Air pollution and mortality in Chile: susceptibility among the elderly

Ambient air pollution exposure and COVID-19 related hospitalizations in Santiago, Chile

Morbidity and mortality from several diseases are increased on days of higher ambient air pollution. We carried out a daily time-series analysis with distributive lags to study the influence of short-term air pollution exposure on COVID-19 related hospitalization in Santiago, Chile between March 16 and August 31, 2020. Analyses were adjusted for temporal trends, ambient temperature, and relative humidity, and stratified by age and sex. 26,579 COVID-19 hospitalizations were recorded of which 24,501 were laboratory confirmed. The cumulative percent change in hospitalizations (95% confidence intervals) for an interquartile range increase in air pollutants were: 1.1 (0.2, 2.0) for carbon monoxide (CO), 0.30 (0.0, 0.50) for nitrogen dioxide (NO2), and 2.7 (1.9, 3.0) for particulate matter of diameter ≤ 2.5 microns (PM2.5). Associations with ozone (O3), particulate matter of diameter ≤ 10 microns (PM10) and sulfur dioxide (SO2) were not significant. The observed effect of PM2.5 was significantly greater for females and for those individuals ≥ 65 years old. This study provides evidence that daily increases in air pollution, especially PM2.5, result in a higher observed risk of hospitalization from COVID-19. Females and the elderly may be disproportionately affected.

An overview of air pollution research in Chile: Bibliometric analysis and scoping review, challenger and future directions

This study provides a comprehensive overview and bibliometric analysis of air pollution research in Chile from 1980 to 2022. The analysis reveals a significant increase in scientific production, a 9.2 annual growth rate, and an H-index of 60. The research spans 33 countries and is influenced by environmental sciences, meteorology, and atmospheric sciences journals. The top ten authors account for 33.49 % of all publications, with local institutions contributing more than 35 %. The University of Chile and the Pontifical Catholic University of Chile are significant contributors. The most cited articles focus on health impacts and various pollutant sources, emphasizing air pollution as a critical public health concern. The study also emphasizes environmental science, meteorology, and atmospheric science, focusing on topics such as air pollution and health, pollutants, models, sources and chemistry, and social sciences. The findings are affirmed through rigorous discussion and review, providing a roadmap for future research, guiding decision-making processes, and expanding the knowledge frontier in the field.

Chronic exposure to fine particles (PM2.5) and mortality: Evidence from Chile

Many Chilean cities suffer from high air pollution from industrial, mobile, and residential wood-burning sources. Several studies have linked PM2.5 air pollution exposure to higher mortality risk from cardiovascular, pulmonary, and lung cancer causes. In recent years, Chile has developed an extensive air pollution monitoring network to enforce air quality standards for PM2.5, allowing the study of the medium-term association between PM2.5 and mortality.

Methods

A negative binomial regression model was used to study the association between 3-year average PM2.5 concentrations and age-adjusted mortality rates for 105 of the 345 municipalities in Chile. Models were fitted for all (ICD10 A to Q codes), cardiopulmonary (I and J), cardiovascular (I), pulmonary (J), cancer (C), and lung cancer (C33-C34) causes; controlling for meteorological, socioeconomic, and demographic characteristics.

Results

A significant association of PM2.5 exposure with cardiopulmonary (relative risk for 10 µg/m3 PM2.5: 1.06; 95% confidence interval = 1.00, 1.13) and pulmonary (1.11; 1.02, 1.20) age-adjusted mortality rates was found. Cardiovascular (1.06; 0.99, 1.13) and all causes (1.02; 0.98, 1.07) were positive, but not significant. No significant association was found between cancer and lung cancer. The positive associations remained even when controlling for multiple confounding factors, model specifications, and when considering different methods for exposure characterization. These estimates are in line with results from cohort studies from the United States and European studies.

Conclusion

Three-year average PM2.5 exposure is positively associated with the age-adjusted mortality rate for cardiopulmonary and cardiovascular causes in Chile. This provides evidence of the medium-term exposure effect of fine particles on long-term mortality rates.

Effect of short-term exposure to ambient air pollutants on non-accidental mortality in emergency department visits: a time-series study

Objectives

Exposure to air pollution has been linked to an increased risk of premature mortality. However, the acute effects of air pollution on the risk of non-accidental mortality have not been extensively researched in developing countries, and the findings thus far have been inconsistent. Therefore, this study aimed to examine the association between short-term exposure to six pollutants (PM_2.5, PM₁₀, SO₂, NO₂, O₃, and CO) and non-accidental mortality in Beijing, China.

Methods

Daily data on non-accidental deaths were gathered from 1 January 2017 to 31 December 2018. Air pollution data for the same period were collected from 35 fixed-site air quality monitoring stations in Beijing. Generalized additive models (GAM) based on Poisson regression were used to investigate the association between non-accidental mortality in emergency department visits and the daily average levels of air pollutants.

Results

There were 8,676 non-accidental deaths recorded during 2017-2018. After sensitivity analysis, short-term exposure to air pollutants, particularly gaseous pollutants, was linked to non-accidental mortality. Specifically, for every 10 μg/m³ increase (5 μg/m³ in SO₂, 0.5 mg/m³ in CO) of SO₂ (lag 04), NO₂ (lag 04), O₃ (lag 05), and CO (lag 04), the relative risk (RR) values were 1.054 (95% CI: 1.009, 1.100), 1.038 (95% CI: 1.013, 1.063), 1.032 (95% CI: 1.011, 1.054), and 1.034 (95% CI: 1.004, 1.066), respectively. In terms of causes of death, short-term exposure to NO₂, SO₂, and O₃ increased the risk of circulatory mortality. Further stratified analysis revealed that the stronger associations were presented in females for O₃ while in males for CO. People aged 65 and over were strongly associated with ambient air pollution.

Conclusions

Our study showed that ambient air pollutants were associated with non-accidental mortality. Our findings suggested that efforts to control gaseous pollution should be stepped up, and vulnerable groups should be the focus of health protection education.

The impact of air pollution on physical disability in a middle-aged and older Chinese population using regression discontinuity design

Emerging evidence has shown the association between ambient air pollution exposure and comorbid chronic diseases, which can subsequently impair physical function. However, less is known about the causal and contextual effect of air pollution on physical disability. Using data from the China Health and Retirement Longitudinal Study (CHARLS), this study employs a geographical regression discontinuity design based on the Huai River Policy to estimate the impact of ambient air pollution on physical disability in activities of daily living (ADL) in China. We find that a 10 μg/m³ increase in particulate matter [particulate matter smaller than 10 μm (PM₁₀)] leads to a 5.4% increase in the incidence of physical disability among middle-aged and older adults. This result is robust to using alternative measurement of key variables, different bandwidths and polynomial functions, and adjustment for a set of sociodemographic covariates. Stroke might be one of the potential pathological pathways linking air pollution and physical disability, with a 10 μg/m³ increase in PM₁₀ leading to a 4.7% increase in the incidence of stroke. In heterogeneity analyses, we find that older adults, males, urban residents, and people with lower socioeconomic status are more vulnerable to air pollution. These results contribute to the limited evidence on the causal and contextual effect of air pollution on physical health, and further provide policy implications for air quality control and health protection for vulnerable populations.

Daily Mortality in Different Age Groups Associated with Exposure to Particles, Nitrogen Dioxide and Ozone in Two Northern European Capitals: Stockholm and Tallinn

Although the association between air pollution and mortality is well established, less is known about the effects in different age groups. This study analyzes the short-term associations between mortality in different age groups (0–14 years of age, 15–64 years of age, and 65+ years of age) and a number of air pollutants in two relatively clean northern European capitals: Stockholm and Tallinn. The concentrations in PM10 (particles with an aerodynamic diameter smaller than or equal to 10 µm), PM2.5–10 (coarse particles), PM2.5 (particles with an aerodynamic diameter smaller than or equal to 2.5 µm), BC (black carbon), PNC4 (particle number count of particles larger than or equal to 4 nm), NO2 (nitrogen dioxide), and O3 (ozone) were measured during the period of 2000–2016 in Stockholm and 2001–2018 in Tallinn (except for BC and PNC4 which were only measured in Stockholm). The excess risks in daily mortality associated with an interquartile range (IQR) increase in the measured air pollutants were calculated in both single- and multi-pollutant models for lag01 and lag02 (average concentration during the same and the previous day, and the same and the previous two days, respectively) using a quasi-Poisson regression model with a logistic link function. In general, the calculated excess risks per IQR increase were highest in the age group 0–14 years of age in both Stockholm and Tallinn. However, in Stockholm, a statistically significant effect was shown for PM2.5–10, and in Tallinn for O3. In the oldest age group (65+), statistically significant effects were shown for both PM2.5–10, PM10, and O3 in Stockholm, and for O3 in Tallinn.

Socioeconomic development role in hospitalization related to air pollution and meteorology: A study case in southern Brazil

Air pollution is one of the foremost environmental threats to human health. However, the meteorological and social factors that lead to respiratory and cardiovascular diseases have not been fully elucidated. In this study, we use Principal Component Analysis and Generalized Linear Model (PCA-GLM) to investigate the combined effect of socioeconomic development and air pollution on cardiorespiratory hospitalization in southern Brazil. This region has the highest rates of hospitalization by cardiorespiratory diseases in the country. We analyze three main sources of data: (i) air pollutants density from TROPOMI/Sentinel-5p satellite; (ii) temperature, humidity, and planetary boundary layer height (PBLH) modeled with the Weather Research Forecast model; and (iii) hospitalization by cardiorespiratory diseases obtained from the Brazilian National Health System. We estimate the Relative Risk (RR) using the PCA-GLM coefficients and interquartile variations of air pollutants density and meteorological parameters. Our results show that the population living in colder and drier municipalities is more prone to cardiorespiratory hospitalization. Regarding respiratory hospitalization, municipalities with lower socioeconomic development are more sensitive to meteorology and pollution variability than highly developed ones. In less developed municipalities, we observe the highest rates of cardiorespiratory hospitalization even if air pollution is low, which we interpret in terms of higher vulnerability. The RR analysis suggests that air pollution is an important environmental risk to cardiovascular diseases and respiratory diseases is more sensitive to air pollution and meteorology than cardiovascular ones. Our findings corroborate the mounting evidence that social vulnerability is a significant factor affecting the increase of cardiorespiratory hospitalization in the world.

Relationship between Wildfire Smoke and Children’s Respiratory Health in the Metropolitan Cities of Central-Chile

Wildfire causes multiple problems for people living in cities. One of them is the deterioration of air quality as a result of wildfire smoke. This smoke can consequently have effects on human health. The present study aims to characterize the relationship between the occurrence of wildfires in central Chile and the effects on children’s respiratory health. Public databases provided the number of emergency care visits, wildfires, and concentration of air pollutants, demographics and meteorological variables for the regions of Santiago and Valparaiso from 2010 to 2013. Time series analysis was used monthly on health care visits to determine the relative health risk in children when in the presence of additional wildfires. Significant health risks were observed in Santiago for children younger than 1-year-old of bronchitis (RR 1.007, CI 95% 1.007–1.008; chronic lower respiratory diseases (RR 1.012, CI 95% 1.012–1.013); and pneumonia (RR 1.026 CI 95% 1.026–1.027) and in children aged one to four years old (RR 1.016 CI 95% 1.015–1.016). A dose-response relationship was also observed for pneumonia, showing that it affects younger children particularly when there is an increase in the number of wildfires. In the Region of Valparaíso, wildfires did not significantly change the risk of respiratory illness, this could be due to favorable ventilation. Currently, Santiago has an urgent need for monitoring and the evaluation of the damage to children’s respiratory health, along with the development of comprehensive prevention strategies.

Air Pollution and Mortality in the Elderly in Kerman, Iran

Background: Today, air pollution is a major issue in the world, particularly in metropolitan areas. Objectives: Accordingly, this study aimed to investigate the relation between air pollution and mortality in the elderly in Kerman City. Methods: This ecological study was conducted using 2006 - 2013 mortality data inquired from the Deputy of Health of Kerman University of Medical Sciences. The data on cardiovascular and respiratory mortality, as well as death due to trauma, diabetes, and other diseases that happened in men and women aged 60 and higher were extracted. Air pollution data (CO, SO2, O3, NO, NO2, NOx, and PM10) for the same time frame were inquired from the Environmental Protection Agency of Kerman Province. Negative binomial regression was used to evaluate the relation between air pollutants and mortality using STATA13 software. Results: During the study period, a total of 14,793 deaths occurred in elderly men and women in Kerman City. Cardiovascular diseases were the leading cause of death. The results of multivariate analysis of air pollutants indicated that NO was directly and significantly related to the total number of deaths in the elderly, and increase in sulfur dioxide, ozone and NO was significantly related to increased mortality among elderly women. Carbon monoxide was significantly related to cardiovascular death of the elderly. But air pollutants did not show any significant effect on respiratory-, trauma-, and diabetes-related deaths. Conclusions: Our findings indicate that there is a significant relation between air pollution and mortality in the elderly. Accordingly, a warning system is suggested to reduce the elderly’s commuting on highly air polluted days.

The association between air pollution and COVID-19 related mortality in Santiago, Chile: A daily time series analysis

BACKGROUND

Exposure to ambient air pollution is a risk factor for morbidity and mortality from lung and heart disease.

RESEARCH QUESTION

Does short term exposure to ambient air pollution influence COVID-19 related mortality?

STUDY DESIGN AND METHODOLOGY

Using time series analyses we tested the association between daily changes in air pollution measured by stationary monitors in and around Santiago, Chile and deaths from laboratory confirmed or suspected COVID-19 between March 16 and August 31, 2020. Results were adjusted for temporal trends, temperature and humidity, and stratified by age and sex.

RESULTS

There were 10,069 COVID-19 related deaths of which 7659 were laboratory confirmed. Using distributed lags, the cumulative relative risk (RR) (95% CI) of mortality for an interquartile range (IQR) increase in CO, NO₂ and PM_2.5 were 1.061 (1.033-1.089), 1.067 (1.023-1.103) and 1.058 (1.034-1.082), respectively There were no significant differences in RR by sex.. In those at least 85 years old, an IQR increase in NO₂ was associated with a 12.7% (95% CI 4.2-22.2) increase in daily mortality.

CONCLUSION

This study provides evidence that daily increases in air pollution increase the risk of dying from COVID-19, especially in the elderly.

The association between air pollution and hospitalization for patients with systemic lupus erythematosus in Chile: A daily time series analysis

Genetic and environmental factors are thought to influence the activity of systemic lupus erythematosus (SLE), but relatively little is known about the effects of ambient air pollution. Using pollution data from air monitoring stations in the urban centers in Santiago Chile, along with daily patient hospitalization data from 2001 to 2012, an association between ambient air pollution and daily hospital admissions for SLE was tested using generalized linear models. Averaged over all regions pollutant mean 24 h concentrations were: 0.96 ppm carbon monoxide (CO), 64 ppb ozone (O₃), 43 ppb nitrogen dioxide (NO₂), 9 ppb sulphur dioxide (SO₂), 29 μg/m³ particulate matter ≤ 2.5 μm in mean aerodynamic diameter (PM_2.5), and 67 μg/m³ particulate matter ≤ 10 μm in diameter (PM₁₀). The relative risk estimates in single pollutant models for an interquartile range (IQR) increase in pollutant were: RR = 1.34 (95% CI: 1.06-1.83) for SO₂, RR = 1.60 (95% CI: 1.15-2.24) for CO, and RR = 1.41 (95% CI: 1.14-1.86) for PM_2.5. In two-pollutant models, the significance of SO₂ and PM_2.5 persisted despite adjustments for each of the other measured pollutants. These findings suggest that acute increases in air pollution increase the risk of hospitalization with a primary diagnosis of SLE.

The Association Between Air Pollution and Hospitalization of Patients With Idiopathic Pulmonary Fibrosis in Chile: A Daily Time Series Analysis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) causes progressive dyspnea, hypoxemia, and death within a few years. Little is known about the effect of air pollution on disease exacerbations.

RESEARCH QUESTION

Are acute increases in air pollution a risk factor for hospitalization of patients with a primary diagnosis of IPF.

STUDY DESIGN AND METHODS

Hospital admissions for IPF are coded J84.1 by the International Classification of Disease, 10th Revision. Using ambient air pollution and climate data from seven air monitoring stations distributed in the seven urban centers in Santiago, Chile, along with daily patient hospitalization data from 2001 to 2012, a linear association between daily ambient air pollution and daily J84.1 hospital admissions was tested using generalized linear models.

RESULTS

Average pollutant levels for all regions were as follows: carbon monoxide was 0.96 ppm, ozone was 64 ppb, nitrogen dioxide (NO₂) was 43 ppb, sulfur dioxide was 9 ppb, particulate matter < 2.5 μm in diameter was 29 μg/m³ and particulate matter < 10 μm in diameter (PM₁₀) was 67 μg/m³. For the combined Santiago area, relative risk estimates of J84.1 hospitalizations for all pollutants (except ozone), adjusted for age, sex, and weather were statistically significant. In the two-pollutant models, the significance of NO₂ and PM₁₀ persisted despite adjustments for each of the other measured pollutants.

INTERPRETATION

Our findings suggest that acute increases in air pollution are a risk factor for hospitalization of patients with a primary diagnosis of IPF.

Elderly Mortality and Exposure to Fine Particulate Matter and Ozone

BACKGROUND

The effects on particulate matter (PM) and ozone on health are being reported by a number of studies. The effects of these air pollutants are likely to be stronger in the elderly population, but studies in this regard are scarce. The purpose of this study was to study the effects of PM ≤ 2.5 μ and ozone on chronic health effects of the elderly population.

METHODS

In order to analyze the health status of the elderly population, National Statistical Office Mortality records were used. In this study, we calculated the number of deaths in Seoul of people who were 60 years or older between 2002 and 2012. The current study analyzed each disorder separately and the lag effect. PM and ozone were analyzed using the single exposure model, as well as the adjusted multi exposure model.

RESULTS

In the single exposure analysis with PM2.5 as the exposure variable, with the increase of 10 μ/m³, the number of deaths increased by 1.0039 fold, and vascular disease 1.0053 fold. In the multi exposure model adjusting for ozone, the number of deaths increased by 1.0037 fold, and vascular disease 1.0049 fold. In the single exposure analysis with ozone as the exposure variable, with the increase of 10 ppb, the number of deaths increased by 1.0038 fold, and in the multi exposure model adjusting for PM2.5, the number of deaths increased by 1.0027 fold. These results differed depending on the period or season. There was a 5-day lag effect between PM2.5 and deaths in the multi exposure model, and 1.0028 fold when adjusted for ozone. There was a 1-day lag effect in single exposure models with ozone as the main variable, and 1.0027 fold increase in deaths.

CONCLUSION

In our study, an increase in the number of deaths in the elderly population in accordance with the increase in the PM2.5 and ozone was found. The association found in our study could also influence socioeconomic burden. Future studies need to be performed in regards to younger population, as well as other air pollutants.

Particulate air pollution on cardiovascular mortality in the tropics: impact on the elderly

BACKGROUND

Air pollution has a significant health impact. Most data originate from temperate regions. We aim to study the health impact of air pollution, particularly among the elderly, in a tropical region.

METHODS

A daily time-series analysis was performed to estimate excess risk (ER) of various air pollutants on daily death counts amongst the general population in Singapore from 2001 to 2013. Air pollutants included particulate matters smaller than 10 μm, and 2.5 μm (PM₁₀, PM_2.5), carbon monoxide (CO), nitrogen dioxide (NO₂), ozone (O₃) and sulphur dioxide (SO₂). The studied outcomes were non-accidental and cardiovascular mortality. Single-day lag and distributed lag models were studied and adjusted for confounders.

RESULTS

In single-day lag models, a 10 μg/m³ increase in particulate matter was associated with significant increases in non-accidental (PM₁₀ ER: 0.627%; 95% confidence interval (CI): 0.260-0.995% and PM_2.5 ER: 0.660%; 95% CI: 0.204-1.118%) and cardiovascular mortality (PM₁₀ ER: 0.897; 95% CI: 0.283-1.516 and PM_2.5 ER: 0.883%; 95% CI: 0.121-1.621%). This was significant in the elderly ≥ 65 years but not in those < 65 years and were seen in the acute phase of lag 0-5 days. Effects by other pollutants were minimal. For cardiovascular mortality, the effects turned protective at a cumulative lag of 30 days in the elderly and could due to "harvesting".

CONCLUSIONS

These first contemporary population-based data from an equatorial country with tropical climate show that exposure to particulate air pollution was significantly associated with non-accidental mortality and cardiovascular mortality, especially in the elderly.

The association between human perceived heat and early-stage syphilis and its variance: Results from a case-report system

BACKGROUND

The relationship between temperature and syphilis is poorly understood despite clues and suggestions from previous studies. We examined the association between human perceived temperature (humidex) and the relative risk of early-stage syphilis in the most affected area of China, as well as its variance across social-economic status and age groups.

METHODS

Information regarding early-stage (primary and secondary) syphilis cases reported to the China Case Report System between 2005-2013 from Guangdong province was analyzed in this study. Weather data were obtained from the National Meteorological Information Center. Distributed lag nonlinear models were applied to assess the relationship between humidex and the relative risk of early-stage syphilis. Results were further stratified by social-economic status and age groups.

RESULTS

The relative risks of early-stage syphilis mainly increased with increased humidex, and were elevated when the humidex was around 30 or greater than 38. The humidex-RR association for the 15-40 age group was similar to the scenario pooled across the age groups, particularly in the Pearl-River Delta Region. The relative risk of syphilis in the elderly for the non-Pearl-River Delta Region did not show a clear change with humidex, whereas that in the Pearl-River Delta Region substantially increased, particularly when humidex was above 25.

CONCLUSIONS

Human perceived temperature was positively related to the relative risk of early-stage syphilis. People in the Pearl-River Delta Region tended to be more sensitive, with relative risk elevated at potential comfortable times or under excessively hot conditions. The vulnerability of the elderly in the Pearl-River Delta Region is concerning.

Anemia prevalence and hemoglobin levels are associated with long-term exposure to air pollution in an older population

BACKGROUND

Anemia, a highly prevalent disorder in elderly populations, is associated with numerous adverse health outcomes, including increased mortality, impaired functional status and cognitive disorders. Approximately two-thirds of anemia in American elderly is caused by chronic inflammation or is unexplained. A potential contributing factor may include air pollution exposures, which have been shown to increase systemic inflammation and affect erythropoiesis. Few studies, however, have investigated the associations of air pollution on hemoglobin levels and anemia.

METHODS

We used linear regression models and modified Poisson regression with robust error variance to examine the associations of particulate matter (PM_2.5) and nitrogen dioxide (NO₂) on hemoglobin concentrations and prevalence of anemia, respectively, among 4121 older Americans enrolled in the National Social Life, Health, and Aging Project. We estimated participant-specific exposures to PM_2.5 using spatio-temporal models, and to NO₂ using nearest measurements from Environmental Protection Agency's Air Quality System. Hemoglobin levels were measured for participants in each of two data collection waves from dried blood spots. Anemia was defined using World Health Organization hemoglobin-based criteria of <13 and <12g/dL for men and women, respectively. Models were adjusted for age, sex, smoking status, race, income, education, neighborhood socioeconomic status, region, urbanicity and medication use. Mediation by C-reactive protein (CRP), a marker of systemic inflammation, was also investigated.

RESULTS

An inter-quartile range (IQR, 3.9μg/m³) increase in the one-year moving average PM_2.5 was positively associated with anemia prevalence (prevalence ratio, or PR 1.33, 95% CI: 1.23, 1.45) and decreases in average hemoglobin of 0.81g/dL (p<0.001). Similarly, an IQR (9.6ppb) increase in NO₂ was associated with anemia prevalence (PR 1.43, 95% CI: 1.25, 1.63) and a decrease in average hemoglobin of 0.81g/dL (p<0.001). Strong dose-response relationships were identified for both pollutants. Mediation of the effect of PM_2.5 by CRP was also identified (p=0.007).

CONCLUSIONS/INTERPRETATIONS

Air pollution exposures were significantly associated with increased prevalence of anemia and decreased hemoglobin levels in a cohort of older Americans. If causal, these associations could indicate that chronic air pollution exposure is an important risk factor for anemia in older adults.

Comparison of Health Impact of Air Pollution Between China and Other Countries

Air pollution is the world's largest single environmental risk according to the World Health Organization (WHO), which caused around seven million deaths in 2012. Extensive epidemiological studies have been carried out worldwide to examine the health impacts of ambient air pollution, consistently demonstrating significant health impacts of ambient air pollution. Air pollution problem in China is especially serious; it has become the fourth biggest threat to the health of the Chinese people. In this review, we summarized existing literature, compared health impact of air pollution between China and other countries, and found substantial heterogeneity in the risk estimates of air pollution. The effect heterogeneities may be due to the differences in the characteristics of populations (e.g., the proportion of the elder population and people with preexisting diseases), exposure profile (e.g., air pollution concentrations and composition), and regional climate. Although the magnitude of relative risk estimates of air pollution is generally similar with that in other parts of the world, air pollution is one of China's most serious environmental health problems given the huge number of people exposed to high concentration levels of air pollution in China.

Chile Confronts its Environmental Health Future After 25 Years of Accelerated Growth

BACKGROUND

Chile has recently been reclassified by the World Bank from an upper-middle-income country to a high-income country. There has been great progress in the last 20 to 30 years in relation to air and water pollution in Chile. Yet after 25 years of unrestrained growth, there remain clear challenges posed by air and water pollution, as well as climate change.

OBJECTIVE

The aim of this study was to review environmental health in Chile.

METHODS

In late 2013, a 3-day workshop on environmental health was held in Santiago, Chile, bringing together researchers and government policymakers. As a follow-up to that workshop, here we review the progress made in environmental health in the past 20 to 30 years and discuss the challenges of the future. We focus on air and water pollution and climate change, which we believe are among the most important areas of environmental health in Chile.

RESULTS

Air pollution in some cities remains among the highest in the continent. Potable water is generally available, but weak state supervision has led to serious outbreaks of infectious disease and ongoing issues with arsenic exposure in some regions. Climate change modeling in Chile is quite sophisticated, and a number of the impacts of climate change can be reasonably predicted in terms of which areas of the country are most likely to be affected by increased temperature and decreased availability of water, as well as expansion of vector territory. Some health effects, including changes in vector-borne diseases and excess heat mortality, can be predicted. However, there has yet to be an integration of such research with government planning.

CONCLUSIONS

Although great progress has been made, currently there are a number of problems. We suspect that the Chilean experience in environmental health may be of some use for other Latin American countries with rapid economic development.

Assessing the impact of humidex on HFMD in Guangdong Province and its variability across social-economic status and age groups

Humidex is a meteorological index that combines the impacts of temperature and humidity, and is directly comparable with dry temperature in degrees Celsius. However, to date, no research has focused on the effect of humidex on hand, foot and mouth disease (HFMD). The current study was designed to address this research need. Case-based HFMD surveillance data and daily meteorological data collected between 2010 and 2012 was obtained from the China CDC and the National Meteorological Information Center, respectively. Distributed lag nonlinear models were applied to assess the impact of humidex on HFMD among children under 15 years oldin Guangdong, and its variability across social-economic status and age groups. We found that relative risk (RR) largely increased with humidex. Lag-specific and cumulative humidex-RR curves for children from the Pearl-River Delta Region as well as older children were more likely to show two-peak distribution patterns. One RR peak occurred at a humidex of between 15 and 20, and the other occurred between 30 and 35. This study provides a comprehensive picture of the impact of humidex on HFMD incidence in Guangdong Province. Results from the present study should be important in the development of area-and-age-targeted control programs.

Neurotoxicity induced by zinc oxide nanoparticles: age-related differences and interaction

This study mainly investigated the neurotoxicity induced by zinc oxide nanoparticle (ZnO NP) in different-aged mice and the interaction between age and ZnO NP exposure. Sixty adult and old male C57BL/6J mice were assigned to four groups based on a two-factor (age and ZnO NP exposure) design. Results showed that ZnO NPs (5.6 mg/kg, intraperitoneal) induced increased production of pro-inflammatory cytokines in the serum and the brain of mice. A synergistic reaction between aging and ZnO NP exposure occurred regarding serum interleukin 1 (IL-1) and interleukin 6 (IL-6). In the brain, increased oxidative stress level, impaired learning and memory abilities, and hippocampal pathological changes were identified, especially in old mice, following ZnO NP exposure. Then, a potential mechanism of cognitive impairment was examined. The contents of hippocampal cAMP response element binding protein (CREB), phosphorylated CREB, synapsin I, and cAMP were decreased in an age-dependent manner, and the most substantial decrease occurred in old mice treated with ZnO NPs. These findings demonstrated for the first time that aging and ZnO NP exposure synergistically influenced systemic inflammation, and indicated old individuals were more susceptible to ZnO NP-induced neurotoxicity. One of the mechanisms might due to the supression of cAMP/CREB signaling.

Effects of unregulated anthropogenic activities on mixing ratios of volatile organic air pollutants--A case study

During the months of October to November, many important festivals are celebrated in India. Celebration of these festivals are marked by extensive use of fireworks or pyrotechnics, bonfire, incense burning, open air community cooking, and temporary eateries using crude fuel such as coal, wood, kerosene, cow dung, burning of raw/semiwood, and coconut shells. The present study deals with the influence of these unregulated anthropogenic activities on ambient mixing level of volatile organic compounds (VOCs), especially some carbonyl compounds. The study was undertaken in the metropolitan city of Kolkata, India, with very high population density, which is even higher during festival period. The average total carbonyl level at different sites in Kolkata varied from 134.8 to 516.5 μg m(-3) in pre-festival season, whereas in post-festival season the same varied from 252.2 to 589.3 μg m(-3). Formaldehyde to acetaldehyde ratio altered from 0.62 in pre-festival season to 1.78 in post-festival season. Diurnal variation also altered, indicating variation in source composition of carbonyls. The total ozone forming potential calculated for all 14 carbonyls in pre-festival season increased by 35% in post-festival season. The effect of anthropogenic activities typical to the event of Diwali night characterized by intense execution of pyrotechnics resulted in significantly high level of carbonyl VOCs. Principal component analysis study for the event of Diwali shows clear contribution of the event on certain carbonyl VOCs. The results indicate elevated primary emissions of these pollutants and also their effect on formation of secondary pollutants. The study emphasizes the need of generating awareness among the communities in society as well as need for regulations to minimize the emissions and related hazards to the extent possible.

IMPLICATIONS

Altered anthropogenic activities typical of festival season including extensive use of pyrotechnics affect ambient level of volatile organic compounds, especially some carbonyls. Such activities have considerable effect on interspecies ratio and diurnal variation. They also affect formation of secondary pollutants such as tropospheric ozone. Principal component analysis (PCA) study shows clear contribution of the pyrotechnics execution on certain carbonyl VOCs. The findings emphasize the need of generating awareness in society and need for regulations to minimize the emissions.

The association between ambient air quality and cardiac rate and rhythm in ambulatory subjects

BACKGROUND

Acute increases in ambient air pollution have been associated with increased hospitalization for cardiac diseases and stroke. Triggering of cardiac arrhythmia by changes in air quality could theoretically predispose individuals to cardiac arrest or heart failure, or stroke through precipitation of atrial fibrillation. We investigated the association between air quality and cardiac rate and rhythm characteristics measured by ambulatory cardiac monitoring.

METHODS AND RESULTS

Daily ambient 3-h maximum concentrations of ozone, nitrogen dioxide and fine particulate matter, and an index summarizing these pollutants called the Air Quality Health Index (AQHI) were compared to the results of 24-h ambulatory cardiac monitoring performed for clinical purposes in 8662 patients and analyzed at the University of Ottawa Heart Institute, Canada, between 2004 and 2009. An interquartile increase in the daily 3 h- maximum AQHI was associated with a 0.9% (95% CI 0.3%, 1.5%) increase in the daily maximum heart rate and a 1.17% (95% CI 1.07%, 1.29%) increase in heart block frequency. An interquartile increase in NO2 was associated with an increase in the percentage of time in atrial fibrillation of 4.39% (-0.15, 9.15) among those ≤50 years old, and 7.1% (0.24, 14.5) among males.

CONCLUSIONS

We found evidence that air pollution may affect cardiac rate and rhythm. This may be one mechanism partially explaining the increase in strokes and cardiac events observed on days of higher air pollution.

Evaluating potential response-modifying factors for associations between ozone and health outcomes: a weight-of-evidence approach

BACKGROUND

Epidemiologic and experimental studies have reported a variety of health effects in response to ozone (O3) exposure, and some have indicated that certain populations may be at increased or decreased risk of O3-related health effects.

OBJECTIVES

We sought to identify potential response-modifying factors to determine whether specific groups of the population or life stages are at increased or decreased risk of O3-related health effects using a weight-of-evidence approach.

METHODS

Epidemiologic, experimental, and exposure science studies of potential factors that may modify the relationship between O3 and health effects were identified in U.S. Environmental Protection Agency's 2013 Integrated Science Assessment for Ozone and Related Photochemical Oxidants. Scientific evidence from studies that examined factors that may influence risk were integrated across disciplines to evaluate consistency, coherence, and biological plausibility of effects. The factors identified were then classified using a weight-of-evidence approach to conclude whether a specific factor modified the response of a population or life stage, resulting in an increased or decreased risk of O3-related health effects.

DISCUSSION

We found "adequate" evidence that populations with certain genotypes, preexisting asthma, or reduced intake of certain nutrients, as well as different life stages or outdoor workers, are at increased risk of O3-related health effects. In addition, we identified other factors (i.e., sex, socioeconomic status, and obesity) for which there was "suggestive" evidence that they may increase the risk of O3-related health effects.

CONCLUSIONS

Using a weight-of-evidence approach, we identified a diverse group of factors that should be considered when characterizing the overall risk of health effects associated with exposures to ambient O3.

[Air contamination in the Autonomous City of Buenos Aires: the current risk or future climate change, a false option]

Based on the theoretical framework of environmental risk, this article discusses the management of air quality in the Autonomous City of Buenos Aires in relation to current and potential impacts of toxic gases and global climate change on the health of the population. Information on historical and current management of the air was linked to the results of the South American Emissions, Megacities and Climate research project to assess danger, exposure, vulnerability and uncertainty as the dimensions of risk. By contextualizing public policies developed in recent decades on this subject, it was possible to identify emerging configurations of risk and uncertainties as accelerators of social vulnerability. On the one hand, the fact that there is a positive correlation between mortality, changes in temperature and air pollution was confirmed. On the other hand, it became clear that there is a disconnect between air quality management and health care management, while limitations were found in the proposed mitigation measures relating to emissions of greenhouse gases produced by fuel, revealing uncertainties regarding their efficacy.

Structured expert judgment to characterize uncertainty between PM2.5 exposure and mortality in Chile

To further the understanding and implementation of expert elicitation methods in the evaluation of public policies related to air pollution, the present study's main goal was to explore the potential strengths and weaknesses of structured expert judgment (SEJ) methodology as a way to derive a C-R function for chronic PM(2.5) exposure and premature mortality in Chile. Local experts were classified in two groups according to background and experience: physicians (Group 1) and engineers (Group 2). Experts were required to provide an estimate of the true percent change in nonaccidental mortality resulting from a permanent 1 μg/m(3) reduction in PM2.5 annual average ambient concentration across the entire Chilean territory. Cooke's Classical Model was used to combine the individual experts' assessments. Experts' mortality estimations varied markedly across groups: while experts in Group 1 delivered higher estimations than those reported in major international cohort studies, estimations from Group 2 were, to varying degrees, anchored to previous studies. Accordingly, combined distributions for each group and all experts were significantly different, due to the high sensitivity of the weighted distribution to experts' performance in calibration variables. Results of this study suggest that, while the use of SEJ has great potential for estimating C-R functions for chronic exposure to PM2.5 and premature mortality and its major sources of uncertainty in countries where no studies are available, its successful implementation is conditioned by a number of factors, which are analyzed and discussed.

Who is more affected by ozone pollution? A systematic review and meta-analysis

Ozone is associated with adverse health; however, less is known about vulnerable/sensitive populations, which we refer to as sensitive populations. We systematically reviewed epidemiologic evidence (1988-2013) regarding sensitivity to mortality or hospital admission from short-term ozone exposure. We performed meta-analysis for overall associations by age and sex; assessed publication bias; and qualitatively assessed sensitivity to socioeconomic indicators, race/ethnicity, and air conditioning. The search identified 2,091 unique papers, with 167 meeting inclusion criteria (73 on mortality and 96 on hospitalizations and emergency department visits, including 2 examining both mortality and hospitalizations). The strongest evidence for ozone sensitivity was for age. Per 10-parts per billion increase in daily 8-hour ozone concentration, mortality risk for younger persons, at 0.60% (95% confidence interval (CI): 0.40, 0.80), was statistically lower than that for older persons, at 1.27% (95% CI: 0.76, 1.78). Findings adjusted for publication bias were similar. Limited/suggestive evidence was found for higher associations among women; mortality risks were 0.39% (95% CI: -0.22, 1.00) higher than those for men. We identified strong evidence for higher associations with unemployment or lower occupational status and weak evidence of sensitivity for racial/ethnic minorities and persons with low education, in poverty, or without central air conditioning. Findings show that some populations, especially the elderly, are particularly sensitive to short-term ozone exposure.

Perception of neighborhood crime and drugs increases cardiometabolic risk in Chilean adolescents

PURPOSE

Studies report an association between neighborhood risk and both obesity and cardiometabolic risk factors (CMR) among adolescents. Here we describe the effect of perceived neighborhood risk on adiposity and CMR among Chilean adolescents.

METHODS

Participants were 523 low- to middle-income Chilean adolescents. We assessed neighborhood risk in early adolescence, adiposity in childhood and in early and later adolescence, and blood pressure and fasting glucose in later adolescence. Neighborhood risk profiles were estimated using latent profile analysis (LPA) and based on reported perceptions of crime and drug sales/use. Using linear and logistic regression, we examined the effect of neighborhood risk on adiposity and CMR.

RESULTS

Mean age in early and later adolescence was 14 and 17 years, respectively. Participants were 52% male, with a mean BMI z-score of .67, and 8% met criteria for metabolic syndrome. LPA identified two neighborhood profiles: 61% low risk and 39% high risk. In later adolescence, being in the high risk profile predicted a higher BMI z-score, waist-to-height ratio, and fat mass index (p < .05). Adolescents in the high risk profile had three times greater odds of meeting criteria for metabolic syndrome (OR = 3.1, 95% CI: 1.5, 5.8) compared with those in the low risk profile.

CONCLUSIONS

Our findings suggest that there are physiological responses to living in a neighborhood perceived as "risky," which may contribute to obesity and CMR even in adolescence. For Chilean neighborhoods with high crime and drugs, targeted public health interventions and policies for youth could be beneficial.

Synoptic weather typing applied to air pollution mortality among the elderly in 10 Canadian cities

BACKGROUND

Synoptic circulation patterns (large-scale weather systems) affect ambient levels of air pollution, as well as the relationship between air pollution and human health.

OBJECTIVE

To investigate the air pollution-mortality relationship within weather types and seasons, and to determine which combination of atmospheric conditions may pose increased health threats in the elderly age categories.

METHODS

The relative risk of mortality (RR) due to air pollution was examined using Poisson generalized linear models (GLMs) within specific weather types. Analysis was completed by weather type and age group (all ages, ≤64, 65-74, 75-84, ≥85 years) in ten Canadian cities from 1981 to 1999.

RESULTS

There was significant modification of RR by weather type and age. When examining the entire population, weather type was shown to have the greatest modifying effect on the risk of dying due to ozone (O3). This effect was highest on average for the dry tropical (DT) weather type, with the all-age RR of mortality at a population weighted mean (PWM) found to be 1.055 (95% CI 1.026-1.085). All-weather type risk estimates increased with age due to exposure to carbon monoxide (CO), nitrogen dioxide (NO2), and sulphur dioxide (SO2). On average, RR increased by 2.6, 3.8 and 1.5% for the respective pollutants between the ≤64 and ≥85 age categories. Conversely, mean ozone estimates remained relatively consistent with age. Elevated levels of air pollution were found to be detrimental to the health of elderly individuals for all weather types. However, the entire population was negatively effected by air pollution on the hot dry (DT) and hot humid (MT) days.

CONCLUSIONS

We identified a significant modification of RR for mortality due to air pollution by age, which is enhanced under specific weather types. Efforts should be targeted at minimizing pollutant exposure to the elderly and/or all age groups with respect to weather type in question.

A general and flexible methodology to define thresholds for heat health watch and warning systems, applied to the province of Québec (Canada)

Several watch and warning systems have been established in the world in recent years to prevent the effects of heat waves. However, many of these approaches can be applied only in regions with perfect conditions (e.g., enough data, stationary series or homogeneous regions). Furthermore, a number of these approaches do not account for possible trend in mortality and/or temperature series, whereas others are generally not adapted to regions with low population densities or low daily mortality levels. In addition, prediction based on multiple days preceding the event can be less accurate if it attributes the same importance to each of these days, since the forecasting accuracy actually decreases with the period. The aim of the present study was to identify appropriate indicators as well as flexible and general thresholds that can be applied to a variety of regions and conditions. From a practical point of view, the province of Québec constitutes a typical case where a number of the above-mentioned constraints are present. On the other hand, until recently, the province's watch and warning system was based on a study conducted in 2005, covering only the city of Montreal and applied to the whole province. The proposed approach is applied to each one of the other health regions of the province often experiencing low daily counts of mortality and presenting trends. The first constraint led to grouping meteorologically homogeneous regions across the province in which the number of deaths is sufficient to carry out the appropriate data analyses. In each region, mortality trends are taken into account. In addition, the proposed indicators are defined by a 3-day weighted mean of maximal and minimal temperatures. The sensitivity of the results to the inclusion of traumatic deaths is also checked. The application shows that the proposed method improved the results in terms of sensitivity, specificity and number of yearly false alarms, compared to those of the existing and other classical approaches. An additional criterion based on the Humidex is applied in a second step and a local validation is applied to historical observations at reference forecasting stations. An integrated heat health watch and warning system with thresholds that are adapted to the regional climate has thus been established for each sub-region of the province of Quebec and became operational in June 2010.

Susceptibility of older adults to health effects induced by ambient air pollutants regulated by the European Union and the United States

Air pollution is a health concern for the general population, but a few subpopulations (e.g., children, individuals with preexisting cardiovascular or respiratory diseases, etc.) are considered more susceptible to the adverse health effects attributed to air pollution. There is sufficient evidence to suggest that older adults (≥65 years old) are more susceptible to air pollution-induced health effects compared to younger adults due to decreased physiological, metabolic and compensatory processes, and a greater incidence of cardiovascular and respiratory disease. This review examines health effects induced by exposures to common ambient air pollutants regulated by the European Union and the United States. Studies were evaluated that examined the potential susceptibility of older adults to air pollutant-induced health effects. This review focuses on epidemiologic studies that directly compared the health effects of older adults to younger adults and/or the general population in order to compare populations within the same study design. Supplementary information is used from controlled human exposure studies, which examined only older adults, and animal toxicological studies, which utilized animal models of senescence, to provide coherence and biological plausibility for the health effects observed in epidemiologic studies. Overall, evidence from available published studies demonstrates that older adults may be more susceptible to air pollution-induced health effects than younger adults and/or the general population. Clinicians and other health professionals should consider advising older adults on pollution-avoiding behaviors in order to decrease the risk of adverse air pollution-related health effects.

PM2.5 mass and species trends in Santiago, Chile, 1998 to 2010: the impact of fuel-related interventions and fuel sales

Improving air quality in Santiago has been a high priority for the Chilean government. In this paper we examine trends of fine particulate matter (PM2.5) mass and species concentrations during the period 1998 to 2010 and explore the impact of fuel-related interventions and fuel sales on concentration changes. Smoothing spline functions were utilized to characterize and account for nonlinear relationships between pollutant concentrations and different parameters. Meteorology-adjusted PM2.5 concentrations were lower by 21.8 microg/m3 in 2010 compared to 1998. In this model, wind speed was the most important determinant of PM2.5 levels. A decrease in 24-hr average wind speed below 1.0 m/s was associated with a significant increase in daily PM2.5 levels, indicating a high sensitivity of PM2.5 concentrations to the accumulation of local emissions. The same regression model framework was applied to examine the trends of lead, bromine, and sulfur concentrations. Removal of lead and bromine from gasoline achieved dramatic decreases in their atmospheric concentrations. Nonetheless, both elements continue to persist, likely in the form of PbBrCl. The reduction of diesel sulfur content from 1,500 to 50 ppm corresponded to a 32% decrease in particulate sulfur levels. Lastly, a surge in PM2.5 was observed in 2005-2008. Further regression analyses suggested this was prompted by a rise in monthly petroleum-based fuel sales.

IMPLICATIONS

In this paper, we elucidate meteorology-adjusted trends of PM2.5 mass and species concentrations in Santiago and assess the efficacy of fuel-related interventions, such as the removal of lead from gasoline and reduction of sulfur content in diesel. In addition, we explore the impact of fuel sales on PM2.5 trends. Given that fuel consumption is likely to increase further in this rapidly growing city, understanding its impact on PM2.5 trends can inform future air quality control efforts in Santiago.

Elemental concentrations of ambient particles and cause specific mortality in Santiago, Chile: a time series study

BACKGROUND

The health effects of particulate air pollution are widely recognized and there is some evidence that the magnitude of these effects vary by particle component. We studied the effects of ambient fine particles (aerodynamic diameter < 2.5 μm, PM(2.5)) and their components on cause-specific mortality in Santiago, Chile, where particulate pollution is a major public health concern.

METHODS

Air pollution was collected in a residential area in the center of Santiago. Daily mortality counts were obtained from the National Institute of Statistic. The associations between PM(2.5) and cause-specific mortality were studied by time series analysis controlling for time trends, day of the week, temperature and relative humidity. We then included an interaction term between PM(2.5) and the monthly averages of the mean ratios of individual elements to PM2.5 mass.

RESULTS

We found significant effects of PM(2.5) on all the causes analyzed, with a 1.33% increase (95% CI: 0.87-1.78) in cardiovascular mortality per 10 μg/m(3) increase in the two days average of PM(2.5). We found that zinc was associated with higher cardiovascular mortality. Particles with high content of chromium, copper and sulfur showed stronger associations with respiratory and COPD mortality, while high zinc and sodium content of PM(2.5) amplified the association with cerebrovascular disease.

CONCLUSIONS

Our findings suggest that PM(2.5) with high zinc, chromium, copper, sodium, and sulfur content have stronger associations with mortality than PM(2.5) mass alone in Santiago, Chile. The sources of particles containing these elements need to be determined to better control their emissions.

The Republic of Chile: an upper middle-income country at the crossroads of economic development and aging

Chile is a developing country with a rapidly expanding economy and concomitant social and cultural changes. It is expected to become a developed country within 10 years. Chile is also characterized as being in an advanced demographic transition. Unique challenges are posed by the intersection of rapid economic development and an aging population, making Chile an intriguing case study for examining the impact of these societal-level trends on the aging experience. This paper highlights essential characteristics of this country for understanding its emerging aging society. It reveals that there is a fundamental lack of adequate and depthful epidemiologic and country-specific research from which to fully understand the aging experience and guide new policies in support of health and well-being.

Distributed lag associations between respiratory illnesses and mortality with suspended particle concentration in Tula, a highly polluted industrial region in Central Mexico

PURPOSE

We aimed to evaluate the association between changes in airborne particulate matter concentration (PM) with changes in cases of mortality, acute respiratory infections (ARI) and asthma over 2004-2008 in an industrialized and polluted region in central Mexico.

METHODS

A generalized linear model with a Poisson distribution and a negative binomial analysis was used to evaluate the influence of PM and temperature on all-cause mortality (All-cause-M), cause-specific mortality (Cause-specific-M), ARI and asthma, using cubic spline functions and distributed lags of PM. Estimated changes in relative risk were calculated for an exposure corresponding to each increase of 10 μg/m(3) in PM level.

RESULTS

Associations between PM and mortality and morbidity were statistically most consistent for total suspended particulate (TSP) than for particulate matter <10 μM aerodynamic diameter (PM10). The greatest effects in mortality were observed with a 3-week lag, and effects were greater for Cause-specific-M. We also found a displacement effect up to 4-week lag for Cause-specific-M and TSP. The greatest effects in morbidity were observed at 0-week lag, yet they were statistically marginal and were greater for asthma. We found a displacement effect at 4-5-6-week lag for asthma and TSP. All associations of mortality and morbidity, expressed as change in relative risk, were greater with PM10; however, all of them were statistically marginal.

CONCLUSIONS

Increased respiratory morbidity and mortality is associated with weekly changes of PM air pollution in the region. A reduction in air pollutants from industrial sources would benefit life quality and health of the exposed population.

A case-crossover analysis of Asian dust storms and mortality in the downwind areas using 14-year data in Taipei

This study aims to assess the association between Asian dust storms (ADS) and daily mortality in Taipei, Taiwan. A time-stratified case-crossover design was used to investigate the effects of ADS on mortality. Odds ratios (ORs) of total non-accidental (ICD-9 <800), cardiovascular (ICD-9 390-459, 785), and respiratory deaths (ICD-9 460-519, 786) were estimated for residents in Taipei metropolis over a 14-year study period between 1994 and 2007 by conditional logistic regression. Air pollution levels and temperature data were recorded by a network of 16 monitoring stations spreading around Taipei. Compared with reference days, particulate matter with aerodynamic diameter less than 10 and 2.5μm (PM(10) and PM(2.5)) increased statistically significantly by 24.2μg/m(3) and 7.9μg/m(3) per dust day, respectively. There were also statistically significant increases in sulfur dioxide (SO(2)) and ozone (O(3)) but decreases in temperature during ADS. Excess deaths were increased significantly for residents of all ages for total non-accidental deaths, with OR=1.019 (95% CI 1.003-1.035), and also for residents above 65years old, with OR=1.025 (95% CI 1.006-1.044) for total non-accidental deaths and OR=1.045 (95% CI 1.0011-1.081) for cardiovascular deaths, respectively but not for respiratory deaths during ADS. Such increases in mortality remained statistically significant in the regression models with either SO(2) or O(3). This study found that acute exposure to long-range transported Asian dust can increase the number of non-accidental and cardiovascular deaths for people of all ages and the elderly population aged above 65 on the dust storm days in Taipei, Taiwan. Further studies are still needed to find out whether mass concentrations alone or specific components in PM are responsible for excess cardiovascular deaths by ADS.

Poluição atmosférica e internações hospitalares por doenças respiratórias em crianças e adolescentes em Cubatão, São Paulo, Brasil, entre 1997 e 2004

O objetivo deste estudo foi avaliar os efeitos dos poluentes atmosféricos e suas estruturas de defasagem sobre a morbidade respiratória de crianças e adolescentes, na cidade de Cubatão, São Paulo, Brasil, entre 1997 e 2004. Um estudo ecológico de séries temporais foi realizado, analisando internações nos hospitais do Sistema Único de Saúde por doenças respiratórias de crianças e adolescentes residentes no município. Foram utilizados modelos lineares generalizados de regressão de Poisson, controlando-se para sazonalidade, temperatura, umidade e tendência de curta duração. PM10 e ozônio estiveram positiva e estatisticamente associados com as internações por doenças respiratórias. No grupo de crianças, aumentos de um interquartil nas médias móveis de sete dias do PM10 (56,5µg/m³) e de cinco dias do ozônio (46,7µg/m³) levaram a aumentos nas internações hospitalares de 9,6% (IC95%: 3,0%-16,1%) e 2,4% (IC95%: 0,1%-4,7%), respectivamente. Esforços para redução das concentrações dos poluentes do ar ainda precisam ser implementados para minimizar os seus efeitos adversos sobre crianças e adolescentes em Cubatão.

Apparent temperature and air pollution vs. elderly population mortality in Metro Vancouver

Background

Meteorological conditions and air pollution in urban environments have been associated with general population and elderly mortality, showing seasonal variation.

Objectives

This study is designed to evaluate the relationship between apparent temperature (AT) and air pollution (PM_2.5) vs. mortality in elderly population of Metro Vancouver.

Methods

Statistical analyses are performed on moving sum daily mortality rates vs. moving average AT and PM_2.5 in 1-, 2-, 3-, 5-, and 7-day models for all seasons, warm temperatures above 15°C, and cold temperatures below 10°C.

Results

Approximately 37% of the variation in all-season mortality from circulatory and respiratory causes can be explained by the variation in 7-day moving average apparent temperature (r² = 0.37, p<0.001). Although the analytical results from air pollution models show increasingly better prediction ability of longer time-intervals (r² = 0.012, p<0.001 in a 7-day model), a very weak negative association between elderly mortality and air pollution is observed.

Conclusions

Apparent temperature is associated with mortality from respiratory and circulatory causes in elderly population of Metro Vancouver. In a changing climate, one may anticipate to observe potential health impacts from the projected high- and particularly from the low-temperature extremes.

The risk of dying on days of higher air pollution among the socially disadvantaged elderly

RATIONALE

The estimated mortality rate associated with ambient air pollution based on general population studies may not be applicable to certain subgroups.

OBJECTIVE

The objective of the present study was to determine the influence of age, education, employment status and income on the risk of mortality associated with ambient air pollution.

METHODS

Daily time-series analyses tested the association between daily air pollution and daily mortality in seven Chilean urban centers during the period January 1997-December 2007. Results were adjusted for long-term trends, day-of-the week and humidex.

RESULTS

Interquartile increases in particulate matter (PM(10) and PM(2.5)), sulphur dioxide, nitrogen dioxide, carbon monoxide, and elemental and organic carbon were associated with a 4-7% increase in mortality among those who did not complete primary school (p<0.05) vs. 0.5-1.5% among university graduates (p>0.05). Among those at least 85 years of age respective estimates were 2-7%. However, among the elderly who did not complete primary school, respective estimates were 11-19% (p<0.05). The degree of effect modification was less for income and employment status than education, and sex did not modify the results.

CONCLUSION

The socially disadvantaged, especially if elderly appear to be especially susceptible to dying on days of higher air pollution. Concentrations deemed acceptable for the general population would not appear to protect this susceptible subgroup.

A review of low-level air pollution and adverse effects on human health: implications for epidemiological studies and public policy

The aim of this study was to review original scientific articles describing the relationship between atmospheric pollution and damage to human health. We also aimed to determine which of these studies mentioned public policy issues. Original articles relating to atmospheric pollution and human health published between 1995 and 2009 were retrieved from the PubMed database and analyzed. This study included only articles dealing with atmospheric pollutants resulting primarily from vehicle emissions. Three researchers were involved in the final selection of the studies, and the chosen articles were approved by at least two of the three researchers. Of the 84 non-Brazilian studies analyzed, 80 showed an association between atmospheric pollution and adverse effects on human health. Moreover, 66 showed evidence of adverse effects on human health, even at levels below the permitted emission standards. Three studies mentioned public policies aimed at changing emission standards. Similarly, the 29 selected Brazilian studies reported adverse associations with human health, and 27 showed evidence of adverse effects even at levels below the legally permitted emission standards. Of these studies, 16 mentioned public policies aimed at changing emission standards. Based on the Brazilian and non-Brazilian scientific studies that have been conducted, it can be concluded that, even under conditions that are compliant with Brazilian air quality standards, the concentration of atmospheric pollutants in Brazil can negatively affect human health. However, as little discussion of this topic has been generated, this finding demonstrates the need to incorporate epidemiological evidence into decisions regarding legal regulations and to discuss the public policy implications in epidemiological studies.

Health risk estimation due to carbon monoxide pollution at different spatial levels in Santiago, Chile

The Metropolitan Region of Santiago has been declared as nonattainment area for carbon monoxide (CO). The data was based on seven air monitoring stations that do not necessarily represent the real population exposure. Usually, a series of coefficients that relates the concentration of pollutants with health effects (betas of the concentration-response equations) are used. For the calculation of these betas, normally, a city average air pollution concentration is used; nevertheless, these betas do not necessarily represent the real risk of exposure that the inhabitants are experimented. For this reason, this study estimates two aspects that are unknown and that are necessary to policymakers in public health decisions. First, estimate the exposure at a lower spatial resolution level and, second, estimate a concentration-response curve that differs spatially and depends on the proportion of susceptible groups. We followed the Air Pollution and Health, European Approach/Spanish Multicenter Study on the Relationship Between Air Pollution and the Mortality methodology for the determination of the short-term health effect due to CO population exposure at the three spatial levels (city, zone, and county). We found that there are different risks in cardiorespiratory mortality in the group over 64 years old associated to an unequal exposure to CO in Santiago city. The higher risks are in counties located to the south-east of the city. These finding confirm the necessity to face, in a different way, the approach when evaluating control strategies and policy decision to control air pollution in Santiago.

Air pollution and hospital admissions for respiratory diseases in the subequatorial Amazon: a time series approach

The objective of the study is to evaluate the effect of the daily variation in concentrations of fine particulate matter (diameter less than 2.5µm - PM2.5) resulting from the burning of biomass on the daily number of hospitalizations of children and elderly people for respiratory diseases, in Alta Floresta and Tangará da Serra in the Brazilian Amazon in 2005. This is an ecological time series study that uses data on daily number of hospitalizations of children and the elderly for respiratory diseases, and estimated concentration of PM2.5. In Alta Floresta, the percentage increases in the relative risk (%RR) of hospitalization for respiratory diseases in children were significant for the whole year and for the dry season with 3-4 day lags. In the dry season these measurements reach 6% (95%CI: 1.4-10.8). The associations were sig-nificant for moving averages of 3-5 days. The %RR for the elderly was significant for the current day of the drought, with a 6.8% increase (95%CI: 0.5-13.5) for each additional 10µg/m3 of PM2.5. No as-sociations were verified for Tangara da Serra. The PM2.5 from the burning of biomass increased hospitalizations for respiratory diseases in children and the elderly.

Modifiers of short-term effects of ozone on mortality in eastern Massachusetts--a case-crossover analysis at individual level

BACKGROUND

Substantial epidemiological studies demonstrate associations between exposure to ambient ozone and mortality. A few studies simply examine the modification of this ozone effect by individual characteristics and socioeconomic status, but socioeconomic status was usually coded at the city level.

METHODS

This study used a case-crossover design to examine whether impacts of ozone on mortality were modified by socioeconomic status coded at the tract or characteristics at an individual level in eastern Massachusetts, US for a period May-September, 1995-2002, with a total of 157,197 non-accident deaths aging 35 years or older. We used moving averages of maximal 8-hour concentrations of ozone monitored at 8 stationary stations as personal exposure.

RESULTS

A 10 ppb increase in the four-day moving average of maximal 8-hour ozone was associated with 1.68% (95% confidence interval (CI): 0.51%, 2.87%), 1.96% (95% CI: -1.83%, 5.90%), 8.28% (95% CI: 0.66%, 16.48%), 0.44% (95% CI: -1.45%, 2.37%), -0.83% (95% CI: -2.94%, 1.32%), -1.09% (95% CI: -4.27%, 2.19%) and 6.5% (95% CI: 1.74%, 11.49%) changes in all natural deaths, respiratory disorders, diabetes, cardiovascular diseases, heart diseases, acute myocardial infarction and stroke, respectively. We did not find any evidence that the associations were significantly modified by socioeconomic status or individual characteristics although small differences of estimates across subpopulations were demonstrated.

CONCLUSIONS

Exposure to ozone was associated with specific cause mortality in Eastern Massachusetts during May-September, 1995-2002. There was no evidence that effects of ozone on mortality were significantly modified by socioeconomic status and individual characteristics.

Components of particulate air pollution and emergency department visits in Chile

The objective of the present study was to determine the association between several elements of particulates and Emergency Department (ED) visits in a general population sample. Daily time-series analyses tested the association between daily ED visit and air pollutants and components of particulates measured in Santiago Centro, a municipality, which includes downtown Santiago during the period from 2001 to 2006. The strongest individual effect was seen for elemental carbon. A 4.76 microg/m3 increase was associated with a relative risk (RR) of 1.12 (95% confidence interval [CI] = 1.10-1.14) increase in total ED visits, and a RR of 1.18 (95% CI = 1.16-1.21) for respiratory ED visit. Using factor analysis, the authors determined that traffic combustion-related particulates were significantly associated with ED visits. Among all the sources identified, traffic combustion-related particulates had the strongest association with ED visits. A factor indicating soil-sourced particles had a weaker but statistically significant observed morbidity effect. Of the many components of particulate air pollution, those from motor vehicle exhaust had the greatest observed effect on morbidity.

Who is more vulnerable to die from ozone air pollution?

BACKGROUND

Daily increases in ambient ozone have been associated with increased mortality. However, little is known about which subpopulations are more susceptible to death related to ozone.

METHODS

We conducted a case-only study in 48 US cities to identify subpopulations particularly vulnerable to ozone air pollution. Mortality and ozone data were obtained for the period 1989-2000 (May through September of each year) for 2,729,640 decedents. For each potential effect modifier, we fitted city-specific logistic regression models and pooled the results across all cities. Additionally, we examined differences in susceptibility factors according to several city characteristics using a meta-regression.

RESULTS

For each 10 ppb increase in ozone (average of lags 0 to 2), people aged > or =65 years had a 1.10% (95% confidence interval = 0.44% to 1.77%) additional increase in mortality (compared with younger ages). Other groups that were particularly susceptible were black people (additional 0.53% [0.19% to 0.87%]), women (additional 0.58% [0.18% to 0.98%]), and those with atrial fibrillation (additional 1.66% [0.03% to 3.32%]). Susceptibility factors had a larger effect in cities with lower ozone levels. For instance, the additional increase in ozone-related mortality for the elderly was 1.48% (0.81% to 2.15%) in a city with a mean ozone level of 42 ppb versus 0.45% (-0.27% to 1.19%) in a city with a level of 51 ppb.

CONCLUSIONS

We confirmed the susceptibility of the elderly to die of ambient ozone and identified other vulnerable subpopulations including women, blacks, and those with atrial fibrillation. Differences in vulnerability were particularly marked in cities with lower ozone concentrations.

Ambient ozone concentration and hospital admissions due to childhood respiratory diseases in New York State, 1991-2001

BACKGROUND AND OBJECTIVE

Respiratory diseases constitute one of the leading causes of ill health among children in New York State (NYS). The current project, a component of the NYS Environmental Public Health Tracking Program, investigated a potential association between ambient ozone (O(3)) concentration and childhood respiratory hospital admissions over 11 years in NYS.

METHODS

We used a two-stage Bayesian hierarchical model to assess the exposure-disease associations within 11 geographic regions and statewide. The data included total daily hospital admissions due to respiratory diseases for children 0-17 years old from 1991 to 2001 in NYS (N=134,099) and daily ambient O(3) level with different single-day lags. These analyses adjusted for particulate matter 10 microm in size (PM(10)), meteorological conditions, day of the week, seasonality, long-term trends, and demographic characteristics.

RESULTS

In 5 of the 11 regions, including the Upper and Lower Adirondacks, Upper Hudson Valley, Staten Island, and New York City, positive associations were found between respiratory hospital admissions and ambient O(3) level 2 days prior to the admission. Applying different statistical methods and sensitivity analysis of PM(10) did not alter these findings. When region-specific results were combined, no statewide association was apparent.

CONCLUSIONS

Geographic differences were found in the associations between O(3) levels and respiratory hospital admissions among children. In addition, we found that the two-stage model may be an appropriate approach for tracking the health effects of air pollution over time in different geographic areas when heterogeneity of risk factors across regions is present.

High temperatures enhanced acute mortality effects of ambient particle pollution in the "oven" city of Wuhan, China

BACKGROUND

We investigated whether the effect of air pollution on daily mortality is enhanced by high temperatures in Wuhan, China, using data from 2001 to 2004. Wuhan has been called an "oven" city because of its hot summers. Approximately 4.5 million permanent residents live in the 201-km(2) core area of the city.

METHOD

We used a generalized additive model to analyze pollution, mortality, and covariate data. The estimates of the interaction between high temperature and air pollution were obtained from the main effects and pollutant-temperature interaction models.

RESULTS

We observed effects of consistently and statistically significant interactions between particulate matter < or = 10 microm (PM(10)) and temperature on daily nonaccidental (p = 0.014), cardiovascular (p = 0.007), and cardiopulmonary (p = 0.014) mortality. The PM(10) effects were strongest on extremely high-temperature days (daily average temperature, 33.1 degrees C), less strong on extremely low-temperature days (2.2 degrees C), and weakest on normal-temperature days (18.0 degrees C). The estimates of the mean percentage of change in daily mortality per 10-mug/m(3) increase in PM(10) concentrations at the average of lags 0 and 1 day during hot temperature were 2.20% (95% confidence interval), 0.74-3.68) for nonaccidental, 3.28% (1.24-5.37) for cardiovascular, 2.35% (-0.03 to 4.78) for stroke, 3.31% (-0.22 to 6.97) for cardiac, 1.15% (-3.54% to 6.07) for respiratory, and 3.02% (1.03-5.04) for cardiopulmonary mortality.

CONCLUSIONS

We found synergistic effects of PM(10) and high temperatures on daily nonaccidental, cardiovascular, and cardiopulmonary mortality in Wuhan.

Age-related lung cell response to urban Buenos Aires air particle soluble fraction

Exposure to particulate matter (PM) may alter lung homeostasis inducing changes in fluid balance and host defense. Bioavailability of soluble PM compounds like polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and transition metals has been shown to play a key role in lung injury. We have previously characterized the size, shape, and chemical components of urban air particles from Buenos Aires (UAP-BA) and their biological impact on lungs. Herein, we evaluate the possible toxic effect of UAP-BA-soluble fraction (UAP-BAsf) on pulmonary cells obtained from young (1-2 months old) and aged (9-12 months old) Wistar rats using phagocytosis, oxidant-antioxidant generation, and apoptosis as endpoints. UAP-BA were collected in downtown BA and residual oil fly ash (ROFA), employed as a positive control, was collected from Boston Edison Co., Mystic Power Plant, Mystic, CT, USA. Both particle-soluble fractions (sf) were employed at concentrations ranging from 0 to 100 microg/mL. UAP-BAsf and ROFAsf even at the lowest dose assayed (10 microg/mL) showed in both lung cell populations the ability to stimulate phagocytosis and increase superoxide anion (O(2)(-)) generation. Both types of air particles caused a marked intracellular oxidant stress in aged pulmonary cells that may contribute to subsequent cell activation and production of proinflammatory mediators, leading to cell dysfunction. These data suggest that the impact of UAP-BAsf on phagocytosis, oxidant radical generation, and apoptosis is clearly dependent on the maturational state of the animal and might have different mechanisms of action.