Short-term impact of particulate matter (PM2.5) on daily mortality among the over-75 age group in Madrid (Spain)

Association between atmospheric particulate matter and emergency room visits for cerebrovascular disease in Beijing, China

PURPOSE

The association between atmospheric particulate matter and emergency room visits for cerebrovascular disease were evaluated in Beijing.

METHODS

A generalized additive model was used to evaluate the associations between particulate matter and cerebrovascular disease, based on the daily data of meteorological elements, PM concentrations, and emergency room (ER) visits for cerebrovascular disease in Beijing from 2009 to 2012. Long-term trends and the effects of holidays, the day of the week, and confounding factors were controlled to determine the lag effect at 0-6 days. Single- and double-pollutant models were employed for different age and sex groups.

RESULTS

The effect of PM_2.5 concentration on the number of daily ER visits for cerebrovascular disease was much stronger than that of PM₁₀ concentration. PM_2.5 and PM₁₀ had maximum RR values of 1.096 and 1.054 at lag 6 for patients aged 61-75 years. For each inter-quartile range (IQR) increase in PM₁₀ concentration, the maximum RR values for the total, males, females, aged 15-60 years, aged 61-75 years, and aged > 75 years were 1.024, 1.044, 1.043, 1.038, 1.054, and 1.032, respectively. For each IQR increase in PM_2.5 concentration, the maximum RR values for the total, males, females, aged 15-60 years, aged 61-75 years, and aged > 75 years were 1.038, 1.064, 1.076, 1.054, 1.096, and 1.049, respectively. The RR values of the double-pollutant models were lower than those of the single-pollutant models.

CONCLUSION

This study showed that the effects of PM pollution on cerebrovascular disease were different among different gender and age groups, and aged 61-75 years were mostly sensitive to particulate matters. The effects of PM_2.5 on cerebrovascular disease were stronger than those of PM₁₀. Our results can provide scientific evidence for the local government to take effective measures to improve air quality and the health of residents.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s40201-021-00776-w.

Health Effects of Dust Storms on the South Edge of the Taklimakan Desert, China: A Survey-Based Approach

Dust storms have already become the most serious environmental problem on the south edge of the Taklimakan desert because of their frequent occurrences. To investigate the health effects of dust storms on public health in Moyu County, one of the most severe dust-storm-affected areas located at the south edge of the Taklimakan desert, China, primary data were collected from 1200 respondents by using a questionnaire survey for 15 health symptoms. The data were analyzed by comparing the mean tool (independent t-test and ANOVA) and the severity of different symptoms among different age groups. Principal component analysis (PCA) was applied to further analyze the multivariate relationships between meteorological factors, dust storm intensity, air pollution level, and severity degree of the different symptoms. The results show that significant correlations exist between dust storm intensity, air pollutants (PM_2.5, PM₁₀, O₃, SO₂, NO₂, and CO), meteorological factors, and health symptoms. During dusty weather, no matter the age group, the number of respondents who suffered from different health symptoms was higher compared to non-dusty days. Three types of dusty days were considered in this study: suspended dust, blowing dust, and sand storms. The impacts of sand storm weather on public health are stronger than those from blowing dust weather, suspended dust weather (haze), and non-dust weather. The people in the age groups above 60 years and below 15 years were more sensitive to different dust weather than people in the age groups between 15 and 60. “Dry throat with bitter taste”, “Depression”, “Dry and itchy throat”, and “Mouth ulcer” are the main symptoms caused by dust storms.

Variability of traffic noise pollution levels as a function of city size variables

Noise levels measured in 27 cities with different areas (from 0.6 km² to 59.27 km²) and populations (from approximately 2000 to 70,000 inhabitants) were compared with respect to five different urban characteristics (population, area, total street length, density, and linear density). Comparisons were conducted for both overall city noise levels and noise registered on five types of roads with different functionality using the Categorisation Method. The results showed that four of the five cities' characteristics presented a significant correlation with the noise levels (all except for density). The calculated correlations were better for noise levels in the different categories than the overall noise values, with higher explained variability on the streets with more traffic. Therefore, the road categorisation method can be used not only to assess the noise variations within cities, but also to better explain the effect of noise on the analysed city characteristics. The results of the calculated relationships enable the estimation of noise levels both currently and in future urban developments of noise values on different types of streets.

Pollutant-sex specific differences in respiratory hospitalization and mortality risk attributable to short-term exposure to ambient air pollution

BACKGROUND

Many studies have reported associations of individual pollutants with respiratory hospitalization and mortality based on different populations, which makes it difficult to directly compare adverse health effects among multiple air pollutants.

OBJECTIVES

The study goal is to compare acute respiratory-related hospitalization and mortality associated with short-term exposure to three ambient air pollutants and analyze differences in health risks by season, age and sex.

METHODS

Hourly measurements of air pollutants (ozone, NO₂, PM_2.5) and temperature were collected from ground-monitors for 24 cities along with daily hospitalization (1996-2012) and mortality (1984-2012) data. National associations between air pollutant and health outcome were estimated for season (warm, cold vs. year-round), age (base ≥ 1, seniors > 65), and sex (females ≥ 1 and males ≥ 1) using Bayesian hierarchical models.

RESULTS

Overall, the three air pollutants were significantly associated with acute respiratory health outcomes at different lag-days. For respiratory hospitalization, the increased risks in percent changes with 95% posterior intervals for a 10-unit increase in each pollutant were: ozone (lag1, 0.7% (0.4, 0.9)), NO₂ (lag0, 0.7% (0.1, 1.4)), and PM_2.5 (lag1, 1.3% (0.7, 1.9)). For respiratory mortality: ozone (lag2, 1.2% (0.4, 1.9)), NO₂ (lag1, 2.1% (0.6, 3.5)), and PM_2.5 (lag1, 0.6% (-1.0, 2.2)). While some differences in risk were observed by season and age group, sex-specific differences were more pronounced. Compared with males, females had a higher respiratory mortality risk (1.8% (0.6, 2.9) vs 0.5% (-0.3, 1.3)) from ozone, a higher respiratory hospitalization risk (0.9% (0.0, 1.8) vs 0.6% (-0.3, 1.4)) but lower mortality risk (1.4% (-1.0, 3.7) vs 2.2% (0.4, 4.0)) from NO₂, and a lower hospitalization risk (0.7% (-0.2, 1.7) vs 1.8% (1.0, 2.6)) from PM_2.5.

CONCLUSION

This study reports significant health effects of short-term exposure to three ambient air pollutants on respiratory hospitalization (ozone≈NO₂ < PM_2.5 per-10 unit; ozone>NO₂ ≈ PM_2.5 per-IQR) and mortality (ozone≈NO₂ > PM_2.5) in Canada. Pollutant-sex-specific differences were found, but inconclusive due to limited biological and physiological explanations. Further studies are warranted to understand the pollutant-sex specific differences.

Risk Assessment for People Exposed to PM2.5 and Constituents at Different Vertical Heights in an Urban Area of Taiwan

Environmental epidemiological studies have consistently reported associations between ambient particulate matter (PM) concentrations and everyday mortality/morbidity. Many urban dwellers in Asia live in high-rise apartment buildings; thus, the pollutant concentrations of their immediate outdoor environments are affected by the vertical distribution of pollutants in the atmosphere. The vertical distributions of pollutants provide unique information about their sources and dynamic transport in urban areas, as well as their relationship to people’s exposure at ground level, while the vertical distributions of pollutants have rarely been considered in exposure assessment. In the current study, PM concentrations (with aerodynamic diameters less than 1.0 μm (PM1), 2.5 μm (PM2.5), and 10 μm (PM10)), nanoparticles, black carbon (BC), and particle-bound polycyclic aromatic hydrocarbons (p-PAHs) were measured at different residential heights—6 m, 16 m, and 27 m—at Feng Chia University near a popular night market in Western Taiwan. PM2.5 data were further adopted for health risk estimations. In winter, the magnitude of PM1, PM2.5, and PM10 concentrations were 16 m > 6 m > 27 m; nanoparticle concentrations were 6 m > 27 m > 16 m; and BC and p-PAHs concentrations were 27 m > 16 m > 6 m. In summer, PM1, PM2.5, and PM10 concentrations ranged from 6 m > 16 m > 27 m; nanoparticle concentrations were 6 m > 16 m; and BC and p-PAHs concentrations were from 27 m > 16 m. PM and constituents concentrations during winter were significantly higher in the nighttime than those in daytime, and levels of PM1, PM2.5, and PM10 increased rapidly on 6 m and 16 m heights (but did not increase at 27 m) after 5 pm, whereas these trends became less significant in summer. Health risk analysis for PM2.5 concentrations showed a decrease in lung cancer mortality rate and an extended lifespan for residents living at 27 m. Overall, the current study investigated the vertical profile of particulate matters and analyzed health impacts of PM2.5 at different residential heights in urban area of Taiwan. As the distributions of PM and the constituents varied at different residential heights, exposure and risk assessment of particle concentrations with multiple sizes and various components at broader vertical heights should be further investigated.

Nrf2 mitigates prolonged PM2.5 exposure-triggered liver inflammation by positively regulating SIKE activity: Protection by Juglanin

Air pollution containing particulate matter (PM) less than 2.5 μm (PM2.5) plays an essential role in regulating hepatic disease. However, its molecular mechanism is not yet clear, lacking effective therapeutic strategies. In this study, we attempted to investigate the effects and mechanisms of PM2.5 exposure on hepatic injury by the in vitro and in vivo experiments. At first, we found that PM2.5 incubation led to a significant reduction of nuclear factor erythroid-derived 2-related factor 2 (Nrf2), along with markedly reduced expression of different anti-oxidants. Notably, suppressor of IKKε (SIKE), known as a negative regulator of the interferon pathway, was decreased in PM2.5-incubated cells, accompanied with increased activation of TANK-binding kinase 1 (TBK1) and nuclear factor-κB (NF-κB). The in vitro studies showed that Nrf2 positively regulated SIKE expression under the conditions with or without PM2.5. After PM2.5 treatment, Nrf2 knockdown further accelerated SIEK decrease and TBK1/NF-κB activation, and opposite results were observed in cells with Nrf2 over-expression. Subsequently, the gene loss- and gain-function analysis demonstrated that SIKE deficiency further aggravated inflammation and TBK1/NF-κB activation caused by PM2.5, which could be abrogated by SIKE over-expression. Importantly, SIKE-alleviated inflammation was mainly dependent on TBK1 activation. The in vivo studies confirmed that SIKE- and Nrf2-knockout mice showed significantly accelerated hepatic injury after long-term PM2.5 exposure through reducing inflammatory response and oxidative stress. Juglanin (Jug), mainly isolated from Polygonum aviculare, exhibits anti-inflammatory and anti-oxidant effects. We found that Jug could increase Nrf2 activation, and then up-regulated SIKE in cells and liver tissues, mitigating PM2.5-induced liver injury. Together, all these data demonstrated that Nrf2 might positively meditate SIKE to inhibit inflammatory and oxidative damage, ameliorating PM2.5-induced liver injury. Jug could be considered as an effective therapeutic strategy against this disease by improving Nrf2/SIKE signaling pathway.

Improvement of Skin Penetration, Antipollutant Activity and Skin Hydration of 7,3',4'-Trihydroxyisoflavone Cyclodextrin Inclusion Complex

As is known, many antioxidants from plant extracts have been used as additives in skincare products to prevent skin damage following overexposure to environmental pollutants. 7,3′,4′-trihydroxyisoflavone (734THIF), an isoflavone compound, possesses various biological activities, including antioxidant, antityrosinase, photodamage protection, and anticancer effects. Unfortunately, 734THIF has poor water solubility, which limits its skin penetration and absorption, and subsequently influences its biological activity. The aim of the present study was to investigate the mechanisms for the improvement in water solubility and skin penetration of 2-hydroxypropyl-β-cyclodextrin (HPBCD) inclusion complex with 734THIF (5-7HP). We also determined its photostability, antipollutant activity in HaCaT keratinocytes, and moisturizing effect in human subjects. Our results showed that 734THIF was embedded into the lipophilic inner cavity of HPBCD and its water solubility and skin penetration were thereby improved through amorphous transformation, surface area enhancement, and hydrogen bonding formation between 734THIF and HPBCD. In addition, 5-7HP inhibited PM-induced ROS generation and then downregulated ROS-mediated COX-2 and MMP9 production and AQP-3 consumption by inhibiting the phosphorylation of MAPKs. Consequently, we suggest that 5-7HP is a safe and photostable topical ingredient to enhance the skin penetration of 734THIF and skin hydration, and therefore 5-7HP may be used as an antipollutant additive in skin care products.

Bibliometric analysis of cardiometabolic disorders studies involving NO2, PM2.5 and noise exposure

BACKGROUND

This study uses bibliometric analysis to describe the state of research about the association of NO2, PM2.5 and noise exposures - three traffic-related pollutants - with cardiometabolic disorders.

METHODS

We retrieved references published 1994-2017 from Scopus and classified references with respect to exposure, health outcome and study design using index keywords. Temporal trend, top cited references, used index keywords and the number of hypothesis testing and non-hypothesis testing study design for each group were identified.

RESULTS

Results show PM2.5 is the most frequently studied exposure (47%), followed by both NO2 and PM2.5 exposure (29%). Only 3% of references considered multiple exposures between NO2 and/or PM2.5 and noise, and these were published after 2008. While we observed a growing trend in studies with NO2 and/or PM2.5 and noise and diabetes in the last decade, there is a diminishing trend in studies with noise and diabetes. Different patterns of study designs were found through H/NH ratio, the number of references classified as having a hypothesis (H)-testing design relative to the number of references classified as having a non-hypothesis (NH)-testing design. Studies with NO2 and/or PM2.5 exposure are more likely to have a H-testing design, while those with noise exposure are more likely to have a NH-testing design, such as cross-sectional study design.

CONCLUSIONS

We conclude with three themes about research trends. First, the study of simultaneous exposures to multiple pollutants is a current trend, and likely to continue. Second, the association between traffic-related pollutants and diabetes and metabolic symptoms is an area for growth in research. Third, the transition to the use of H-testing study designs to explore associations between noise and cardiometabolic outcomes may be supported by improved understanding of the mechanism of action, and/or improvements to the accuracy and precision of air pollution and noise exposure assessments for environmental health research.

Sources and Temporal Variations of Coarse Particulate Matter (PM) in Central Tehran, Iran

In this study, we used the positive matrix factorization (PMF) model to evaluate the sources of ambient coarse particulate matter (PM) and their temporal variations in two sampling sites, i.e., a school dormitory and a retirement home, located in central Tehran. 24-h ambient PM samples were collected using low-volume air samplers from May 2012 to June 2013. The collected filters were analyzed for their chemical components, including water-soluble ions, metals, and trace elements, which were used as the input to the PMF model. Our results indicated annual averages of 45.7 ± 3.8 µg/m3 and 36.2. ± 4.0 µg/m3 for coarse PM at the School dormitory and Tohid retirement home, respectively. Moreover, higher ambient coarse PM mass concentrations were observed in the warm season (53.3 ± 5.8 µg/m3 for school dormitory and 43.1 ± 6.1 µg/m3 for Tohid retirement home) as opposed to the cold season (41.4 ± 4.7 µg/m3 for school dormitory and 28.7 ± 4.6 µg/m3 for Tohid retirement home). Our PMF analysis also identified road dust, soil, and industry, and atmospherically processed coarse PM as the three sources of ambient coarse PM in central Tehran. Road dust, soil, and industry were the major sources of ambient coarse PM, contributing respectively to 74 ± 9% and 19 ± 2% of the total coarse PM mass concentration, while atmospherically aged aerosols had a rather minimal contribution of 7 ± 1% to total coarse PM mass concentration. The temporal trends of the resolved factors also revealed higher contributions of road dust to total ambient coarse PM during warm season as opposed to cold season, due to the increased resuspension rate from road surfaces as a result of higher wind speeds, and temperatures, combined with lower relative humidity. Similarly, higher resuspension rate of mechanically originated particulates resulted in higher warm-season time contributions of the soil factor. Results of this study clearly revealed the key role of road dust and non-tail pipe emissions on ambient coarse PM mass concentrations in crowded areas of central Tehran, and have important implications on the potential health impacts that can be caused by these difficult to mitigate sources of coarse PM.

Personal exposure to PM2.5 in Chinese rural households in the Yangtze River Delta

High levels of PM_2.5 exposure and associated health risks are of great concern in rural China. For this study, we used portable PM_2.5 monitors for monitoring concentrations online, recorded personal time-activity patterns, and analyzed the contribution from different microenvironments in rural areas of the Yangtze River Delta, China. The daily exposure levels of rural participants were 66 μg/m³ (SD 40) in winter and 65 μg/m³ (SD 16) in summer. Indoor exposure levels were usually higher than outdoor levels. The exposure levels during cooking in rural kitchens were 140 μg/m³ (SD 116) in winter and 121 μg/m³ (SD 70) in summer, the highest in all microenvironments. Winter and summer values were 252 μg/m³ (SD 103) and 204 μg/m³ (SD 105), respectively, for rural people using biomass for fuel, much higher than those for rural people using LPG and electricity. By combining PM_2.5 concentrations and time spent in different microenvironments, we found that 92% (winter) and 85% (summer) of personal exposure to PM_2.5 in rural areas was attributable to indoor microenvironments, of which kitchens accounted for 24% and 27%, respectively. Consequently, more effective policies and measures are needed to replace biomass fuel with LPG or electricity, which would benefit the health of the rural population in China.

Early warning signals for critical transitions in cardiopulmonary health, related to air pollution in an urban Chinese population

Respiratory, and cardio-cerebrovascular health-related diseases significantly threaten human health and together with air pollution form a complex pathophysiological system. Other complex biological systems show that increased variance and autocorrelations in time series may act as valid early warning signals for critical transitions. On population level, we determined the likelihood that increased variance and autocorrelation of hospital visit on cardiopulmonary disease preceded critical transitions in population health by human-pollution interactions. We investigated long-term hospital visits from a hospital in Nanjing City, China during 2006-2016 for the most important cardiopulmonary diseases likely to be influenced by air pollution: cerebrovascular accident disease (CVAD), coronary artery disease (CAD), chronic obstructive pulmonary disease (COPD), lung cancer disease (LCD), and the grouped categories of respiratory system disease (RESD) and cardio-cerebrovascular system disease (CCD). The time series of standard deviations (SDs) and autocorrelation at-lag-1 (AR-1) were studied as potential Early-Warning Indicators (EWIs) of transitions in population health. Elevated SDs provided an early warning for critical transitions in visit for LCD and overall CCD and CVAD, for the period of 2012-2013, after which a real transition of increased visit occurred for these disease categories. Statistical testing showed that these SDs were significantly increased (p < 0.1). The long-term air pollution together with intermittent pollution episodes may have triggered critical transitions in population health for cardiopulmonary disease. It is recommended to consider significant increases in variability in time series of relevant system parameters, such as visit, as early warning signs for future transitions in populations' health states.

Cold-related mortality vs heat-related mortality in a changing climate: A case study in Vilnius (Lithuania)

INTRODUCTION

Direct health effects of extreme temperatures are a significant environmental health problem in Lithuania, and could worsen further under climate change. This paper attempts to describe the change in environmental temperature conditions that the urban population of Vilnius could experience under climate change, and the effects such change could have on excess heat-related and cold-related mortality in two future periods within the 21st century.

METHODS

We modelled the urban climate of Vilnius for the summer and winter seasons during a sample period (2009-2015) and projected summertime and wintertime daily temperatures for two prospective periods, one in the near (2030-2045) and one in the far future (2085-2100), under the Representative Concentration Pathway (RCP) 8.5. We then analysed the historical relationship between temperature and mortality for the period 2009-2015, and estimated the projected mortality in the near future and far future periods under a changing climate and population, assuming alternatively no acclimatisation and acclimatisation to heat and cold based on a constant-percentile threshold temperature.

RESULTS

During the sample period 2009-2015 in summertime we observed an increase in daily mortality from a maximum daily temperature of 30 °C (the 96th percentile of the series), with an average of around 7 deaths per year. Under a no acclimatisation scenario, annual average heat-related mortality would rise to 24 deaths/year (95% CI: 8.4-38.4) in the near future and to 46 deaths/year (95% CI: 16.4-74.4) in the far future. Under a heat acclimatisation scenario, mortality would not increase significantly in the near or in the far future. Regarding wintertime cold-related mortality in the sample period 2009-2015, we observed increased mortality on days on which the minimum daily temperature fell below - 12 °C (the 7th percentile of the series), with an average of around 10 deaths a year. Keeping the threshold temperature constant, annual average cold-related mortality would decrease markedly in the near future, to 5 deaths/year (95% CI: 0.8-7.9) and even more in the far future, down to 0.44 deaths/year (95% C: 0.1-0.8). Assuming a "middle ground" between the acclimatisation and non-acclimatisation scenarios, the decrease in cold-related mortality will not compensate the increase in heat-related mortality.

CONCLUSION

Thermal extremes, both heat and cold, constitute a serious public health threat in Vilnius, and in a changing climate the decrease in mortality attributable to cold will not compensate for the increase in mortality attributable to heat. Study results reinforce the notion that public health prevention against thermal extremes should be designed as a dynamic, adaptive process from the inception.

Association between Airborne Fine Particulate Matter and Residents' Cardiovascular Diseases, Ischemic Heart Disease and Cerebral Vascular Disease Mortality in Areas with Lighter Air Pollution in China

Background: China began to carry out fine particulate matter (PM_2.5) monitoring in 2013 and the amount of related research is low, especially in areas with lighter air pollution. This study aims to explore the association between PM_2.5 and cardiovascular disease (CVD), ischemic heart disease (IHD) and cerebral vascular disease (EVD) mortality in areas with lighter air pollution. Methods: Data on resident mortality, air pollution and meteorology in Shenzhen during 2013–2015 were collected and analyzed using semi-parametric generalized additive models (GAM) with Poisson distribution of time series analysis. Results: Six pollutants were measured at seven air quality monitoring sites, including PM_2.5, PM₁₀, SO₂, NO₂, CO and O₃. The PM_2.5 daily average concentration was 35.0 ± 21.9 μg/m³; the daily average concentration range was from 7.1 μg/m³ to 137.1 μg/m³. PM_2.5 concentration had significant effects on CVD, IHD and EVD mortality. While PM_2.5 concentration of lag5 and lag02 rose by 10 μg/m³, the excess risk (ER) of CVD mortality were 1.50% (95% CI: 0.51–2.50%) and 2.09% (95% CI: 0.79–3.41%), respectively. While PM_2.5 concentration of lag2 and lag02 rose by 10 μg/m³, the ER of IHD mortality were 2.87% (95% CI: 0.71–5.07%) and 3.86% (95% CI: 1.17–6.63%), respectively. While PM_2.5 concentration of lag4 and lag04 rose by 10 μg/m³, the ER of EVD mortality were 2.09% (95% CI: 2.28–3.92%) and 3.08% (95% CI: 0.68–5.53%), respectively. Conclusions: PM_2.5 increased CVD mortality. The government needs to strengthen the governance of air pollution in areas with a slight pollution.

Refined source apportionment of coal combustion sources by using single particle mass spectrometry

In this study, samples of three typical coal combustion source types, including Domestic bulk coal combustion (DBCC), Heat supply station (HSS), and Power plant (PP) were sampled and large sets of their mass spectra were obtained and analyzed by SPAMS during winter in a megacity in China. A primary goal of this study involves determining representative size-resolved single particle mass spectral signatures of three source types that can be used in source apportionment activities. Chemical types describe the majority of the particles of each source type were extracted by ART-2a algorithm with distinct size characteristics, and the corresponding tracer signals were identified. Mass spectral signatures from three source types were different from each other, and the tracer signals were effective in distinguishing different source types. A high size-resolution source apportionment method were proposed in this study through matching sources' mass spectral signatures to particle spectra in a twelve days ambient sampling to source apportion the particles. Contributions of three source types got different size characteristics, as HSS source got higher contribution in smaller sizes, But PP source got higher contributions as size increased. Source contributions were also quantified during two typical haze episodes, and results indicated that HSS source (for central-heating) and DBCC source (for domestic heating and cooking) may contribute evidently to pollution formation.

Heat and health in Antwerp under climate change: Projected impacts and implications for prevention

BACKGROUND

Excessive summer heat is a serious environmental health problem in several European cities. Heat-related mortality and morbidity is likely to increase under climate change scenarios without adequate prevention based on locally relevant evidence.

METHODS

We modelled the urban climate of Antwerp for the summer season during the period 1986-2015, and projected summer daily temperatures for two periods, one in the near (2026-2045) and one in the far future (2081-2100), under the Representative Concentration Pathway (RCP) 8.5. We then analysed the relationship between temperature and mortality, as well as with hospital admissions for the period 2009-2013, and estimated the projected mortality in the near future and far future periods under changing climate and population, assuming alternatively no acclimatization and acclimatization based on a constant threshold percentile temperature.

RESULTS

During the sample period 2009-2013 we observed an increase in daily mortality from a maximum daily temperature of 26°C, or the 89th percentile of the maximum daily temperature series. The annual average heat-related mortality in this period was 13.4 persons (95% CI: 3.8-23.4). No effect of heat was observed in the case of hospital admissions due to cardiorespiratory causes. Under a no acclimatization scenario, annual average heat-related mortality is multiplied by a factor of 1.7 in the near future (24.1deaths/year CI 95%: 6.78-41.94) and by a factor of 4.5 in the far future (60.38deaths/year CI 95%: 17.00-105.11). Under a heat acclimatization scenario, mortality does not increase significantly in the near or in the far future.

CONCLUSION

These results highlight the importance of a long-term perspective in the public health prevention of heat exposure, particularly in the context of a changing climate, and the calibration of existing prevention activities in light of locally relevant evidence.

Causality test of ambient fine particles and human influenza in Taiwan: Age group-specific disparity and geographic heterogeneity

Influenza is a major global public health problem, with serious outcomes that can result in hospitalization or even death. We investigate the causal relationship between human influenza cases and air pollution, quantified by ambient fine particles <2.5μm in aerodynamic diameter (PM_2.5). A modified Granger causality test is proposed to ascertain age group-specific causal relationship between weekly influenza cases and weekly adjusted accumulative PM_2.5 from 2009 to 2015 in 11 cities and counties in Taiwan. We examine the causal relationship based on posterior probabilities of the log-linear integer-valued GARCH (generalized autoregressive conditional heteroscedastic) model with covariates, which enable us to handle characteristics of influenza data such as integer-value, lagged dependence, and over-dispersion. The resulting posterior probabilities show that the adult age group (25-64) and the elderly group in New Taipei in the north and cities in southwestern part of Taiwan are strongly affected by ambient fine particles. Moreover, the elderly group is clearly affected in all study sites. Globalization and economic growth have resulted in increased ambient air pollution (including PM_2.5) and subsequently substantial public health concerns in the West Pacific region. Minimizing exposure to air pollutants is particularly important for the elderly and susceptible individuals with respiratory diseases.

A Global Perspective of Fine Particulate Matter Pollution and Its Health Effects

Fine particulate matter (PM) in the ambient air is implicated in a variety of human health issues throughout the globe. Regulation of fine PM in the atmosphere requires information on the dimension of the problem with respect to variations in concentrations and sources. To understand the current status of fine particles in the atmosphere and their potential harmful health effects in different regions of the world this review article was prepared based on peer-reviewed scientific papers, scientific reports, and database from government organizations published after the year 2000 to evaluate the global scenario of the PM_2.5 (particles <2.5 μm in aerodynamic diameter), its exceedance of national and international standards, sources, mechanism of toxicity, and harmful health effects of PM_2.5 and its components. PM_2.5 levels and exceedances of national and international standards were several times higher in Asian countries, while levels in Europe and USA were mostly well below the respective standards. Vehicular traffic has a significant influence on PM_2.5 levels in urban areas; followed by combustion activities (biomass, industrial, and waste burning) and road dust. In urban atmosphere, fine particles are mostly associated with different health effects with old aged people, pregnant women, and more so children being the most susceptible ones. Fine PM chemical constituents severely effect health due to their carcinogenic or mutagenic nature. Most of the research indicated an exceedance of fine PM level of the standards with a diverse array of health effects based on PM_2.5 chemical constituents. Emission reduction policies with epidemiological studies are needed to understand the benefits of sustainable control measures for fine PM mitigation.

Mass spectra features of biomass burning boiler and coal burning boiler emitted particles by single particle aerosol mass spectrometer

In this study, single particle mass spectra signatures of both coal burning boiler and biomass burning boiler emitted particles were studied. Particle samples were suspended in clean Resuspension Chamber, and analyzed by ELPI and SPAMS simultaneously. The size distribution of BBB (biomass burning boiler sample) and CBB (coal burning boiler sample) are different, as BBB peaks at smaller size, and CBB peaks at larger size. Mass spectra signatures of two samples were studied by analyzing the average mass spectrum of each particle cluster extracted by ART-2a in different size ranges. In conclusion, BBB sample mostly consists of OC and EC containing particles, and a small fraction of K-rich particles in the size range of 0.2-0.5μm. In 0.5-1.0μm, BBB sample consists of EC, OC, K-rich and Al_Silicate containing particles; CBB sample consists of EC, ECOC containing particles, while Al_Silicate (including Al_Ca_Ti_Silicate, Al_Ti_Silicate, Al_Silicate) containing particles got higher fractions as size increase. The similarity of single particle mass spectrum signatures between two samples were studied by analyzing the dot product, results indicated that part of the single particle mass spectra of two samples in the same size range are similar, which bring challenge to the future source apportionment activity by using single particle aerosol mass spectrometer. Results of this study will provide physicochemical information of important sources which contribute to particle pollution, and will support source apportionment activities.

Levels and Health Risk Assessment of PM10 Aerosol in Brno, Czech Republic

OBJECTIVE

The main effort of this work was to evaluate the situation of the atmosphere in selected regions of Brno during the years 2009-2013 and to estimate health risks which might come up due to the increased concentrations of airborne particulate matter.

METHODS

PM₁₀ samples were collected in four areas varying in degree of automobile traffic using automatic and gravimetric sampling methods. PM₁₀ concentrations were assessed using Spearman's rank correlation coefficient. Health risks were estimated based on calculation of relative risks and population for four health endpoints. The selected health outcomes were premature mortality, cardiovascular disease, respiratory disease, and chronic bronchitis.

RESULTS

The highest PM₁₀ concentrations were measured in two regions with high traffic loads T1, T2 and background region B2. The values were 34.33 ± 11.52 µg·m^-3 in 2010, 34.87 ± 12.03 µg·m^-3 in 2013 and 34.52 ± 8.81 µg·m^-3 in 2009, respectively. The highest correlation was between T1 and T2 having Spearman's correlation coefficient 0.888 followed by T1-B1 pair with coefficient 0.886. For all health outcomes, the highest health effect of PM (E) was determined for T2 site in 2010 which was 48 ± 14, 49 ± 21, 44 ± 19 and 24 ± 10 for premature mortality, cardiovascular disease, respiratory disease, and chronic bronchitis, respectively.

CONCLUSION

The concentrations are highly correlated, especially in traffic regions. The annual concentrations did not exceed the legislation limit but 24-hours limit was exceeded more than two times in several cases. The highest number of cases with a given health outcome was estimated in traffic regions especially for cardiovascular disease and premature mortality.

Human health impact assessment of exposure to particulate matter: an AirQ software modeling

The aim of this study was to assess the health impacts related to particulate matter less than 10 μm (PM₁₀) exposure in the city of Yazd, Iran. For this aim, AirQ 2.2.3 software was used to model relationship between short-term exposure to PM₁₀ and disease cases proposed by the World Health Organization (WHO). The annual mean concentration of PM₁₀ was 97 μg/m³. The maximum concentration value of PM₁₀ was measured during the summer (731 μg/m³). 4.988% (95%CI: 3.381-6.542%) of the total mortality, 7.3% (95%CI; 4.19-10.21%) of cardiovascular mortality, and 10.21% (95%CI; 4.19-14.89%) of respiratory mortality were related to the PM₁₀ concentrations. Consequently, the AirQ software can provide valuable information about the importance of air pollution and the substantial impacts of PM₁₀ on the society for policymakers.

Where do uncertainties reside within environmental risk assessments? Testing UnISERA, a guide for uncertainty assessment

A means for identifying and prioritising the treatment of uncertainty (UnISERA) in environmental risk assessments (ERAs) is tested, using three risk domains where ERA is an established requirement and one in which ERA practice is emerging. UnISERA's development draws on 19 expert elicitations across genetically modified higher plants, particulate matter, and agricultural pesticide release and is stress tested here for engineered nanomaterials (ENM). We are concerned with the severity of uncertainty; its nature; and its location across four accepted stages of ERAs. Using an established uncertainty scale, the risk characterisation stage of ERA harbours the highest severity level of uncertainty, associated with estimating, aggregating and evaluating expressions of risk. Combined epistemic and aleatory uncertainty is the dominant nature of uncertainty. The dominant location of uncertainty is associated with data in problem formulation, exposure assessment and effects assessment. Testing UnISERA produced agreements of 55%, 90%, and 80% for the severity level, nature and location dimensions of uncertainty between the combined case studies and the ENM stress test. UnISERA enables environmental risk analysts to prioritise risk assessment phases, groups of tasks, or individual ERA tasks and it can direct them towards established methods for uncertainty treatment.

Evaluation of short-term mortality attributable to particulate matter pollution in Spain

According to the WHO, 3 million deaths are attributable to air pollution due to particulate matter (PM) world-wide. However, there are no specific updated studies which calculate short-term PM-related cause specific mortality in Spain. The objective is to quantify the relative risks (RRs) and attributable risks (ARs) of daily mortality associated with PM₁₀ concentrations, registered in Spanish provinces and to calculate the number of PM-related deaths. We calculated daily mortality due to natural (ICD-10: A00 R99), circulatory (ICD-10: I00 I99) and respiratory causes (ICD-10: J00 J99) for each province across the period 2000-2009. Mean daily concentrations of PM₁₀, NO₂ and O₃ was used. For the estimate of RRs and ARs, we used generalised linear models with a Poisson link. A meta-analysis was used to estimate RRs and ARs in the provinces with statically significant results. The overall RRs obtained for these provinces, corresponding to increases of 10 μ g/m³ in PM₁₀ concentrations were 1.009 (95% CI: 1.006 1011) for natural, 1.026 (95% CI: 1.019 1033) for respiratory, and 1.009 (95% CI: 1.006 1012) for circulatory-cause mortality. This amounted to an annual overall total of 2683 deaths (95% CI: 852 4354) due to natural, 651 (95% CI: 359 1026) due to respiratory, and 556 (95% CI: 116 1012) due to circulatory causes, with 90% of this mortality lying below the WHO guideline values. This study provides an updated estimate of the effect had by this type of pollutant on causes of mortality, and constitutes an important basis for reinforcing public health measures.

Saharan dust and the impact on adult and elderly allergic patients: the effect of threshold values in the northern sector of Gran Canaria, Spain

Gran Canaria Island is frequently impacted by Saharan dust, a health hazard of particular concern to the island population and health agencies. Airborne mineral dust has the severest impact on the higher age groups of the population, and those with respiratory conditions; despite that, on average, the ambient particulate matter (PM) concentrations fall within international PM guidelines. During 2010 and 2011, an epidemiological survey, in parallel with an air quality study, was conducted at the Dr Negrín hospital in Gran Canaria. This included the quarterly monitoring of outpatients and recording of emergency patients with respiratory diseases, together with the measurement of aerosol, meteorological, and PM-related air quality levels. The finer more toxic particles were collected with PM_2.5 (particulate matter with aerodynamic diameter less than 2.5 μm) aerosol samplers. The filter samples were gravimetrically and chemically analyzed for their elemental, water-soluble ions, carbon, and mineralogical contents. Individual particle morphology was measured by Scanning Electron Microscopy. Statistical analysis of the chemical and clinical data included the analysis of variance and calculation of Spearman correlation coefficients. No statistically significant relations were found between the allergic control group, the emergency room admissions, pulmonary conditions, medication, and elevated Saharan dust levels. However, changing environmental conditions, such as an increase in humidity or a reduction in ambient air temperature made a significant difference to the outcomes recorded on the health statements of the allergic and respiratory illness groups of the Gran Canary population.

Impact of air pollution and temperature on adverse birth outcomes: Madrid, 2001-2009

BACKGROUND/OBJECTIVES

Low birth weight (<2500 g) (LBW), premature birth (<37 weeks of gestation) (PB), and late foetal death (<24 h of life) (LFD) are causes of perinatal morbi-mortality, with short- and long-term social and economic health impacts. This study sought to identify gestational windows of susceptibility during pregnancy and to analyse and quantify the impact of different air pollutants, noise and temperature on the adverse birth outcomes.

METHODS

Time-series study to assess the impact of mean daily PM_2.5, NO₂ and O₃ (μg/m³), mean daily diurnal (Leqd) and nocturnal (Leqn) noise levels (dB(A)), maximum and minimum daily temperatures (°C) on the number of births with LBW, PB or LFD in Madrid across the period 2001-2009. We controlled for linear trend, seasonality and autoregression. Poisson regression models were fitted for quantification of the results. The final models were expressed as relative risk (RR) and population attributable risk (PAR).

RESULTS

Leqd was observed to have the following impacts in LBW: at onset of gestation, in the second trimester and in the week of birth itself. NO₂ had an impact in the second trimester. In the case of PB, the following: Leqd in the second trimester, Leqn in the week before birth and PM_2.5 in the second trimester. In the case of LFD, impacts were observed for both PM_2.5 in the third trimester, and minimum temperature. O₃ proved significant in the first trimester for LBW and PB, and in the second trimester for LFD.

CONCLUSIONS

Pollutants concentrations, noise and temperature influenced the weekly average of new-borns with LBW, PB and LFD in Madrid. Special note should be taken of the effect of diurnal noise on LBW across the entire pregnancy. The exposure of pregnant population to the environmental factors analysed should therefore be controlled with a view to reducing perinatal morbi-mortality.

Effect of Environmental Factors on Low Weight in Non-Premature Births: A Time Series Analysis

OBJECTIVE

Exposure to pollutants during pregnancy has been related to adverse birth outcomes. LBW can give rise to lifelong impairments. Prematurity is the leading cause of LBW, yet few studies have attempted to analyse how environmental factors can influence LBW in infants who are not premature. This study therefore sought to analyse the influence of air pollution, noise levels and temperature on LBW in non-premature births in Madrid during the period 2001-2009.

METHODS

Ecological time-series study to assess the impact of PM2.5, NO2 and O3 concentrations, noise levels, and temperatures on LBW among non-premature infants across the period 2001-2009. Our analysis extended to infants having birth weights of 1,500 g to 2,500 g (VLBW) and less than 1,500 g (ELBW). Environmental variables were lagged until 37 weeks with respect to the date of birth, and cross-correlation functions were used to identify explaining lags. Results were quantified using Poisson regression models.

RESULTS

Across the study period 298,705 births were registered in Madrid, 3,290 of which had LBW; of this latter total, 1,492 were non-premature. PM2.5 was the only pollutant to show an association with the three variables of LBW in non-premature births. This association occurred at around the third month of gestation for LBW and VLBW (LBW: lag 23 and VLBW: lag 25), and at around the eighth month of gestation for ELBW (lag 6). Leqd was linked to LBW at lag zero. The RR of PM2.5 on LBW was 1.01 (1.00 1.03). The RR of Leqd on LBW was 1.09 (0.99 1.19)(p<0.1).

CONCLUSIONS

The results obtained indicate that PM2.5 had influence on LBW. The adoption of measures aimed at reducing the number of vehicles would serve to lower pregnant women's exposure. In the case of noise should be limited the exposure to high levels during the final weeks of pregnancy.

Effect of heat waves on morbidity and mortality due to Parkinson's disease in Madrid: A time-series analysis

BACKGROUND

Parkinson's disease (PD) is one of the factors which are associated with a higher risk of mortality during heat waves. The use of certain neuroleptic medications to control some of this disease's complications would appear to be related to an increase in heat-related mortality.

OBJECTIVE

To analyse the relationship and quantify the short-term effect of high temperatures during heat wave episodes in Madrid on daily mortality and PD-related hospital admissions.

METHODS

We used an ecological time-series study and fit Poisson regression models. We analysed the daily number of deaths due to PD and the number of daily PD-related emergency hospital admissions in the city of Madrid, using maximum daily temperature (°C) as the main environmental variable and chemical air pollution as covariates. We controlled for trend, seasonalities, and the autoregressive nature of the series.

RESULTS

There was a maximum daily temperature of 30°C at which PD-related admissions were at a minimum. Similarly, a temperature of 34°C coincides with an increase in the number of admissions. For PD-related admissions, the Relative Risk (RR) for every increase of 1°C above the threshold temperature was 1.13 IC95%:(1.03-1.23) at lags 1 and 5; and for daily PD-related mortality, the RR was 1.14 IC95%:(1.01-1.28) at lag 3.

CONCLUSION

Our results indicate that suffering from PD is a risk factor that contributes to the excess morbidity and mortality associated with high temperatures, and is relevant from the standpoint of public health prevention plans.

Short-term population-based non-linear concentration-response associations between fine particulate matter and respiratory diseases in Taipei (Taiwan): a spatiotemporal analysis

Fine particulate matter <2.5 μm (PM2.5) has been associated with human health issues; however, findings regarding the influence of PM2.5 on respiratory disease remain inconsistent. The short-term, population-based association between the respiratory clinic visits of children and PM2.5 exposure levels were investigated by considering both the spatiotemporal distributions of ambient pollution and clinic visit data. We applied a spatiotemporal structured additive regression model to examine the concentration-response (C-R) association between children's respiratory clinic visits and PM2.5 concentrations. This analysis was separately performed on three respiratory disease categories that were selected from the Taiwanese National Health Insurance database, which includes 41 districts in the Taipei area of Taiwan from 2005 to 2007. The findings reveal a non-linear C-R pattern of PM2.5, particularly in acute respiratory infections. However, a PM2.5 increase at relatively lower levels can elevate the same-day respiratory health risks of both preschool children (<6 years old) and schoolchildren (6-14 years old). In preschool children, same-day health risks rise when concentrations increase from 0.76 to 7.44 μg/m(3), and in schoolchildren, same-day health risks rise when concentrations increase from 0.76 to 7.52 μg/m(3). Changes in PM2.5 levels generally exhibited no significant association with same-day respiratory risks, except in instances where PM2.5 levels are extremely high, and these occurrences do exhibit a significant positive influence on respiratory health that is especially notable in schoolchildren. A significant high relative rate of respiratory clinic visits are concentrated in highly populated areas. We highlight the non-linearity of the respiratory health effects of PM2.5 on children to investigate this population-based association. The C-R relationship in this study can provide a highly valuable alternative for assessing the effects of ambient air pollution on human health.

Impact of ambient fine particulate matter (PM2.5) exposure on the risk of influenza-like-illness: a time-series analysis in Beijing, China

BACKGROUND

Air pollution in Beijing, especially PM2.5, has received increasing attention in the past years. Although exposure to PM2.5 has been linked to many health issues, few studies have quantified the impact of PM2.5 on the risk of influenza-like illness (ILI). The aim of our study is to investigate the association between daily PM2.5 and ILI risk in Beijing, by means of a generalized additive model.

METHODS

Daily PM2.5, meteorological factors, and influenza-like illness (ILI) counts during January 1, 2008 to December 31, 2014 were retrieved. An inverse Gaussian generalized additive model with log link function was used to flexibly model the nonlinear relationship between the PM2.5 (single- and multiday lagged exposure) and ILI risk, adjusted for the weather conditions, seasonal and year trends. We also assessed if the effect of PM2.5 differs during flu season versus non-flu season by including the interaction term between PM2.5 and flu season in the model. Furthermore, a stratified analysis by age groups was conducted to investigate how the effect of PM2.5 differs across age groups.

RESULTS

Our findings suggested a strong positive relationships between PM2.5 and ILI risk at the flu season (October-April) (p-value < 0.001), after adjusting for the effects of ambient daily temperature and humidity, month and year; whereas no significant association was identified at the non-flu season (May-September) (p-value = 0.174). A short term delayed effect of PM2.5 was also identified with 2-day moving average (current day to the previous day) of PM2.5 yielding the best predictive power. Furthermore, PM2.5 was strongly associated with ILI risk across all age groups (p-value < 0.001) at the flu season, but the effect was the most pronounced among adults (age 25-59), followed by young adults (age 15-24), school children (age 5-14) and the elderly (age 60+) and the effect of PM2.5 was the least pronounced for children under 5 years of age (age < 5).

CONCLUSIONS

Ambient PM2.5 concentrations were significantly associated with ILI risk in Beijing at the flu season and the effect of PM2.5 differed across age groups, in Beijing, China.

Insights into the chemical characterization and sources of PM(2.5) in Beijing at a 1-h time resolution

As the widespread application of online instruments penetrates the environmental fields, it is interesting to investigate the sources of fine particulate matter (PM2.5) based on the data monitored by online instruments. In this study, online analyzers with 1-h time resolution were employed to observe PM2.5 composition data, including carbon components, inorganic ions, heavy metals and gas pollutants, during a summer in Beijing. Chemical characteristics, temporal patterns and sources of PM2.5 are discussed. On the basis of hourly data, the mean concentration value of PM2.5 was 62.16±39.37 μg m(-3) (ranging from 6.69 to 183.67 μg m(-3)). The average concentrations of NO3(-), SO4(2-), NH4(+), OC and EC, the major chemical species, were 15.18±13.12, 14.80±14.53, 8.90±9.51, 9.32±4.16 and 3.08±1.43 μg m(-3), respectively. The concentration of PM2.5 varied during the online-sampling period, initially increasing and then subsequently decreasing. Three factor analysis models, including principal component analysis (PCA), positive matrix factorization (PMF) and Multilinear Engine 2 (ME2), were applied to apportion the PM2.5 sources. Source apportionment results obtained by the three different models were in agreement. Four sources were identified in Beijing during the sampling campaign, including secondary sources (38-39%), crustal dust (17-22%), vehicle exhaust (25-28%) and coal combustion (15-16%). Similar source profiles and contributions of PM2.5 were derived from ME2 and PMF, indicating the results of the two models are reasonable. The finding provides information that could be exploited for regular air control strategies.

Comparison of the effects of extreme temperatures on daily mortality in Madrid (Spain), by age group: The need for a cold wave prevention plan

A number of studies have shown that there is a time trend towards a reduction in the effects of heat on mortality. In the case of cold, however, there is practically no research of this type and so there is no clearly defined time trend of the impact of cold on mortality. Furthermore, no other specific studies have yet analysed the time trend of the impact of both thermal extremes by age group. We analysed data on daily mortality due to natural causes (ICD-10: A00-R99) in the city of Madrid across the period 2001-2009 and calculated the impact of extreme temperatures on mortality using Poisson regression models for specific age groups. The groups of age selected coinciding with the pre-existing age-groups analyzed in previous papers. For heat waves the groups of age used were: <10 years, 10-17 years, 18-44 years, 45-64 years, 65-74 years and over-75 years. For cold waves the groups of age used were: <1 year; 1-5 years, 6-17 years, 18-44 years, 45-64 years, 65-74 years and over-75 years. <1, 1-17, 18-44, 45-66, 65-74 and over-75 years. We controlled for confounding variables, such as air pollution, noise, influenza, pollen, pressure and relative humidity, trend of the series, as well as seasonalities and autoregressive components of the series. The results of these models were compared to those obtained for the same city during the period 1986-1997 and published in different studies. Our results show a lightly reduction in the effects of heat, especially in the over-45-year age group. In the case of cold, the behaviour pattern was the opposite, with an increase in its effect. Heat adaptation and socio-economic and public-health prevention and action measures may be behind this amelioration in the effects of heat, whereas the absence of such actions in respect of low temperatures may account for the increase in the effects of cold on mortality. From a public health point of view, the implementation of cold wave prevention plans covering all age groups is thus called for.

Changes in cause-specific mortality during heat waves in central Spain, 1975-2008

The relationship between heat waves and mortality has been widely described, but there are few studies using long daily data on specific-cause mortality. This study is undertaken in central Spain and analysing natural causes, circulatory and respiratory causes of mortality from 1975 to 2008. Time-series analysis was performed using ARIMA models, including data on specific-cause mortality and maximum and mean daily temperature and mean daily air pressure. The length of heat waves and their chronological number were analysed. Data were stratified in three decadal stages: 1975-1985, 1986-1996 and 1997-2008. Heat-related mortality was triggered by a threshold temperature of 37 °C. For each degree that the daily maximum temperature exceeded 37 °C, the percentage increase in mortality due to circulatory causes was 19.3 % (17.3-21.3) in 1975-1985, 30.3 % (28.3-32.3) in 1986-1996 and 7.3 % (6.2-8.4) in 1997-2008. The increase in respiratory cause ranged from 12.4 % (7.8-17.0) in the first period, to 16.3 % (14.1-18.4) in the second and 13.7 % (11.5-15.9) in the last. Each day of heat-wave duration explained 5.3 % (2.6-8.0) increase in respiratory mortality in the first period and 2.3 % (1.6-3.0) in the last. Decadal scale differences exist for specific-causes mortality induced by extreme heat. The impact on heat-related mortality by natural and circulatory causes increases between the first and the second period and falls significantly in the last. For respiratory causes, the increase is no reduced in the last period. These results are of particular importance for the estimation of future impacts of climate change on health.

Source apportionment of synchronously size segregated fine and coarse particulate matter, using an improved three-way factor analysis model

Samples of PM₁₀ and PM₂.₅ were synchronously collected from a megacity in China (Chengdu) during the 2011 sampling campaign and then analyzed by an improved three-way factor analysis method based on ME2 (multilinear engine 2), to investigate the contributions and size distributions of the source categories for size segregated particulate matter (PM). Firstly, the synthetic test was performed to evaluate the accuracy of the improved three-way model. The same five source categories with slightly different source profiles were caught. The low AAE (average absolute error) values between the estimated and the synthetic source contributions (<15%) and the approachable estimated PM₂.₅/PM₁₀ ratios with the simulated ratios might indicate that the results of the improved three-way factor analysis might be satisfactory. Then, for the ambient PM samples, the mean levels were 206.65 ± 69.90 μg/m(3) (PM₁₀) and 130.47 ± 43.67 μg/m(3) (PM₂.₅). The average ratio of PM₂.₅/PM₁₀ was 0.63. PM₁₀ and PM₂.₅ in Chengdu were influenced by the same source categories and their percentage contributions were in the same order: crustal dust & coal combustion presented the highest percentage contributions, accounting for 58.20% (PM₁₀) and 53.73% (PM2.5); followed by vehicle exhaust & secondary organic carbon (18.45% for PM₁₀ and 21.63% for PM₂.₅), secondary sulfate and nitrate (17.06% for PM₁₀ and 20.91% for PM₂.₅) and cement dust (6.30% for PM₁₀ and 3.73% for PM₂.₅). The source profiles and contributions presented slightly different distributions for PM₁₀ and PM₂.₅, which could better reflect the actual situation. The findings based on the improved three-way factor analysis method may provide clear and deep insights into the sources of synchronously size-resolved PM.

Ambient particulate matter in a central urban area of Seoul, Korea

The concentrations of PM2.5 and PM10 were monitored at a central urban area of Yongsan (YS), Seoul, Korea during 2013. The daily average concentrations of both PM2.5 and PM10 fractions, were 26.6±12.6 and 45.0±20.4 μg m(-3), respectively. The observed PM2.5 concentration slightly exceeded the annual standard value (25 μg m(-3)) set by the Korean Ministry of Environment (KMOE), while that of PM10 was slightly lower than its guideline value (50 μg m(-3)). Comparison of the monthly mean values (μg m(-3)) of both PM fractions showed maximum concentrations in January (PM2.5: 36.9 and PM10: 59.7) and minimum concentrations in September (PM10: 28.1) and October (PM2.5: 14.9). The existence of strong correlations between the concentrations of PM and some gaseous pollutants (e.g., CO, SO2, and NOx) indicated the commonality of contributing source processes, such as traffic and industrial emissions. The results of a back-trajectory (BT) analysis also suggests that the PM pollution in the study area is likely to have been affected by many sources such as Asian dust, volcanic emissions, and industrial activities in the surrounding countries (China, Russia, and Japan).

Decomposing the profile of PM in two low polluted German cities--mapping of air mass residence time, focusing on potential long range transport impacts

This paper aims to decompose the profile of particulates in Karlsruhe and Potsdam (Germany), focusing on the localization of PM potential transboundary sources. An air mass cluster analysis was implemented, followed by a study of air mass residence time on a grid of a 0.5° × 0.5° resolution. Particulate/gaseous daily air pollution and meteorological data were used to indicate PM local sources. Four Principal Component Analysis (PCA) components were produced: traffic, photochemical, industrial/domestic and particulate. PM2.5/PM10 ratio seasonal trends, indicated production of PMCOARSE (PM10-PM2.5) from secondary sources in Potsdam during warm period (WP). The residing areas of incoming slow moving air masses are potential transboundary PM sources. For Karlsruhe those areas were mainly around the city. An air mass residence time secondary peak was observed over Stuttgart. For Potsdam, areas with increased dwelling time of the arriving air parcels were detected particularly above E/SE Germany.

Associations between fine and coarse particles and mortality in Mediterranean cities: results from the MED-PARTICLES project

BACKGROUND

Few studies have investigated the independent health effects of different size fractions of particulate matter (PM) in multiple locations, especially in Europe.

OBJECTIVES

We estimated the short-term effects of PM with aerodynamic diameter ≤ 10 μm (PM10), ≤ 2.5 μm (PM2.5), and between 2.5 and 10 μm (PM2.5-10) on all-cause, cardiovascular, and respiratory mortality in 10 European Mediterranean metropolitan areas within the MED-PARTICLES project.

METHODS

We analyzed data from each city using Poisson regression models, and combined city-specific estimates to derive overall effect estimates. We evaluated the sensitivity of our estimates to co-pollutant exposures and city-specific model choice, and investigated effect modification by age, sex, and season. We applied distributed lag and threshold models to investigate temporal patterns of associations.

RESULTS

A 10-μg/m3 increase in PM2.5 was associated with a 0.55% (95% CI: 0.27, 0.84%) increase in all-cause mortality (0-1 day cumulative lag), and a 1.91% increase (95% CI: 0.71, 3.12%) in respiratory mortality (0-5 day lag). In general, associations were stronger for cardiovascular and respiratory mortality than all-cause mortality, during warm versus cold months, and among those ≥ 75 versus < 75 years of age. Associations with PM2.5-10 were positive but not statistically significant in most analyses, whereas associations with PM10 seemed to be driven by PM2.5.

CONCLUSIONS

We found evidence of adverse effects of PM2.5 on mortality outcomes in the European Mediterranean region. Associations with PM2.5-10 were positive but smaller in magnitude. Associations were stronger for respiratory mortality when cumulative exposures were lagged over 0-5 days, and were modified by season and age.

IMPACTS OF AMBIENT TEMPERATURE AND PRESSURE ON PM2.5 EMISSION PROFILES OF LIGHT-DUTY DIESEL VEHICLES

The impact of the environmental factors on the emissions of particulate matter (PM) number, size distribution and mass size distribution from diesel passenger cars was evaluated. Particle measurements from five modern light-duty diesel vehicles (LDDV) were performed in June and November 2011. Commercial low sulfur diesel fuel (less than 50 ppm) was used during the testing of these vehicles which were not equipped with after-treatment devices. The dynamometer test was based on the Economic Commission of Europe (ECE) 15 cycles. The results indicate that PM2.5 emissions from LDDV are significantly affected by ambient temperature and pressure. A comparison of the emissions concentration of PM2.5 in these two different months showed that the number concentration in June was (3.8 ± 0.69) × 107 cm-3 and (2.5 ± 0.66) × 107 cm-3 in November. The PM concentration of about 30 nm diameter was 25 ± 6% of the total emissions in November while only 14 ± 3% of total emissions in June. In the 60 nm to 2.5 μm test range, November data shows less of a contribution for number than data from June testing. The concentration of mass emissions in June was (325 ± 44) mg/m3 and (92 ± 30) mg/m3 in November. The contribution of the number of PM particles in November testing is lower than testing in June by 34% and the mass concentration in November is 70% lower than that in June. With the decrease of ambient temperature and the increase of ambient pressure, both the oxygen concentration in cylinder and air–fuel ratio are increased, which caused lower particle number and mass emissions during November testing. The size distribution is also altered by these changes: the more efficient in-cylinder combustion resulted in a higher proportion of particles in the 30 nm and smaller range than for other particle sizes.

Effects of exposure to rice-crop residue burning smoke on pulmonary functions and oxygen saturation level of human beings in Patiala (India)

Pulmonary Function Tests (PFTs) like Force Vital Capacity (FVC), Force Expiratory Volume in one second (FEV₁), Peak Expiratory Flow (PEF) and Force Expiratory Flow between 25 and 75% of FVC (FEF(25-75%)) and Oxygen Saturation (SpO₂) level of 50 healthy inhabitants with respect to rice crop residue burning were investigated for three rice cultivation periods from 2007 to 2009. The subjects were residents of five sampling sites selected in Patiala city. Concentration of Suspended Particulate Matter (SPM), Sulfur dioxide (SO₂), Nitrogen dioxide (NO₂) and Particulate Matter (PM) of size less than 10 and 2.5 μm (PM₁₀ and PM₂.₅) were measured by using High Volume Sampler (HVS) and Cascade Anderson Impactor. Results show that rice crop residue burning increases the pollution level in the ambient air, and PFTs undergo a significant decrease in their respective values. No significant change was seen in SpO₂ level during rice crop residue burning. In 2008, an increase of 10 μg m⁻³ in PM₂.₅, PM₁₀, SPM and NO₂ was associated significantly with decrease in FVC in percentages predicted -1.541, -1.002, -1.178, -0.232%, respectively. The decrease in air quality due to open rice crop residue burning has sub acute effect on pulmonary functions of healthy subjects and that SO₂ and NO₂ have less adverse effects on pulmonary functions than with different size Particulate Matter.

Influence of local factors in the relationship between mortality and heat waves: Castile-La Mancha (1975-2003)

INTRODUCTION

All the climate-change studies undertaken to date agree that one of the principal consequences of this phenomenon is the increase in heat waves, which, without exception, are linked to marked rises in mortality. The characteristics that modulate and determine the relationship between high temperatures and health must therefore be ascertained in the greatest possible detail, so that really effective prevention plans can be designed to address temperature extremes.

METHODS

We examined the effect of heat waves on daily non-accidental-cause mortality across all age groups in the Castile-La Mancha region (Spain) from 1975 to 2003. Quantitative analyses were performed using autoregressive integrated moving average (ARIMA) models, with other covariates, such as pressure trends, relative humidity, and duration and chronological number of heat waves.

RESULTS

Mortality increased significantly with respect to the mean, when temperatures exceeded the designated provincial thresholds in Castile-La Mancha. For each degree centigrade that temperatures exceeded these thresholds, the percentage increase in mortality amounted to increases of approximately 12% over the daily mean, albeit with clear provincial variations. The longest heat waves were associated with daily mortality, with those at the end of summer causing the lowest mortality. Meteorological situations most closely associated with increases in mortality were cyclonic conditions accompanied by low humidity.

CONCLUSIONS

Spatio-temporal variability in the temperature-mortality relationship must be studied in order to enable really effective heat-wave prevention plans to be drawn up. The influence of variables, such as heat-wave duration or time of appearance, is important in the total increase in mortality during temperature extremes. Since parameters, such as humidity or pressure trends, can play very different roles in different geographical settings, they should be analysed separately from temperature.

Particulate air pollution and short-term mortality due to specific causes among the elderly in Madrid (Spain): seasonal differences

A time-series study was conducted to ascertain the short-term effects of different-sized airborne particulate matter (PM) on daily respiratory and cardiovascular cause-specific mortality in winter and summer, among subjects aged over 75 years in Madrid. Poisson regression was used to analyse the time-series, in which the dependent variable was daily mortality due to different specific respiratory and circulatory causes, and the principal independent variables were daily mean PM10, PM2.5 and PM10-2.5 concentrations; other variables: other air pollutants (chemicals, biotic and acoustic), influenza, trend, seasonality and autocorrelation of the series. The results indicated an association between coarser PM fractions (PM10 and PM10-2.5) and respiratory-specific mortality on the one hand, and between PM2.5 and cardiovascular-specific mortality on the other. While the risk of mortality due to exposure to particulate matter was greater in summer than in winter, this difference was statistically significant solely for total organic-cause mortality.

Short-term impact of particulate matter (PM(2.5)) on respiratory mortality in Madrid

OBJECTIVES

This paper sought to quantify the particulate matter (PM(2.5)) pollutant's impact on short-term daily respiratory-cause mortality in the city of Madrid.

METHODS

As our dependent variable, we took daily mortality registered in Madrid from 1 January 2003 to 31 December 2005, attributed to all diseases of the respiratory system as classified under heads J00-J99 of the ICD 10 and broken down as follows: J12-J18, pneumonia; J40-J44, chronic diseases of the respiratory system except asthma; J45-J46, asthma; and J96, respiratory failure.

RESULTS

The relative risk (RR) for daily overall respiratory mortality was RR 1.0281 (1.0043-1.0520), with a proportional attributable risk (PAR) of 2.74%. This effect occurred in lag 1; respiratory failure, RR 1.0816 (1.0119-1.1512) and PAR 7.54% at lag 5; and pneumonia, RR 1.0438 (1.0001-1.0875) and PAR 4.19% at lag 6.

CONCLUSIONS

Our results reflect the association that exists between PM(2.5) concentrations and daily respiratory-cause mortality.

Health impact assessment of a reduction in ambient PM(2.5) levels in Spain

BACKGROUND

Health effects linked to exposure to high air pollutant levels have been described in depth, and many recent epidemiologic studies have also consistently reported positive associations between exposure to air pollutants at low concentrations (particularly PM(2.5)) and adverse health outcomes.

OBJECTIVE

To estimate the number of avoidable deaths associated with reducing PM(2.5) levels in Spain.

MATERIALS AND METHODS

For exposure assessment, we used the US Environmental Protection Agency's Community Multiscale Air Quality model to simulate air pollution levels with a spatial resolution of 18×18 km(2). Two different scenarios were compared, namely, a baseline 2004 scenario based on Spain's National Emissions Inventory and a projected 2011 scenario in which a reduction in PM(2.5) was estimated on the basis of the benefits that might be attained if specific air quality policies were implemented. Using an 18×18 km(2) grid, air pollution data were estimated for the entire Iberian Peninsula, the Balearic Islands, Ceuta and Melilla. For these strata, crude all-cause mortality rates (ICD-10: A00-Y98) were then calculated for the over-30 and 25-74 age groups, taking into account the 2004 population figures corresponding to these same age groups, selected in accordance with the concentration-response functions (Pope CA 3rd, Burnett RT, Thun MJ, Calle EE, Krewski D, Ito K et al. Lung cancer, cardiopulmonary mortality, and long-term exposure to fine particulate air pollution. JAMA 2002; 287:1132-41; Laden F, Schwartz J, Speizer FE, Dockery DW. Reduction in fine particulate air pollution and mortality: extended follow-up of the Harvard Six Cities study. Am J Respir Crit Care Med 2006; 173:667-72.). Health impacts were assessed using the Environmental Benefits Mapping and Analysis Program (BenMAP).

RESULTS

Air quality improvement was defined as an average annual reduction of 0.7 μg/m(3) in PM(2.5) levels. Using long-term health impact assessment analysis, we estimated that 1720 (673-2760) all-cause deaths (6 per 100,000 population) in the over-30 age group and 1450 (780-2108) all-cause deaths (5 per 100,000 population) in the 25-74 age group could be prevented annually.

CONCLUSIONS

The results showed the potential benefits in general mortality which could be expected if pollution control policies were successfully implemented by 2011. A specifically adapted BenMAP could be used as a tool for estimating health impacts associated with changes in air pollution in Spain.

Role of Saharan dust in the relationship between particulate matter and short-term daily mortality among the elderly in Madrid (Spain)

BACKGROUND

Saharan dust outbreaks are a common phenomenon in the Madrid atmosphere. The current Directive 2008/50 CE governing air quality in European cities, draws no distinction between which particulate matter (PM(10), PM(2.5) or PM(10-2.5)) would be the best indicator on days with/without Saharan dust intrusions. This study sought to identify the role played by Saharan dust in the relationship between particulate matter (PM(10), PM(2.5) and PM(10-2.5)) concentrations and daily mortality among the elderly in the city of Madrid.

METHODS

We conducted an ecological longitudinal time-series study on daily mortality among the over-75 age group, from 2003 to 2005. Poisson regression models were constructed for days with and without Saharan dust intrusions. The following causes of daily mortality were analysed: total organic causes except accidents (International Classification of Diseases-10th revision (ICD-10): A00-R99); circulatory causes (ICD-10: I00-I99); and respiratory causes (ICD-10: J00-J99). Daily mean PM(10), PM(2.5) and PM(10-2.5) levels were used as independent variables. Control variables were: other ambient pollutants (chemical, biotic and acoustic); trend; seasonalities; influenza epidemics; and autocorrelations between mortality series.

RESULTS

While daily mean PM(2.5) concentrations in Madrid displayed a significant statistical association with daily mortality for all the above causes on days without Saharan dust intrusions, this association was not in evidence for PM(10) or PM(10-2.5) in the multivariate models. The relative risks (RRs) obtained for an increase of 10 μg/m(3) in PM(2.5) concentrations were: 1.023 (1.010-1.036) for total organic causes; 1.033 (1.031-1.035) for circulatory causes; and 1.032 (1.004-1.059) for respiratory causes. On Saharan dust days, a significant statistical association was detected between PM(10) (though not PM(2.5) or PM(10-2.5)) and mortality for all 3 causes analysed, with RRs statistically similar to those reported for PM(2.5).

CONCLUSIONS

The best air quality indicators for evaluating the short-term health effects of particulate matter in Madrid are therefore PM(10) concentrations on days with, and PM(2.5) concentrations on days without Saharan dust outbreaks. This fact should be taken into account in a European Directive regulating ambient air quality in almost all countries in the Mediterranean area.

Short-term effect of fine particulate matter (PM 2.5) on daily mortality due to diseases of the circulatory system in Madrid (Spain)

INTRODUCTION

Owing to their small size, fine particles, i.e., those having a diameter ≤ 2.5 μm (PM(2.5)), have a high alveolar penetration capacity, thereby triggering a local inflammatory process with circulatory repercussion. Despite being linked to respiratory and cardiovascular morbidities, there is limited evidence of an association between this type of particulate matter and short-term increases in mortality.

OBJECTIVE

The aim of this study was to analyse and quantify the short-term impact of PM(2.5) on daily mortality due to diseases of the circulatory system, registered in Madrid from 1 January 2003 to 31 December 2005.

METHODS

An ecological longitudinal time-series study was conducted, with risks being quantified by means of Poisson regression models. As a dependent variable, we took daily mortality registered in Madrid from 1 January 2003 to 31 December 2005, attributed to all diseases of the circulatory system as classified under heads I00-I99 of the International Classification of Diseases-10th revision (ICD-10) and broken down as follows: I21, acute myocardial infarction (AMI); I20, I22-I25, other ischemic heart diseases; and I60-I69, cerebrovascular diseases. The independent variable was daily mean PM(2.5) concentration. The other variables controlled for were: chemical pollution (PM(10), O(3), SO(2), NO(2) and NO(x)); acoustic and biotic pollution; influenza; minimum and maximum temperatures; seasonalities; trend; and autocorrelation of the series.

RESULTS

A linear relationship was observed between PM(2.5) levels and mortality due to diseases of the circulatory system. For every increase of 10 μg/m(3) in daily mean PM(2.5) concentration, the relative risks (RR) were as follows: for overall circulatory mortality, associations were established at lags 2 and 6, with RR of 1.022 (1.005-1.039) and 1.025 (1.007-1.043) respectively; and for AMI mortality, there was an association at lag 6, with an RR of 1.066 (1.032-1.100). The corresponding attributable risks percent (AR%) were 2.16%, 2.47% and 6.21% respectively. No statistically significant association was found with other ischemic heart diseases or with cerebrovascular diseases.

CONCLUSION

PM(2.5) concentrations are an important risk factor for daily circulatory-cause mortality in Madrid. From a public health point of view, the planning and implementation of specific measures targeted at reducing these levels constitute a pressing need.

Cement dust exposure and acute lung function: a cross shift study

Background

Few studies have been carried out on acute effects of cement dust exposure. This study is conducted to investigate the associations between current "total" dust exposure and acute respiratory symptoms and respiratory function among cement factory workers.

Methods

A combined cross-sectional and cross-shift study was conducted in Dire Dawa cement factory in Ethiopia. 40 exposed production workers from the crusher and packing sections and 20 controls from the guards were included. Personal "total" dust was measured in the workers' breathing zone and peak expiratory flow (PEF) was measured for all selected workers before and after the shift. When the day shift ended, the acute respiratory symptoms experienced were scored and recorded on a five-point Likert scale using a modified respiratory symptom score questionnaire.

Results

The highest geometric mean dust exposure was found in the crusher section (38.6 mg/m³) followed by the packing section (18.5 mg/m³) and the guards (0.4 mg/m³). The highest prevalence of respiratory symptoms for the high exposed workers was stuffy nose (85%) followed by shortness of breath (47%) and "sneezing" (45%). PEF decreased significantly across the shift in the high exposed group. Multiple linear regression showed a significant negative association between the percentage cross-shift change in PEF and total dust exposure. The number of years of work in high-exposure sections and current smoking were also associated with cross-shift decrease in PEF.

Conclusions

Total cement dust exposure was related to acute respiratory symptoms and acute ventilatory effects. Implementing measures to control dust and providing adequate personal respiratory protective equipment for the production workers are highly recommended.