Effects Of Particulate Air Pollution Research Articles

Epidemiologic studies on short-term effects of low levels of major ambient air pollution components.

Since the development of the World Health Organization (WHO) Air Quality Guidelines for Europe, a large number of epidemiologic studies have been published documenting effects of major air pollutants on health at concentrations below existing guidelines and standards. In this review, recent studies are discussed that permit some evaluation of short-term health effects observed at exposure levels lower than the current WHO Guidelines or U.S. Environmental Protection Agency (U.S. EPA) standards. Some studies have been conducted at concentration levels that never exceeded existing guidelines or standards. Other studies have been conducted at exposure levels sometimes exceeding current guidelines or standards. The published analyses of several of these studies permit evaluation of low-level health effects either because analyses were restricted to levels not exceeding the guidelines or graphic analyses were reported suggesting effects at these low levels. For ambient ozone, effects on lung function of subjects exercising outdoors have now been documented at 1-hr maximum levels not exceeding 120 micrograms/m3, i.e., half the current U.S. EPA standard. One study even suggests that such effects occur at levels below 100 micrograms/m3. Several studies are now available documenting effects of particulate air pollution on health in the virtual absence of SO2. Effects on mortality and hospital admissions for asthma have been documented at levels not exceeding 100 micrograms/m3, expressed as 24-hr average inhalable particles PM10 concentration. Effects on lung function, acute respiratory symptoms, and medication use have been found at 24-hr average PM10 levels not exceeding 115 micrograms/m3. When the WHO Air Quality Guidelines and the U.S. EPA standard for PM10 were developed, there were no studies available on health effects of PM10. In this review, we include nine studies documenting health effects of measured PM10 at low levels of exposure, indicating that there is now an entirely new epidemiologic database that can be evaluated in the process of revising current guidelines and standards. The low levels of exposure at which effects on health were seen underscore the urgent need for such reevaluations.

Particulate Air Pollution as a Predictor of Mortality in a Prospective Study of U.S. Adults

Time-series, cross-sectional, and prospective cohort studies have observed associations between mortality and particulate air pollution but have been limited by ecologic design or small number of subjects or study areas. The present study evaluates effects of particulate air pollution on mortality using data from a large cohort drawn from many study areas. We linked ambient air pollution data from 151 U.S. metropolitan areas in 1980 with individual risk factor on 552,138 adults who resided in these areas when enrolled in a prospective study in 1982. Deaths were ascertained through December, 1989. Exposure to sulfate and fine particulate air pollution, which is primarily from fossil fuel combustion, was estimated from national data bases. The relationships of air pollution to all-cause, lung cancer, and cardiopulmonary mortality was examined using multivariate analysis which controlled for smoking, education, and other risk factors. Although small compared with cigarette smoking, an association between mortality and particulate air pollution was observed. Adjusted relative risk ratios (and 95% confidence intervals) of all-cause mortality for the most polluted areas compared with the least polluted equaled 1.15 (1.09 to 1.22) and 1.17 (1.09 to 1.26) when using sulfate and fine particulate measures respectively. Particulate air pollution was associated with cardiopulmonary and lung cancer mortality but not with mortality due to other causes. Increased mortality is associated with sulfate and fine particulate air pollution at levels commonly found in U.S. cities. The increase in risk is not attributable to tobacco smoking, although other unmeasured correlates of pollution cannot be excluded with certainty.

Review of Epidemiological Evidence of Health Effects of Particulate Air Pollution

AbstractThis article summarizes epidemiological evidence of health effects of particulate air pollution. Acute exposure to elevated levels of particulate air pollution has been associated with increased cardiopulmonary mortality, increased hospitalization for respiratory disease, exacerbation of asthma, increased incidence and duration of respiratory symptoms, declines in lung function, and restricted activity. Small deficits in lung function, higher risk of chronic respiratory disease and symptoms, and increased mortality have also been associated with chronic exposure to respirable particulate air pollution. Health effects have been observed at levels common to many U.S. cites and at levels below current US. National Ambient Air Quality Standards. Although the biological mechanisms involved are poorly understood, recent epidemiological evidence supports the hypothesis that respirable particulate air pollution is an important risk factor for respiratory disease and cardiopulmonary mortality.

Acute respiratory effects of particulate air pollution.

In the 1930s, 40s, and 50s, several episodes of extreme air pollution focused attention on the potential for adverse health effects of air pollution. These included an episode in the Meuse Valley, Belgium, in December 1930 ( 15), an episode in Donora, Pennsylvania in 1948 (36), and several episodes in London, England (23, 44). The sudden large increases in sickness and death that accompanied such episodes demonstrated that air pollution can adversely affect human health. The increased mortality associated with such episodes provided the first quantitative measure of the adverse effects of air pollution. By the 1970s, a link had been well established between respiratory disease and particulate and/or sulfur-oxide air pollution, but still there remained disagreement as to the level of pollution that would significantly affect human health. In reviewing research published between 1968 and 1977, Holland and several other prominent British scientists ( 19) concluded that particulate and related air pollution at high levels pose hazards to human health, but that health effects of particulate pollution at lower concentrations could not be disentangled from health effects of other factors. Shy (45) responded by asserting that the review by Holland et al systematically discounted evidence of pollution-related health effects at contemporary pollution levels. Shy, and other reviewers ( 1, 12, 45, 54), contended that the cumulative weight of evidence provided sound reasons to believe that

Acute Respiratory Effects of Particulate Air Pollution

In recent decades, there has been remarkable growth in scientific research examining the multiple ways in which racism can adversely affect health. This interest has been driven in part by the striking persistence of racial/ethnic inequities in health and ...Read More

Effects of particulate air pollution on asthmatics.

Twenty-four asthmatic subjects in Denver were followed from January through March 1979, a three-month period in which Denver air pollution levels are generally high and variable. Dichotomous, virtual impactor samplers provided daily measurements (micrograms/m3) of inhaled particulate matter (total mass, sulfates, and nitrates) for coarse (2.5--15 micrograms in aerodynamic diameter) and fine fractions (less than 2.5 micrometers). Carbon monoxide, sulfur dioxide, ozone, temperature, and barometric pressure were also measured. Twice daily measurements of each subject's peak expiratory flow rates, use of as-needed aerosolized bronchodilators, and report of airways obstruction symptoms characteristic of asthma were tested for relationships to air pollutants using a random effects model across subjects. During the time actually observed, there were very few days in which high levels of suspended particulates were recorded. Of the environmental variables studied, only fine nitrates were associated with increased symptom reports and increased aerosolized bronchodilator usage.

Identification of Particulate Air Pollutants and Contaminants by Scanning Electron Microscopy and X-ray Spectrometry

Although our knowledge of the effects of gaseous air pollutants on plants is expanding rapidly, little is known about the identification and effects of particulate air pollutants on plant surfaces. Accordingly, a two-phase study was undertaken: (a) to identify and characterize the various particulate pollutants and contaminants found on leaf surfaces; and (b) to determine their physical and chemical effects. This report describes the progress made in the first phase of this study.Using a Jeolco JSM-U3 scanning electron microscope with double dispersive X-ray spectrometers, observations were made on intact leaf surfaces (upper and lower) and on various particulate samples. Studies were made on various crop plants as well as on native chaparral and desert plants. Most of the samples were coated with approximately 50-100 Å of gold-palladium metal, since “charging” is a definite problem with particulate specimens.