Dietary and pharmacological intervention to mitigate the cardiopulmonary effects of air pollution toxicity

BackgroundExposure to air pollution contributes importantly to excess morbidity and mortality. And while regulatory actions under the “Clean Air Act” have saved millions of lives by improving air quality, there are still millions of people in the U.S. who live in areas where particulate air pollution (PM) levels exceed the U.S. Environmental Protection Agency's National Ambient Air Quality Standards. Therefore, apart from such localities working to attain such standards the protection of the health of public and in particular those at high risk might benefit from interventional strategies that would ameliorate air pollution's adverse health effects. Because inflammation and oxidative stress appear to mediate the health effects of air pollution, one interventional approach to consider is the use of dietary supplementation or medication with anti-inflammatory or antioxidant properties to block the biological responses that initiate the pathophysiological process that culminates in adverse health effects.Scope of reviewThis article reviews the capability of dietary supplementation, such as antioxidant vitamins, polyunsaturated fatty acids, and medications as a strategy to mitigate air pollution-induced subclinical cardiopulmonary effects.Major conclusionsAntioxidant vitamins C and E protect the lungs against short-term ozone and PM exposure. Polyunsaturated fatty acids, such as fish oil and olive oil appear to offer protection against short-term air pollution-induced adverse cardiovascular responses.General significanceTaking dietary supplements or medications with antioxidant or anti-inflammatory properties has the potential to provide at least partial protection against air pollution-induced adverse health effects in those individuals who are known to be most susceptible, namely those with pre-existing respiratory and cardiovascular diseases. This article is part of a Special Issue entitled Air Pollution, edited by Wenjun Ding, Andrew J. Ghio and Weidong Wu.     

Air pollution abatement in Praque city

Air quality is a major concern in highly populated EU urban areas. European Commission adopted a series of directives to improve air quality. At local, regional, national levels efforts to reduce adverse impacts of poor air quality on human health are taken. Air quality management strategies are discussed and the measures proposed to improve air quality in Prague are compared. As road traffic is a major source for air pollution in EU cities, a Decision Support System (DSS) developed in the framework of the HEAVEN project aims to evaluate the environmental effects of near real-time traffic flows and Transport Demand Management Strategies (TDMS) in large urban areas.     

城市群空气污染综合评估范式与应用——以京津冀城市群PM2.5污染为例

城市群已成为中国城市发展的主要形式,城市化发展引发的一系列环境污染问题成为目前的研究重点之一,尤其是近年来明显的空气污染问题。由于传统的针对某一城市地区进行细致研究,难以解决在城市聚集的城市群下形成的区域性空气污染来源和影响机制等问题,使区域性空气污染造成的负面效应难以评估。通过构建综合评估模型范式,并运用空间分析,对京津冀168个区县2000年,2005年,2010年,2015年PM_2.5人口暴露风险、人类活动对PM_2.5的贡献、以及5种土地利用类型的"源汇"特征进行了实证研究。结果发现:(1)2000—2015年,京津冀城市群的人口暴露风险、空气污染分布、综合评估结果总体呈现北低南高的现象。(2)2000—2015年,各县域的人口暴露风险和空气污染的程度、范围呈上升趋势。不同的土地利用类型具有不同的源汇特征,且对污染的贡献不同。本研究通过综合评估模型范式对城市群或区域城市发展与空气质量的权衡关系模式开展量化解析,为城市的可持续发展提供了科学的范式和初步的实证示范。     

Evaluation of Anticipated Performance Index,biochemical, and physiological parameters of Cupressus arizonica Greene and Juniperus excelsa Bieb for greenbelt development and biomonitoring of air pollution

Abstract

Plants can be used naturally to mitigate environmental pollution, such as air pollution; however, it is important to evaluate plant susceptibility to air pollution when considering green space creation in urban areas. In this study, we investigated the biochemical and physiological parameters, including pH, and ascorbic acid, relative water, total chlorophyl, proline, soluble sugar, protein, and free amino acid contents of two gymnosperm tree species, Cupressus arizonica Greene and Juniperus excelsa Bieb. Using these data, we computed the Air Pollution Tolerance Index (APTI) and Anticipated Performance Index (API) of the trees at five sites in Isfahan, Iran, to determine their applicability for greenbelt establishment. Our results indicated that these evergreen species are good indicators of air pollution and can be used as an early warning tool for air pollution level that is harmful to human health.     

Characterizing spatiotemporal patterns of air pollution in China: A multiscale landscape approach

China’s tremendous economic growth in the past three decades has resulted in a number of environmental problems, including the deterioration of air quality. In particular, fine particulate matter (PM) has received increasing attention from scientists, governmental agencies, and the public due to its adverse impacts on human health. Monitoring the spatiotemporal patterns of air pollution is important for understanding its transport mechanisms and making effective environmental policies. The main goal of this study, therefore, was to quantify the spatial patterns and movement of air pollution in China at annual, daily, and hourly scales, so that the underlying drivers could be better understood. We used remote sensing data and landscape metrics together to capture spatiotemporal signatures of air pollution. Our results show that, at the annual scale, PM_2.5 concentrations in China increased gradually from 1999 to 2011, with the highest concentrations occurring in the North China Plain as well as the middle and lower reaches of the Yangtze River Basin. The total population affected by air pollution was about 975 million in 2010 (about 70% of China’s population). Our more detailed analysis on daily and hourly scale further revealed that a heavy air pollution event occurred, expanded, aggregated, and finally dissipated over Northern China during Oct. 6–12, 2014, suggesting that the Beijing-Tianjin-Hebei region a center of severe pollution. Crop stalks burning in agricultural areas in this region seemed to be one of the leading drivers, along with coal burning and transportation emissions. Our study demonstrates that spatial pattern analysis with landscape metrics is effective for analyzing source-sink dynamics of air pollution and its potential drivers. Our findings of major source areas and movement trajectories should be useful for making air pollution control policies to improve China’s air quality.     

Effects of air pollution and habitual exercise on the risk of death: a longitudinal cohort study

Background:Exercise may exacerbate the adverse health effects of air pollution by increasing the inhalation of air pollutants. We investigated the combined effects of long-term exposure to fine particle matter (PM_2.5) and habitual exercise on deaths from natural causes in Taiwan.Methods:We recruited 384 130 adults (aged ≥ 18 yr) with 842 394 medical examination records between 2001 and 2016, and followed all participants until May 31, 2019. We obtained vital data from the National Death Registry of Taiwan. We estimated PM_2.5 exposure using a satellite-based spatiotemporal model, and collected information on exercise habits using a standard self-administered questionnaire. We analyzed the data using a Cox regression model with time-dependent covariates.Results:A higher level of habitual exercise was associated with a lower risk of death from natural causes, compared with inactivity (hazard ratio [HR] 0.84, 95% confidence interval [CI] 0.80–0.88 for the moderate exercise group; HR 0.65, 95% CI 0.62–0.68 for the high exercise groups), whereas a higher PM_2.5 exposure was associated with a higher risk of death from natural causes compared with lower exposure (HR 1.02, 95% CI 0.98–1.07, and HR 1.15, 95% CI 1.10–1.20, for the moderate and high PM_2.5 exposure groups, respectively). Compared with inactive adults with high PM_2.5 exposure, adults with high levels of habitual exercise and low PM_2.5 exposure had a substantially lower risk of death from natural causes. We found a minor, but statistically significant, interaction effect between exercise and PM_2.5 exposure on risk of death (HR 1.03 95% CI 1.01–1.06). Subgroup analyses, stratified by PM_2.5 categories, suggested that moderate and high levels of exercise were associated with a lower risk of death in each PM_2.5 stratum, compared with inactivity.Interpretation:Increased levels of exercise and reduced PM_2.5 exposure are associated with a lower risk of death from natural causes. Habitual exercise can reduce risk regardless of the levels of PM_2.5 exposure. Our results suggest that exercise is a safe health improvement strategy, even for people residing in relatively polluted regions.

Air pollution and physical inactivity are both major public health challenges worldwide.¹ Air pollution was the fifth leading cause of disability related to health and accounted for 4.9 million deaths worldwide in 2017.² More than 91% of the global population lives in areas where air quality does not meet the World Health Organization (WHO) guidelines.³ In addition, physical inactivity was the fourth leading risk factor for death globally, accounting for 5.3 million deaths worldwide in 2012.⁴ The WHO has challenged its member states to reduce physical inactivity by 15% by 2030.⁵As people exercise, their ventilation rate increases, which increases the volume of air pollutants they inhale. This may exacerbate the adverse health effects of air pollutants. Thus, the risk–benefit relation between air pollution and exercise needs to be assessed to understand whether it is safe to exercise regularly in polluted regions. Indeed, some studies have shown that acute exposure to air pollution when exercising may override the benefits of exercise.^6,7 It is possible that the effects of long-term exposure to air pollution may be irreversible and cause a much larger disease burden than short-term exposure. Limited information exists on the combined effects of long-term exposure to air pollution and habitual exercise on human health, and findings have been inconsistent depending on health outcome. Three cohort studies have explored the relation between air pollution, physical activity and risk of death in Hong Kong,⁸ Denmark and the United States,⁹ with relatively small sample sizes.¹⁰ Therefore, we sought to investigate the combined effects of habitual exercise and long-term exposure to fine particle matter (PM_2.5) on the risk of death from natural causes (i.e., deaths not attributable to accident, suicide or homicide) using a longitudinal cohort of adults in Taiwan, where the annual PM_2.5 concentrations are 1.6 times higher than the WHO-recommended limit. We hypothesized that the beneficial effects of habitual exercise on risk of death may outweigh the risk of high levels of air pollutants inhaled during exercise.     

Fine particulate matter air pollution and atherosclerosis: Mechanistic insights

BackgroundAtherosclerosis is a progressive disease characterized by the accumulation of lipids and fibrous plaque in the arteries. Its etiology is very complicated and its risk factors primarily include genetic defects, smoking, hyperlipidemia, hypertension, lack of exercise, and infection. Recent studies suggest that fine particulate matter (PM_2.5) air pollution may also contribute to the development of atherosclerosis.Scope of reviewThe present review integrates current experimental evidence with mechanistic pathways whereby PM_2.5 exposure can promote the development of atherosclerosis.Major conclusionsPM_2.5-mediated enhancement of atherosclerosis is likely due to its pro-oxidant and pro-inflammatory effects, involving multiple organs, different cell types, and various molecular mediators.General significanceStudies about the effects of PM_2.5inhalation on atherosclerosis may yield a better understanding of the link between air pollution and major cardiovascular diseases, and provide useful information for policy makers to determine acceptable levels of PM_2.5 air quality. This article is part of a Special Issue entitled Air Pollution, edited by Wenjun Ding, Andrew J. Ghio and Weidong Wu.     

Obesity and the relation between joint exposure to ambient air pollutants and incident type 2 diabetes: A cohort study in UK Biobank

BackgroundAir pollution has been related to incidence of type 2 diabetes (T2D). We assessed the joint association of various air pollutants with the risk of T2D and examined potential modification by obesity status and genetic susceptibility on the relationship.Methods and findingsA total of 449,006 participants from UK Biobank free of T2D at baseline were included. Of all the study population, 90.9% were white and 45.7% were male. The participants had a mean age of 56.6 (SD 8.1) years old and a mean body mass index (BMI) of 27.4 (SD 4.8) kg/m². Ambient air pollutants, including particulate matter (PM) with diameters ≤2.5 μm (PM_2.5), between 2.5 μm and 10 μm (PM_2.5–10), nitrogen dioxide (NO₂), and nitric oxide (NO) were measured. An air pollution score was created to assess the joint exposure to the 4 air pollutants. During a median of 11 years follow-up, we documented 18,239 incident T2D cases. The air pollution score was significantly associated with a higher risk of T2D. Compared to the lowest quintile of air pollution score, the hazard ratio (HR) (95% confidence interval [CI]) for T2D was 1.05 (0.99 to 1.10, p = 0.11), 1.06 (1.00 to 1.11, p = 0.051), 1.09 (1.03 to 1.15, p = 0.002), and 1.12 (1.06 to 1.19, p < 0.001) for the second to fifth quintile, respectively, after adjustment for sociodemographic characteristics, lifestyle factors, genetic factors, and other covariates. In addition, we found a significant interaction between the air pollution score and obesity status on the risk of T2D (p-interaction < 0.001). The observed association was more pronounced among overweight and obese participants than in the normal-weight people. Genetic risk score (GRS) for T2D or obesity did not modify the relationship between air pollution and risk of T2D. Key study limitations include unavailable data on other potential T2D-related air pollutants and single-time measurement on air pollutants.ConclusionsWe found that various air pollutants PM_2.5, PM_2.5–10, NO_2, and NO, individually or jointly, were associated with an increased risk of T2D in the population. The stratified analyses indicate that such associations were more strongly associated with T2D risk among those with higher adiposity.

Xiang Li and co-workers study the potential influence of obesity on associations between air pollutants and incidence of type 2 diabetes.     

Assessing the Capacity of Plant Species to Accumulate Particulate Matter in Beijing,China

Air pollution causes serious problems in spring in northern China; therefore, studying the ability of different plants to accumulate particulate matter (PM) at the beginning of the growing season may benefit urban planners in their attempts to control air pollution. This study evaluated deposits of PM on the leaves and in the wax layer of 35 species (11 shrubs, 24 trees) in Beijing, China. Differences in the accumulation of PM were observed between species. Cephalotaxus sinensis, Euonymus japonicus, Broussonetia papyriferar, Koelreuteria paniculata and Quercus variabilis were all efficient in capturing small particles. The plants exhibiting high amounts of total PM accumulation (on leaf surfaces and/or in the wax layer), also showed comparatively high levels of PM accumulation across all particle sizes. A comparison of shrubs and trees did not reveal obvious differences in their ability to accumulate particles based on growth form; a combination of plantings with different growth forms can efficiently reduce airborne PM concentrations near the ground. To test the relationships between leaf traits and PM accumulation, leaf samples of selected species were observed using a scanning electron microscope. Growth forms with greater amounts of pubescence and increased roughness supported PM accumulation; the adaxial leaf surfaces collected more particles than the abaxial surfaces. The results of this study may inform the selection of species for urban green areas where the goal is to capture air pollutants and mitigate the adverse effects of air pollution on human health.     

Saharan Dust Impacts on Air Quality: What Are the Potential Health Risks in West Africa?

Despite the proximity of the Sahara, very few studies about dust impact on air quality and human health have been conducted in West Africa. The lack of data is a major constraint on our understanding of the impacts on human health in this area. We analyzed PM₁₀ concentrations and horizontal visibility recorded in four West African stations. The pollution levels often exceed the standards defined by many countries/regulatory authorities and have been associated with serious health risks outside Africa. Over the Sahelian stations, 45.6% of the days between November 2006 and March 2007 were likely to impact human health and the studied Sudanian population was exposed to potential health effects every 5 days.     

Air pollution could drive global dissemination of antibiotic resistance genes

Antibiotic-resistant pathogens pose a significant threat to human health. Several dispersal mechanisms have been described, but transport of both microbes and antibiotic resistance genes (ARGs) via atmospheric particles has received little attention as a pathway for global dissemination. These atmospheric particles can return to the Earth’s surface via rain or snowfall, and thus promote long-distance spread of ARGs. However, the diversity and abundance of ARGs in fresh snow has not been studied and their potential correlation with particulate air pollution is not well explored. Here, we characterized ARGs in 44 samples of fresh snow from major cities in China, three in North America, and one in Europe, spanning a gradient from pristine to heavily anthropogenically influenced ecosystems. High-throughput qPCR analysis of ARGs and mobile genetic elements (MGEs) provided strong indications that dissemination of ARGs in fresh snow could be exacerbated by air pollution, severely increasing the health risks of both air pollution and ARGs. We showed that snowfall did effectively spread ARGs from point sources over the Earth surface. Together our findings urge for better pollution control to reduce the risk of global dissemination of antibiotic resistance genes.Subject terms: Environmental sciences, Air microbiology     

Impact of nitrogen and climate change interactions on ambient air pollution and human health

Nitrogen oxides (NO_x) are important components of ambient and indoor air pollution and are emitted from a range of combustion sources, including on-road mobile sources, electric power generators, and non-road mobile sources. While anthropogenic sources dominate, NO_x is also formed by lightning strikes and wildland fires and is also emitted by soil. Reduced nitrogen (e.g., ammonia, NH₃) is also emitted by various sources, including fertilizer application and animal waste decomposition. Nitrogen oxides, ozone (O₃) and fine particulate matter (PM_2.5) pollution related to atmospheric emissions of nitrogen (N) and other pollutants can cause premature death and a variety of serious health effects. Climate change is expected to impact how N-related pollutants affect human health. For example, changes in temperature and precipitation patterns are projected to both lengthen the O₃ season and intensify high O₃ episodes in some areas. Other climate-related changes may increase the atmospheric release of N compounds through impacts on wildfire regimes, soil emissions, and biogenic emissions from terrestrial ecosystems. This paper examines the potential human health implications of climate change and N cycle interactions related to ambient air pollution.     

Repair of bulky DNA lesions deriving from polycyclic aromatic hydrocarbons

Genomic DNA is damaged by a variety of factors exerting an adverse effect on human health, such as environmental pollution, UV light, ionizing radiation, and toxic compounds. Air pollution with products of incomplete combustion of hydrocarbon fuels and wastes of various industries are main sources of polycyclic aromatic hydrocarbons, whose metabolites can damage DNA by forming bulky DNA adducts, which potentially lead to mutations and cancer. Nucleotide excision repair is the main pathway that eliminates these lesions in eukaryotic cells. The excision efficiency of bulky adducts depends on many factors, including the structure of a bulky substituent and the degree of DNA double helix distortion induced by a lesion. Clustered DNA lesions are the most dangerous for the cell. Several DNA repair systems cooperate to recognize and remove such lesions. The review focuses on the mechanisms that repair DNA with single and clustered bulky lesions, taking the natural carcinogen benzo[a]pyrene as an example.     

Novel approach to microbiological air monitoring in show caves

Air microbial pollution in touristic areas poses a risk for both the integrity of an ecosystem and human health. Microbiological monitoring together with environmental parameters monitoring allows for the assessment of the impacts and formulation of sound management decisions to protect humans and ecosystems. Four show caves from the Carpathian Mountains were selected for our study. The caves were sampled monthly to obtain an overview of the changes that occur over a yearly cycle. For the microbial monitoring, we used RIDA^®COUNT test plates, while the environmental parameters were monitored with a variety of devices. Second and third generations of microbes extracted from the plates were grown on specific media for the purpose of 16S rRNA and 18S rRNA extraction and taxa identification. The bacterial communities identified in the air samples in the four investigated show caves were dominated by Staphylococcus, while regarding the fungi communities, Penicillium was more likely to occur in the touristic part of the caves and Cladosporium in the non-visited passages. Together with data on number of visitors, number of bats and radon levels we were able understand the impact of tourists on the cave environment and to generate microbiological risk maps for human health. This type of comprehensive study can be used not only to protect the integrity of a touristic area from the impacts caused by the introduction of allochthonous organic matter, but also for the protection of the tourists and guides from potential pathogenic taxa.     

Air quality and its response to satellite-derived urban form in the Yangtze River Delta,China

Air pollution is one of the top environmental concerns and causes of deaths and various diseases worldwide. An important question for sustainable development is to what extent urban design can improve or degrade urban air quality. In this article, we explored the relationship between ground-based observations of air pollution and urban form in the Yangtze River Delta (YRD), the largest metropolitan region in China. We analyzed six criteria pollutants (SO₂, NO₂, PM₁₀, PM_2.5, CO, O₃) and summarized metric (air quality index, AQI) from 129 ambient air quality monitoring stations during 2015. Urban form was characterized using six spatial metrics, including the size, shape, regularity, fragmentation and traffic coupling factor of urban patches, based on satellite-derived land cover data. The results indicated that: (1) PM_2.5, PM₁₀ and O₃ were three primary pollutants in the YRD. The annual average AQI was 79, and the air quality was “moderate” for human health, with the highest and lowest AQI appeared in winter (107) and summer (60). Moreover, the air quality of the southern areas (Zhejiang province, AQI: 68) was generally better than the northern parts (Jiangsu province, AQI: 86). (2) Through the size and shape of urban patches, urban form had a significant effect on urban air quality in the YRD. PARA_MN (Mean Perimeter-area ratio), ENN_MN (Mean Euclidean Nearest Neighbor Distance), CA (Total Urban Area) and NP (Number of urban patches) had the most significant impacts on air quality. PM₁₀ and PM_2.5 were two important pollutants highly positively related to CA and NP, while negatively related to PARA_MN and ENN_MN. In addition, the polycentric urban form was associated with high air quality. (3) Land use configuration was an important indicator to describe the urban air quality. When buffer distance of spatial scale was 25 km, air quality showed the highest correlation with forest coverage. A high forest coverage rate contributed to the better air quality, increasing or preserving the forested areas would help mitigate the air pollution.     

Air pollution from natural and anthropic sources and male fertility

Exposure to air pollution has been clearly associated with a range of adverse health effects, including reproductive toxicity. However, a limited amount of research has been conducted to examine the association between air pollution and male reproductive outcomes, specially semen quality. We performed a systematic review (up to March 2017) to assess the impact of environmental and occupational exposure to air pollution on semen quality. Epidemiological studies focusing on air pollution exposures and male reproduction were identified by a search of the PUBMED, MEDLINE, EBSCO and TOXNET literature bases. Twenty-two studies were included which assess the impact of air pollutants (PM_2.5, PM₁₀, SO₂, NOx, O₃, PAHs) on main semen parameters (sperm concentration, motility, morphology), CASA parameters, DNA fragmentation, sperm aneuploidy and the level of reproductive hormones. The number of studies found significant results supporting the evidence that air pollution may affect: DNA fragmentation, morphology and motility.In summary, most studies concluded that outdoor air pollution affects at least one of the assessed semen parameters. However the diversity of air pollutants and semen parameters presented in the studies included in the review and different study design caused lack of consistency in results and difficulties in comparison.     

Clean air actions in China,PM2.5 exposure,and household medical expenditures: A quasi-experimental study

BackgroundExposure to air pollution, a leading contributor to the global burden of disease, can cause economic losses. Driven by clean air policies, the air quality in China, one of the most polluted countries, has improved rapidly since 2013. This has enabled a unique, quasi-experiment to assess the economic impact of air pollution empirically.Methods and findingsUsing a series of nation-scale longitudinal surveys in 2011, 2013, and 2015, we first examined the questionnaire-based medical expenditure changes before and after the policy intervention for air pollution. Using a state-of-the-art estimator of the historical concentration of particulate matters with diameter less than 2.5 μm (particulate matter (PM)_2.5), we further quantified the association between household medical expenditure and PM_2.5 using mixed-effect models of the repeated measurements from 26,511 households in 126 cities. Regression models suggest a robust linear association between reduced PM_2.5 and saved medical expenditures, since the association did not vary significantly across models with different covariate adjustments, subregions, or subpopulations. Each 10 μg/m³ reduction in PM_2.5 was associated with a saving of 251.6 (95% CI: 30.8, 472.3; p-value = 0.026) Yuan in per capita annual medical expenditure. However, due to limitations in data quality (e.g., self-reported expenditures), and imperfect control for unmeasured confounders or impact from concurrent healthcare reform in China, the causality underlying our findings should be further confirmed or refuted.ConclusionIn this study, we observed that compared with the PM_2.5 reduction in 2013, the PM_2.5 reduction in 2017 was associated with a saving of 552 (95% CI: 68, 1036) Yuan / (person × year), or approximately 736 billion Yuan (equivalent to 111 billion US dollar) per year nationally, which is equivalent to approximately 1% of the national gross domestic product of China.

In this observational study, Tao Xue and colleagues explore associations between medical expenses and changes to clean air policies in China since 2013.     

Decline in air pollution and change in prevalence in respiratory symptoms and chronic obstructive pulmonary disease in elderly women

Background

While adverse effects of exposure to air pollutants on respiratory health are well studied, little is known about the effect of a reduction in air pollutants on chronic respiratory symptoms and diseases. We investigated whether different declines in air pollution levels in industrialised and rural areas in Germany were associated with changes in respiratory health over a period of about 20 years.

Methods

We used data from the SALIA cohort study in Germany (Study on the influence of Air pollution on Lung function, Inflammation and Aging) to assess the association between the prevalence of chronic obstructive pulmonary disease (COPD) and chronic respiratory symptoms and the decline in air pollution exposure. In 1985-1994, 4874 women aged 55-years took part in the baseline investigation. Of these, 2116 participated in a questionnaire follow-up in 2006 and in a subgroup of 402 women lung function was tested in 2008-2009. Generalized estimating equation (GEE) models were used to estimate the effect of a reduction in air pollution on respiratory symptoms and diseases.

Results

Ambient air concentrations of particulate matter with aerodynamic size < 10 μm (PM₁₀) declined in average by 20 μg/m³. Prevalence of chronic cough with phlegm production and mild COPD at baseline investigation compared to follow-up was 9.5% vs. 13.3% and 8.6% vs. 18.2%, respectively. A steeper decline of PM₁₀ was observed in the industrialized areas in comparison to the rural area, this was associated with a weaker increase in prevalence of respiratory symptoms and COPD. Among women who never smoked, the prevalence of chronic cough with phlegm and mild COPD was estimated at 21.4% and 39.5%, respectively, if no air pollution reduction was assumed, and at 13.3% and 17.5%, respectively, if air pollution reduction was assumed.

Conclusion

We concluded that parallel to the decline of ambient air pollution over the last 20 years in the Ruhr area the age-related increase in chronic respiratory diseases and symptoms appears to attenuate in the population of elderly women.