Efforts to understand and mitigate the health effects of particulate matter (PM) air pollution have a rich and interesting history. This review focuses on six substantial lines of research that have been pursued since 1997 that have helped elucidate our understanding about the effects of PM on human health. There has been substantial progress in the evaluation of PM health effects at different time-scales of exposure and in the exploration of the shape of the concentration-response function. There has also been emerging evidence of PM-related cardiovascular health effects and growing knowledge regarding interconnected general pathophysiological pathways that link PM exposure with cardiopulmonary morbidity and mortality. Despite important gaps in scientific knowledge and continued reasons for some skepticism, a comprehensive evaluation of the research findings provides persuasive evidence that exposure to fine particulate air pollution has adverse effects on cardiopulmonary health. Although much of this research has been motivated by environmental public health policy, these results have important scientific, medical, and public health implications that are broader than debates over legally mandated air quality standards.

/pdf/health-effects-of-fine-particulate-air-pollution-lines-that-s831sp8jap.pdf

Health effects of fine particulate air pollution: lines that connect

Air pollution and health.

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

https://www.annualreviews.org/doi/pdf/10.1146/annurev.pu.15.050194.000543

Acute respiratory effects of particulate air pollution

INTRODUCTION Herein is the discussion of the 2006 A&WMA Critical Review1,2 on “Health Effects of Fine Particulate Air Pollution: Lines that Connect.” In the review, Drs. C. Arden Pope III and Douglas Dockery addressed the epidemiological evidence for the effects of particulate matter (PM) on human health indicators. The review documents substantial progress since the 1997 Critical Review3 in the areas of: (1) short-term exposure and mortality; (2) long-term exposure and mortality; (3) time scales of exposure; (4) the shape of the concentration-response function; (5) cardiovascular disease; and (6) biological plausibility. Invited and contributing discussants agree and disagree with points made in the review. Each discussion is self-contained and adds information relevant to the topic. Joint authorship of this article does not imply that a discussant subscribes to the opinions expressed by others. Commentaries are the opinions of the author only and do not necessarily reflect the positions of their respective organizations. In particular, Dr. Costa’s comments have not been reviewed by U.S. Environmental Protection Agency (EPA) and do not reflect official positions or policies of the agency. CRITICAL REVIEW DISCUSSION ISSN 1047-3289 J. Air & Waste Manage. Assoc. 56:1368–1380

Health effects of fine particulate air pollution: line that connect

Air pollution has been considered a hazard to human health. In the past decades, many studies highlighted the role of ambient airborne particulate matter (PM) as an important environmental pollutant for many different cardiopulmonary diseases and lung cancer. Numerous epidemiological studies in the past 30 years found a strong exposure-response relationship between PM for short-term effects (premature mortality, hospital admissions) and long-term or cumulative health effects (morbidity, lung cancer, cardiovascular and cardiopulmonary diseases, etc). Current research on airborne particle-induced health effects investigates the critical characteristics of particulate matter that determine their biological effects. Several independent groups of investigators have shown that the size of the airborne particles and their surface area determine the potential to elicit inflammatory injury, oxidative damage, and other biological effects. These effects are stronger for fine and ultrafine particles because they can penetrate deeper into the airways of the respiratory tract and can reach the alveoli in which 50% are retained in the lung parenchyma. Composition of the PM varies greatly and depends on many factors. The major components of PM are transition metals, ions (sulfate, nitrate), organic compound, quinoid stable radicals of carbonaceous material, minerals, reactive gases, and materials of biologic origin. Results from toxicological research have shown that PM have several mechanisms of adverse cellular effects, such as cytotoxicity through oxidative stress mechanisms, oxygen-free radical-generating activity, DNA oxidative damage, mutagenicity, and stimulation of proinflammatory factors. In this review, the results of the most recent epidemiological and toxicological studies are summarized. In general, the evaluation of most of these studies shows that the smaller the size of PM the higher the toxicity through mechanisms of oxidative stress and inflammation. Some studies showed that the extractable organic compounds (a variety of chemicals with mutagenic and cytotoxic properties) contribute to various mechanisms of cytotoxicity; in addition, the water-soluble faction (mainly transition metals with redox potential) play an important role in the initiation of oxidative DNA damage and membrane lipid peroxidation. Associations between chemical compositions and particle toxicity tend to be stronger for the fine and ultrafine PM size fractions. Vehicular exhaust particles are found to be most responsible for small-sized airborne PM air pollution in urban areas. With these aspects in mind, future research should aim at establishing a cleared picture of the cytotoxic and carcinogenic mechanisms of PM in the lungs, as well as mechanisms of formation during internal engine combustion processes and other sources of airborne fine particles of air pollution.

Airborne particulate matter and human health: toxicological assessment and importance of size and composition of particles for oxidative damage and carcinogenic mechanisms

R E Waller

Papers

Health effects of particulate pollution: reappraising the evidence

Epidemiologic evidence and the United States air quality standards.