County.

Air Pollutants↗

PubMed2001

Some considerations concerning multimedia-multipollutant risk assessment methodology: use of epidemiologic data for non-cancer risk assessment in Russia.

The highly industrialized small town of Verkhnyaya Pyshma (in the Urals region of Russia) was chosen as the site of a multimedia-multipollutant risk assessment using the U.S. Environmental Protection Agency methodology. The assessment was based on routine environmental pollution monitoring data for ambient air, soils, drinking water, and food, and the international environmental epidemiology literature. Using an a priori set of the preliminary health-based criteria, we selected nine pollutants for risk assessment: total suspended particles (TSP), sulfur dioxide, nitrogen dioxide, benzo(a)pyrene (BaP), ammonia arsenic, copper, cadmium, and lead. We used dose-response functions derived from epidemiologic studies to assess individual and population risks for TSP, SO2, NO2, As, Cd, and Pb. We assessed both cancer (for BaP, As, and Cd) and non-cancer (for all the chosen pollutants but BaP) responses, but in this paper we discuss only the assessments of noncarcinogenic risks due to TSP, SO2, NO2, Pb, and Cd as examples of how the quantitative estimates of health effects can be produced by using a risk function approach. We also schematically present a modified conceptual model of multimedia-multipollutant risk assessment taking into account the experience gained with this study.

Adolescent↗

PubMed2005

The association between fatal coronary heart disease and ambient particulate air pollution: Are females at greater risk?

The purpose of this study was to assess the effect of long-term ambient particulate matter (PM) on risk of fatal coronary heart disease (CHD). A cohort of 3,239 nonsmoking, non-Hispanic white adults was followed for 22 years. Monthly concentrations of ambient air pollutants were obtained from monitoring stations [PM < 10 microm in aerodynamic diameter (PM10), ozone, sulfur dioxide, nitrogen dioxide] or airport visibility data [PM < 2.5 microm in aerodynamic diameter (PM2.5)] and interpolated to ZIP code centroids of work and residence locations. All participants had completed a detailed lifestyle questionnaire at baseline (1976), and follow-up information on environmental tobacco smoke and other personal sources of air pollution were available from four subsequent questionnaires from 1977 through 2000. Persons with prevalent CHD, stroke, or diabetes at baseline (1976) were excluded, and analyses were controlled for a number of potential confounders, including lifestyle. In females, the relative risk (RR) for fatal CHD with each 10-microg/m3 increase in PM2.5 was 1.42 [95% confidence interval (CI), 1.06-1.90] in the single-pollutant model and 2.00 (95% CI, 1.51-2.64) in the two-pollutant model with O3. Corresponding RRs for a 10-microg/m3 increase in PM(10-2.5) and PM10 were 1.62 and 1.45, respectively, in all females and 1.85 and 1.52 in postmenopausal females. No associations were found in males. A positive association with fatal CHD was found with all three PM fractions in females but not in males. The risk estimates were strengthened when adjusting for gaseous pollutants, especially O3, and were highest for PM2.5. These findings could have great implications for policy regulations.

Aged↗

PubMed1994

The role of airway mucus in pulmonary toxicology.

Airway mucus is a complex airway secretion whose primary function as part of the mucociliary transport mechanism is to to serve as renewable and transportable barrier against inhaled particulates and toxic agents. The rheologic properties necessary for this function are imparted by glycoproteins, or mucins. Some respiratory disease states, e.g., asthma, cystic fibrosis, and bronchitis, are characterized by quantitative and qualitative changes in mucus biosynthesis that contribute to pulmonary pathology. Similar alterations in various aspects of mucin biochemistry and biophysics, leading to mucus hypersecretion and altered mucus rheology, result from inhalation of certain air pollutants, such as ozone, sulfur dioxide, nitrogen dioxide, and cigarette smoke. The consequences of these pollutant-induced alterations in mucus biology are discussed in the context of pulmonary pathophysiology and toxicology.

Air Pollutants↗

PubMed1996

Association between ozone and asthma emergency department visits in Saint John, New Brunswick, Canada.

This study examines the relationship of asthma emergency department (ED) visits to daily concentrations of ozone and other air pollutants in Saint John, New Brunswick, Canada. Data on ED visits with a presenting complaint of asthma (n = 1987) were abstracted for the period 1984-1992 (May-September). Air pollution variables included ozone, sulfur dioxide, nitrogen dioxide, sulfate, and total suspended particulate (TSP); weather variables included temperature, humidex, dewpoint, and relative humidity. Daily ED visit frequencies were filtered to remove day of the week and long wave trends, and filtered values were regressed on air pollution and weather variables for the same day and the 3 previous days. The mean daily 1-hr maximum ozone concentration during the study period was 41.6 ppb. A positive, statistically significant (p < 0.05) association was observed between ozone and asthma ED visits 2 days later, and the strength of the association was greater in nonlinear models. The frequency of asthma ED visits was 33% higher (95% CI, 10-56%) when the daily 1-hr maximum ozone concentration exceeded 75 ppb (the 95th percentile). The ozone effect was not significantly influenced by the addition of weather or other pollutant variables into the model or by the exclusion of repeat ED visits. However, given the limited number of sampling days for sulfate and TSP, a particulate effect could not be ruled out. We detected a significant association between ozone and asthma ED visits, despite the vast majority of sampling days being below current U.S. and Canadian standards.

Adolescent↗

PubMed1987

Daily air pollution effects on children's respiratory symptoms and peak expiratory flow.

To identify acute respiratory health effects associated with air pollution due to coal combustion, a subgroup of elementary school-aged children was selected from a large cross-sectional study and followed daily for eight months. Children were selected to obtain three equal-sized groups: one without respiratory symptoms, one with symptoms of persistent wheeze, and one with cough or phlegm production but without persistent wheeze. Parents completed a daily diary of symptoms from which illness constellations of upper respiratory illness (URI) and lower respiratory illness (LRI) and the symptom of wheeze were derived. Peak expiratory flow rate (PEFR) was measured daily for nine consecutive weeks during the eight-month study period. Maximum hourly concentrations of sulfur dioxide, nitrogen dioxide, ozone, and coefficient of haze for each 24-hour period, as well as minimum hourly temperature, were correlated with daily URI, LRI, wheeze, and PEFR using multiple regression models adjusting for illness occurrence or level of PEFR on the immediately preceding day. Respiratory illness on the preceding day was the most important predictor of current illness. A drop in temperature was associated with increased URI and LRI but not with increased wheeze or with a decrease in level of PEFR. No air pollutant was strongly associated with respiratory illness or with level of PEFR, either in the group of children as a whole, or in either of the symptomatic subgroups; the pollutant concentrations observed, however, were uniformly lower than current ambient air quality standards. Moreover, since exposure estimation based on monitoring of ambient air likely results in misclassification of the true exposure, the negative findings of this study must be interpreted cautiously.

Air Pollutants↗

PubMed1999

Air pollution and daily mortality in Inchon, Korea.

The association between total daily mortality and air pollution was investigated for a 1-year period (January 1995 to December 1995) in Inchon, Korea. The purpose of this study was to evaluate the relative importance of particulate and gaseous air pollution as predictors of daily mortality. Concentration of total suspended particulates (TSP), inhalable particles (PM10), and gaseous pollutants, such as sulfur dioxide, nitrogen dioxide, ozone, carbon monoxide, were measured daily during the study period. A generalized additive model was used to regress daily death counts on each air pollutant, controlling for time trend and meteorologic influences such as temperature or relative humidity. Total mortality was found to increase 1.2% (95% CI: 0.2 to 2.2%) for each 10 microg/m3 increase in 6-day moving average of TSP, and 1.2% (95% CI 0.2 to 2.1%) for each 10 microg/m3 increase in 5-day moving average of PM10. The association is similar in magnitude to associations between particulate air pollution and mortality found in several other communities in America and Europe. Associations with gaseous pollutants were all statistically insignificant in the generalized additive model. The relative risk of death increased at particulate levels that were well below the current Korean Ambient Air Quality Standard.

Air Pollutants↗

PubMed1991

Ambient air pollution and respiratory disease.

OBJECTIVE: To review the literature on ambient air pollution and respiratory disease, and to consider the criteria for defining causation. DATA SOURCES: Medical and scientific journals indexed by Medline, conferences, proceedings and monographs. STUDY SELECTION: Two kinds of study were selected--(i) controlled clinical trials which have exposed normal or asthmatic subjects and/or patients with chronic obstructive airways disease to sulphur dioxide, nitrogen dioxide or ozone; and (ii) epidemiological studies which have investigated the chronic toxicity of these pollutants, acid aerosols and polycyclic aromatic hydrocarbons. DATA EXTRACTION AND SYNTHESIS: Experimental studies were tabulated under the headings "Design", "Subjects", "Pollutant concentration", "Duration of exposure", "Outcome measures" and "Conclusions". Epidemiological studies were summarised and compared in an attempt to reconcile conflicting results. (The experimental and epidemiological evidence has been used by regulatory bodies to develop ambient air quality guidelines.) CONCLUSIONS: At the present state of knowledge, it is not possible to conclude that air pollution can cause respiratory disease de novo, but levels marginally above current guidelines certainly have adverse effects on individuals with pre-existing chronic lung disease.

Air Pollutants↗

PubMedDate not supplied

[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↗

PubMed2002

Urban air pollution and respiratory allergy.

Evidence suggests that urbanization with its high levels of vehicle emissions, and westernized lifestyle are linked to the rising incidence of pollen-induced respiratory allergy seen in most industrialized countries. Moreover, the increase in respiratory allergy parallels an increase in outdoor and indoor air pollution. Although the role played by outdoor pollutants in allergic sensitization of airways has yet to be elucidated, it is well established that outdoor pollution exacerbates respiratory symptoms in atopic subjects. This review focuses on the evidence implicating outdoor pollution in pollen-related respiratory diseases. Acute and chronic exposure to such components of air pollution as sulphur dioxide, nitrogen dioxide, ozone and respirable particulate matter (isolated or in various combinations) enhances airway responsiveness to aeroallergens in atopic subjects. By attaching to the surface of pollen grains and of plant-derived paucimicronic particles, pollutants can modify the morphology of these antigen-carrying agents and alter their allergenic potential. In addition, by inducing airway inflammation, which increases airway epithelial permeability, pollutants overcome the mucosal barrier and so "prime" allergen-induced responses. Lastly, air pollutants such as diesel exhaust particulates can also facilitate the immunoglobulin (Ig)E response that leads to pollinosis symptoms in atopic individuals.

Air Pollution↗

PubMedDate not supplied

[Mucociliary function and its alteration by certain irritants (author's transl)].

Mucociliary clearance is usually estimated in vivo by the measurement of mucus transfer or by clearance of radio-active tracers previously deposited in the airways. These methods are relatively difficult and complex so that for routine studies measures are usually made of ciliary activity. To clarify the consequences of changes in activity the authors have established the relationship between the speed of mucus transport and the frequency of ciliary beating. From their own studies and from evidence in the literature they show how the clearance function of mucociliary activity can be disturbed by a fall in temperature and humidity, by viral infection, by atmospheric pollutants such as sulphur dioxide, nitrogen dioxide and aldehydes and by tobacco smoking. They indicate the beneficial effects obtained by the administration of beta adrenergic compounds and the limits of efficiency of mucolytic agents. They examined the pathophysiological consequences of the slowing down or arrest of mucus drainage with particular reference to the proliferation of infectious agents and their penetration into respiratory mucus membranes.

Adrenergic beta-Agonists↗

PubMed1994

[Preliminary study on health effects in the residents exposed to liquefied petroleum gas].

Combustion of liquefied petroleum gas (LPG) can cause indoor air pollution with sulfur dioxide, nitrogen dioxide, total suspended particulate (TSP) and total hydrocarbons. Mice exposed to the pollutant air for three months showed lower ANAE, prolonged sleep time, increased PCE micronucleus in bone marrow, high positivity in Ames test for the lung homogenate and deformity of sperm in males, with obvious dose-response relationship. Investigation on a human population exposed to LPG for more than five years revealed irritating symptoms in respiratory tract, nose and eyes, and prevalence of pharyngitis, rhinitis and conjunctivitis increased significantly. Positive Ames test and micronucleus test in peripheral erythrocytes were detected in concentrated urine samples collected from them. It is postulated this may be associated with the mutagenic pollutants contained in the waste gas emitted by combustion of LPG.

Air Pollution, Indoor↗

PubMed1993

Air pollution levels, meteorological conditions and asthma symptoms.

We wanted to assess relations between the daily occurrence of asthma symptoms and fluctuations of air pollution concentrations and meteorological conditions. In a panel of 31 asthmatic patients residing in the town of Piteå in northern Sweden, severe symptoms of shortness of breath, wheeze, cough and phlegm were recorded in an asthma diary together with suspected causes. Sulphur dioxide, nitrogen dioxide, black smoke, relative humidity and temperature were used to evaluate the relationship to the environment. By using multivariate analyses, we found that daily variations in the particulate pollution levels, indicated by black smoke levels below the criteria limits, had significant effects on the risk of developing severe symptoms of shortness of breath. This association was stronger among 10 subjects, who had at least five incident days with severe shortness of breath. Meteorological conditions were not significant in the multivariate models. Cough and phlegm did not show significant relationships to any environmental condition that was evaluated. Only one-third of the subjects reported, at least once during the study, symptoms believed to be related to air pollutants, although we found significant correlations between the pollution levels and the frequency of pollution-related symptoms. We conclude that an association has been established for black smoke as pollutant and shortness of breath as respiratory symptom, and that in certain asthmatics, effects were occurring at lower particulate levels than suggested previously.

Adolescent↗

PubMedDate not supplied

[The status of the teeth and periodontal tissues of children living in an area polluted by the wastes from an aluminum plant].

The author compares dental, periodontal, and bone system status of children living in two regions characterized by different degrees and patterns of environmental pollution. Children living in regions polluted by aluminum plant waste (sulfur dioxide, nitrogen dioxide, carbon monoxide, dust, hydrogen fluoride) developed specific abnormalities because of body poisoning with fluorides, namely, dental fluorosis, osteoporosis and osteosclerosis of the bones; periodontal diseases in these children were more incident than in controls. These findings prompted the development of a complex of sanitary, technologic, health, therapeutic and prophylactic measures aimed at reduction of fluorine levels in the environment to the normal level and of dental diseases incidence among children living near the Tajik aluminum plant.

Adolescent↗