The association between air pollution and blood pressure in traffic controllers in Santo André, São Paulo, Brazil

Ozone exposure and cardiovascular disease: A narrative review of epidemiology evidence and underlying mechanisms

Ozone (O3) poses a significant global public health concern as it exerts adverse effects on human cardiovascular health. Nevertheless, there remains a lack of comprehensive understanding regarding the relationships between O3 exposure and the risk of cardiovascular diseases (CVD), as well as the underlying biological mechanisms. To address this knowledge gap, this narrative review meticulously summarizes the existing epidemiological evidence, susceptibility, and potential underlying biological mechanisms linking O3 exposure with CVD. An increasing body of epidemiological studies has demonstrated that O3 exposure heightens the incidence and mortality of CVD, including specific subtypes such as ischemic heart disease, hypertension, and heart failure. Certain populations display heightened vulnerability to these effects, particularly children, the elderly, obese individuals, and those with pre-existing conditions. Proposed biological mechanisms suggest that O3 exposure engenders respiratory and systemic inflammation, oxidative stress, disruption of autonomic nervous and neuroendocrine systems, as well as impairment of coagulation function, glucose, and lipid metabolism. Ultimately, these processes contribute to vascular dysfunction and the development of CVD. However, some studies have reported the absence of associations between O3 and CVD, or even potentially protective effects of O3. Inconsistencies among the literature may be attributed to inaccurate assessment of personal O3 exposure levels in epidemiologic studies, as well as confounding effects stemming from co-pollutants and temperature. Consequently, our findings underscore the imperative for further research, including the development of reliable methodologies for assessing personal O3 exposure, exploration of O3 exposure's impact on cardiovascular health, and elucidation of its biological mechanisms. These endeavors will consolidate the causal relationship between O3 and cardiovascular diseases, subsequently aiding efforts to mitigate the risks associated with O3 exposure.

Early biological effects in outdoor workers exposed to urban air pollution: A systematic review

Urban outdoor workers (OWs), identified as professionals spending most of their working shifts in an urban environment, are exposed for at least 8 h/day to traffic air pollution, leading to potential health risks. This paper reports the results of a systematic review aimed at identifying the potential health outcomes of exposure to air pollutants for OWs, focusing mainly on police officers, drivers and street vendors. Health outcomes were analysed in terms of early biological effects quantified with specific measured indicators. The main inclusion criterion was the assessment of at least one early biological effect (genetic and epigenetic damage/alterations, inflammation or oxidative stress indicators, or hormonal imbalance) in a population of OWs exposed to urban air pollution. By applying the PRISMA workflow, 82 papers were included in this study. The results showed that the measured pollutant concentrations were significantly below the current occupational limit values, while exceeds the indications of WHO for urban air pollution. This exposure led to significant alterations of biological markers in OWs with respect to non-exposed subjects. In particular, OWs presented an increased frequency of micronuclei and DNA adducts as the main DNA alterations, while police officers (a category of highly exposed OWs) showed hormonal alterations affecting mainly the hypothalamic-pituitary-gonadal axis. Concerning oxidative stress and inflammation, all the analysed matrices (i.e. blood, sputum, urine and lachrymal fluids) showed increased indices for OWs respect to non-exposed groups. Therefore, the evaluation of effect biomarkers to detect early alterations provides crucial information for supporting the occupational risk management of OWs and, at broader level, allows for an insight of the early-stage health outcomes due to urban air pollution.

Global Public Health Implications of Traffic Related Air Pollution: Systematic Review

Background

Traffic-related air pollution (TRAP) has significant public health implications and a wide range of adverse health effects, including cardiovascular, respiratory, pulmonary, and other health problems. This study aimed to determine the public health impacts of traffic-related air pollution across the world that can be used as an input for protecting human health.

Methods

This study considered studies conducted across the world and full-text articles written in English. The articles were searched using a combination of Boolean logic operators (AND, OR, and NOT), MeSH, and keywords from the included electronic databases (SCOPUS, PubMed, EMBASE, Web of Science, CINAHL, and Google Scholars). The quality assessment of the articles was done using JBI tools to determine the relevance of each included article to the study.

Results

In this study, 1 282 032 participants ranging from 19 to 452 735 were included in 30 articles published from 2010 to 2022. About 4 (13.3%), 9 (30.0%), 12 (40.0%), 8 (26.7%), 2 (6.7%), 15 (50.0%), 3 (10.0%), 3 (10.0%) 1 (3.3%), and 3 (10.0%) of articles reported the association between human health and exposure to CO, PM10, PM2.5, NOx, NO, NO2, black carbon, O3, PAH, and SO2, respectively. Respiratory diseases, cancer, cognitive function problems, preterm birth, blood pressure and hypertension, diabetes, allergies and sensitization, coronary heart disease, dementia incidence, and hemorrhagic stroke were associated with exposure to TRAP.

Conclusions

Exposure to nitrogen dioxide, nitrogen oxide, sulfur dioxide, and fine particulate matter was associated with various health effects. This revealed that there is a need for the concerned organizations to respond appropriately.

Effect of air pollutants on ambulatory blood pressure

BACKGROUND AND METHODOLOGY

Air pollutants have a significant impact on public health. The aim of the study was to find out the relationship between ambulatory blood pressure measured by 24-h ambulatory blood pressure monitoring (ABPM) and the atmospheric pollutants that are measured regularly (PM10, PM2.5, NO2 and SO2). An observational study of temporal and geographic measurements of individual patients (case-time series design) was carried out in Primary Care Centres and Hypertension Units in the Barcelona metropolitan area. We included 2888 hypertensive patients≥18 years old, untreated, with a first valid ABPM performed between 2005 and 2014 and with at least one air pollution station within a radius of <3km.

RESULTS AND CONCLUSIONS

The mean age was 54.3 (SD 14.6) years. 50.1% were women and 16.9% of the sample were smokers. Mean 24-h blood pressure (BP) was 128.0 (12.7)/77.4 (9.7) mmHg. After adjusting for mean ambient temperature and different risk factors, a significant association was found between ambulatory diastolic BP (DBP) and PM10 concentrations the day before ABPM. For each increase of 10μg/m3 of PM10, an increase of 1.37mmHg 24-h DBP and 1.48mmHg daytime DBP was observed. No relationship was found between PM2.5, NO2 and SO2 and ambulatory BP, nor between any pollutant and clinical BP. The concentration of PM10 the day before the ABPM is significantly associated with an increase in 24-h DBP and daytime DBP.

Impacts of household PM2.5 pollution on blood pressure of rural residents: Implication for clean energy transition

High blood pressure associated with PM_2.5 exposure is of great concern, especially for rural residents exposed to high PM_2.5 levels. However, the impact of short-term exposure to high PM_2.5 on blood pressure (BP) has not been well elucidated. Thus, this study aims to focus on the association between short-term PM_2.5 exposure with BP of rural residents and its variation between summer and winter. Our results showed that the summertime PM_2.5 exposure concentration was 49.3 ± 20.6 μg/m³, among which, mosquito coil users had 1.5-folds higher PM_2.5 exposure than non-mosquito coil users (63.6 ± 21.7 vs 43.0 ± 16.7 μg/m³, p < 0.05). The mean systolic and diastolic BP (SBP and DBP, respectively) of rural participants were 122 ± 18.2 and 76.2 ± 11.2 mmHg in summer, respectively. The PM_2.5 exposure, SBP, and DBP in summer were 70.7 μg/m³, 9.0 mmHg, and 2.8 mmHg lower than that in winter, respectively. Furthermore, the correlation between PM_2.5 exposure and SBP was stronger in winter than that in summer, possibly due to higher PM_2.5 exposure levels in winter. The transition of household energy from solid fuels in winter to clean fuels in summer would be benefit to the decline of PM_2.5 exposure as well as BP. Results from this study suggested that the reduction of PM_2.5 exposure would have positive effect on human health.

Quantifying the dynamic characteristics of indoor air pollution using real-time sensors: Current status and future implication

People generally spend most of their time indoors, making indoor air quality be of great significance to human health. Large spatiotemporal heterogeneity of indoor air pollution can be hardly captured by conventional filter-based monitoring but real-time monitoring. Real-time monitoring is conducive to change air assessment mode from static and sparse analysis to dynamic and massive analysis, and has made remarkable strides in indoor air evaluation. In this review, the state of art, strengths, challenges, and further development of real-time sensors used in indoor air evaluation are focused on. Researches using real-time sensors for indoor air evaluation have increased rapidly since 2018, and are mainly conducted in China and the USA, with the most frequently investigated air pollutants of PM_2.5. In addition to high spatiotemporal resolution, real-time sensors for indoor air evaluation have prominent advantages in 3-dimensional monitoring, pollution peak and source identification, and short-term health effect evaluation. Huge amounts of data from real-time sensors also facilitate the modeling and prediction of indoor air pollution. However, challenges still remain in extensive deployment of real-time sensors indoors, including the selection, performance, stability, as well as calibration of sensors. In future, sensors with high performance, long-term stability, low price, and low energy consumption are welcomed. Furthermore, more target air pollutants are also expected to be detected simultaneously by real-time sensors in indoor air monitoring.

Spatio-temporal visualization and forecasting of [Formula: see text] in the Brazilian state of Minas Gerais

Air pollution due to air contamination by gases, liquids, and solid particles in suspension, is a great environmental and public health concern nowadays. An important type of air pollution is particulate matter with a diameter of 10 microns or less ([Formula: see text]) because one of the determining factors that affect human health is the size of particles in the atmosphere due to the degree of permanence and penetration they have in the respiratory system. Therefore, it is extremely interesting to monitor and understand the behavior of [Formula: see text] concentrations so that they do not exceed the established critical levels. In this work, we will study the [Formula: see text] concentrations in all available monitoring stations in the Brazilian state of Minas Gerais. To better understand its behavior, we will provide a spatio-temporal visualization of the [Formula: see text] concentrations. Besides the descriptive and visualization analysis, we consider six standard and advanced time series models that will be used to fit and forecast [Formula: see text] concentrations, with application to three locations, one in Belo Horizonte, the Minas Gerais state capital, and the monitoring stations with the lowest and highest average [Formula: see text] concentration levels.

Transportation physical activity and new-onset hypertension: A nationwide cohort study in China

The association between transportation physical activity (PA) and the risk of hypertension remains uncertain. We aimed to evaluated the prospective relation of transportation PA and new-onset hypertension among Chinese adults. A total of 9350 adults who were free of hypertension at baseline were enrolled from the China Health and Nutrition Survey (CHNS). Data on transportation PA were obtained by using self-reported questionnaires, and calculated as metabolic equivalent task (MET)-minutes/week. MET-minutes/week may account for both intensity and time spent on activities. The study outcome was new-onset hypertension, defined as systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg or diagnosed by physician or under antihypertensive treatment during the follow-up. During a median of 8.0 years (82,410 person-years) of follow-up, a total of 2949 participants developed hypertension. Overall, there was a U-shaped association between transportation PA and new-onset hypertension (P values for nonlinearity <0.001). Accordingly, compared with those with moderate transportation PA (213-<394 MET-minutes/week, the second quartile), significantly higher risks of new-onset hypertension were observed not only in participants with transportation PA < 213 MET-minutes/week (the first quartile) (HR, 1.29; 95%CI: 1.15-1.44), but in those with transportation PA ≥ 394 MET-minutes/ week (the 3-4 quartiles) (HR, 1.15; 95%CI: 1.04-1.27). Similar U-shaped correlations were found for various types of transportation PA (walking, bicycling, and motorized PA) and new-onset hypertension. In summary, moderate transportation PA is associated with a lower risk of new-onset hypertension among Chinese adults.

Does psychosocial stress modify the association of fine particulate matter and ozone with cardiovascular health indicators?

Fine particulate matter (PM_2.5) and ozone (O₃) air pollution can cause abnormal changes in blood pressure (BP), blood glucose and lipids, which are important indicators for cardiovascular health. Psychosocial stress could be a potential effect modifier for adverse health effects of air pollution, but research evidence is scarce. A cross-sectional study with 373 elderly subjects was conducted in Beijing during 2018-2019. We collected psychosocial stress information on anxiety, perceived stress and depression, obtained daily environmental data, measured resting BP, blood glucose and lipids in study participants, and analyzed the associations of PM_2.5 or O₃ with cardiovascular health indicators and the modification effect by psychosocial stress. Results showed that PM_2.5 was significantly associated with increased systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure (PP) ; and O₃ was significantly associated with elevated DBP, glycated hemoglobin (HbA1c) and total triglyceride (TG). In addition, the associations of PM_2.5 with TG, and O₃ with SBP and TG were higher in participants with high psychosocial stress, whereas the associations of O₃ with high-density lipoprotein cholesterol (HDL-C) were higher in participants with low psychosocial stress. For an interquartile range (IQR) (56.8 μg/m³) increase in PM_2.5 at 4-d moving average, TG increased by 21.43% (95% CI: 2.90, 43.29) in high perceived-stress group, and decreased by 20.05% (95% CI: -30.31, -8.28) in low perceived-stress group (p for interaction = 0.04). For an IQR (63.0 μg/m³) increase in O₃ at 2-d moving average, TG increased by 32.01% (95% CI: 7.65, 61.89) in high perceived-stress group, and increased by 7.95% (95% CI: -9.80, 29.20) only in low perceived-stress group (p for interaction = 0.04). For an IQR (64.0 μg/m³) increase in O₃ at 3-d moving average, HDL-C decreased by 4.55% (95% CI: -12.15, 3.72) in high perceived-stress group, and increased by 0.57% (95% CI: -6.99, 8.75) in low perceived-stress group (p for interaction=0.002). In conclusion, our results indicated that short-term exposures to PM_2.5 and O₃ were associated with significant changes in BP, blood glucose and lipids, and psychosocial stress may increase the susceptibility of the participants to the adverse cardiovascular effects of PM_2.5 and O₃.

Effects of domestic solid fuel combustion emissions on the biomarkers of homemakers in rural areas of the Fenwei Plain, China

BACKGROUND

The health effects of heavy solid fuel use in winter in rural China are of concern. The effects of air pollution resulting from domestic solid fuel combustion in rural households on rural homemakers' biomarkers were revealed in this study.

METHODS

In total, 75 female homemakers from rural areas of Guanzhong Basin, the Fenwei Plain, People's Republic of China, were randomly selected and divided into three groups (biomass users, coal users, and nonusers of solid fuel user [control group]). The differences in biological indicators, including 8-hydrox-2'-deoxyguanosine (8-OHdG), interlukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) in urine samples as well as blood pressure (BP, including systolic BP [SBP] and diastolic BP [DBP]) and heart rate (HR) among the groups in winter and summer were investigated using statistical analysis.

RESULTS

IL-6, 8-OHdG, HR, SBP, and DBP were significantly higher in winter than in summer (P < 0.05) owing to the poor air quality resulted from the excessive use of solid fuels in winter. Significant seasonal differences in 8-OHdG were observed for both coal and biomass users. After the influence of confounders was removed, only IL-6 levels in the urine of solid fuel users were significantly higher than that of the control group.

CONCLUSIONS

IL-6 is a sensitive biomarker representing inflammatory responses to particulate matter emitted through household solid fuel combustion. Locally, excessive use of solid fuels in winter posed serious PM_2.5 pollution in this area and adverse effects on inflammatory biomarkers in these rural homemakers and induced DNA damage related to oxidative stress.

Research on Energy Management of Hybrid Unmanned Aerial Vehicles to Improve Energy-Saving and Emission Reduction Performance

The rapid development of industry results in large energy consumption and a negative impact on the environment. Pollution of the environment caused by conventional energy sources such as petrol leads to increased demand for propulsion systems with higher efficiency and capable of energy-saving and emission reduction. The usage of hybrid technology is expected to improve energy conversion efficiency, reduce energy consumption and environmental pollution. In this paper, the simulation platform for the hybrid unmanned aerial vehicle (UAV) has been built by establishing the subsystem models of the UAV power system. Under the two chosen working conditions, the conventional cruise flight mission and the terrain tracking mission, the power tracking control and Q-Learning method have been used to design the energy management controller for the hybrid UAV. The fuel consumption and pollutant emissions under each working condition were calculated. The results show that the hybrid system can improve the efficiency of the UAV system, reduce the fuel consumption of the UAV, and so reduce the emissions of CO₂, NO_x, and other pollutants. This contributes to improving of environmental quality, energy-saving, and emission reduction, thereby contributing to the sustainable development of aviation.

Exposure to fine particles increases blood pressure of hypertensive outdoor workers: A panel study

BACKGROUND

Hypertension and air pollution are two important risk factors for cardiovascular morbidity and mortality. Although several studies suggest that air pollution has a significant impact on blood pressure, studies on long-term effects are sparse and still controversial.

OBJECTIVE

To evaluate the effects of exposure of outdoor workers to different levels of traffic-generated PM_2.5 on blood pressure.

DESIGN

This is an observational panel study.

PARTICIPANTS

88 non-smoking workers exposed to different concentrations of air pollution were evaluated weekly along four successive weeks.

MEASUREMENTS

In each week, personal monitoring of 24-h PM_2.5 concentration and 24-h ambulatory blood pressure were measured. The association between blood pressure variables and PM_2.5, adjusted for age, body mass index, time in job, daily work hours, diabetes, hypertension and cholesterol was assessed by means of multiple linear regression models fitted by least squares.

RESULTS

Exposure to PM_2.5 (ranging from 8.5 to 89.7 μg/m³) is significantly and consistently associated with an increase in average blood pressure. An elevation of 10 μg/m³ in the concentration of PM_2.5 is associated with increments of 3.9 mm Hg (CI 95% = [1.5; 6.3]) in average systolic 24-h blood pressure for hypertensive and/or diabetic workers.

CONCLUSION

Exposure to fine particles, predominantly from vehicular traffic, is associated with elevated blood pressure in hypertensive and/or diabetic workers.

Does short-term air pollution exposure have effects on blood pressure and heart rate in healthy women in the city of Niš, Serbia?

OBJECTIVE

Epidemiological research has shown that air pollution is associated with cardiovascular events, but little is known about short-term effects on blood pressure (BP) and heart rate (HR) in Serbian population. The present study assessed the short-term association between black smoke (BS) and sulphur dioxide (SO₂) levels in urban air and the daily values of blood pressure and heart rate in 98 healthy nonsmoking female volunteers.

METHODS

Generalized regression model was fitted controlling for temperature, relative humidity, air pressure, season, and the day of the week.

RESULTS

There was no association between short-term air pollution exposure and BP and HR, the exposure showed a tendency toward a decrease of diastolic BP and HR, but with no statistical significance.

CONCLUSION

The present findings did not support the conclusion that current levels of ambient BS and SO₂ may have an effect on blood pressure and heart rate in women.

Global association between ambient air pollution and blood pressure: A systematic review and meta-analysis

Although numerous studies have investigated the association of ambient air pollution with hypertension and blood pressure (BP), the results were inconsistent. We performed a comprehensive systematic review and meta-analysis of these studies. Seven international and Chinese databases were searched for studies examining the associations of particulate (diameter<2.5 μm (PM_2.5), 2.5-10 μm (PM_2.5-10) or >10 μm (PM₁₀)) and gaseous (sulfur dioxide (SO₂), nitrogen dioxide (NO₂), nitrogen oxides (NO_x), ozone (O₃), carbon monoxide (CO)) air pollutants with hypertension or BP. Odds ratios (OR), regression coefficients (β) and their 95% confidence intervals were calculated to evaluate the strength of the associations. Subgroup analysis, sensitivity analysis, and meta-regression analysis were also conducted. The overall meta-analysis showed significant associations of long-term exposures to PM_2.5 with hypertension (OR = 1.05), and of PM₁₀, PM_2.5, and NO₂ with DBP (β values: 0.47-0.86 mmHg). In addition, short-term exposures to four (PM₁₀, PM_2.5, SO₂, NO₂), two (PM_2.5 and SO₂), and four air pollutants (PM₁₀, PM_2.5, SO₂, and NO₂), were significantly associated with hypertension (ORs: 1.05-1.10), SBP (β values: 0.53-0.75 mmHg) and DBP (β values: 0.15-0.64 mmHg), respectively. Stratified analyses showed a generally stronger relationship among studies of men, Asians, North Americans, and areas with higher air pollutant levels. In conclusion, our study indicates a positive association between ambient air pollution and increased BP and hypertension. Geographical and socio-demographic factors may modify the pro-hypertensive effects of air pollutants.

Air pollution and hospitalizations in the largest Brazilian metropolis

OBJECTIVE

To evaluate the impact of air pollution on hospitalizations for respiratory and cardiovascular diseases in the largest Brazilian metropolis.

METHODS

This study was carried out at the Metropolitan Region of São Paulo, Brazil. Environmental data were obtained from the network of monitoring stations of nine municipalities. Air pollution exposure was measured by daily means of PM₁₀ (particles with a nominal mean aerodynamic diameter ≤ 10 μm) per municipality, while daily counts of hospitalizations for respiratory and cardiovascular diseases within the Brazilian Unified Health System were the outcome. For each municipality a time series analysis was carried out in which a semiparametric Poisson regression model was the framework to explain the daily fluctuations on counts of hospitalizations over time. The results were combined in a meta-analysis to estimate the overall risk of PM₁₀ in hospitalizations for respiratory and cardiovascular diseases at the Metropolitan Region of São Paulo.

RESULTS

Regarding hospitalizations for respiratory diseases, the effect estimates were statistically significant (p < 0.05) for all municipalities, except Santo André and Taboão da Serra. The RR (Relative Risk) of this outcome for an increase of 10 µg/m³ in the levels of PM₁₀ ranged from 1.011 (95%CI 1.009–1.013) for São Paulo to 1.032 (95%CI 1.024–1.040) in São Bernardo do Campo. The RR of hospitalization for respiratory diseases in children for an increase of 10 µg/m3 of PM₁₀ ranged from 1.009 (95%CI 1.001–1.017) in Santo André to 1.077 (95%CI 1.056–1.098) in Mauá. Only São Paulo and São Bernardo do Campo presented positive and statistically significant results for hospitalizations for cardiovascular diseases.

CONCLUSIONS

This is the first study to estimate the risk of illness from air pollution in the set of municipalities of the Metropolitan Region of São Paulo, Brazil. Global estimates of the effect of exposure to pollution in the region indicated associations only with respiratory diseases. Only São Paulo and São Bernardo do Campo showed an association between the levels of PM₁₀ and hospitalizations for cardiovascular diseases.

Effects of air pollution caused by sugarcane burning in Western São Paulo on the cardiovascular system

OBJECTIVE

To evaluate the effects of acute exposure to air pollutants (NO₂ and PM₁₀) on hospitalization of adults and older people with cardiovascular diseases in Western São Paulo.

METHODS

Daily cardiovascular-related hospitalization data (CID10 – I00 to I99) were acquired by the Department of Informatics of the Brazilian Unified Health System (DATASUS) from January 2009 to December 2012. Daily levels of NO₂ and PM₁₀ and weather data were obtained from Companhia Ambiental do Estado de São Paulo (CETESB – São Paulo State Environmental Agency). To estimate the effects of air pollutants exposure on hospital admissions, generalized linear Poisson regression models were used.

RESULTS

During the study period, 6,363 hospitalizations were analysed. On the day of NO₂ exposure, an increase of 1.12% (95%CI 0.05–2.20) was observed in the interquartile range along with an increase in hospital admissions. For PM₁₀, a pattern of similar effect was observed; however, results were not statistically significant.

CONCLUSIONS

Even though with values within established limits, NO₂ is an important short-term risk factor for cardiovascular morbidity.

Advancing the framework for considering the effects of climate change on worker safety and health

In 2009, a preliminary framework for how climate change could affect worker safety and health was described. That framework was based on a literature search from 1988-2008 that supported seven categories of climate-related occupational hazards: (1) increased ambient temperature; (2) air pollution; (3) ultraviolet radiation exposure; (4) extreme weather; (5) vector-borne diseases and expanded habitats; (6) industrial transitions and emerging industries; and (7) changes in the built environment. This article reviews the published literature from 2008-2014 in each of the seven categories. Additionally, three new topics related to occupational safety and health are considered: mental health effects, economic burden, and potential worker safety and health impacts associated with the nascent field of climate intervention (geoengineering). Beyond updating the literature, this article also identifies key priorities for action to better characterize and understand how occupational safety and health may be associated with climate change events and ensure that worker health and safety issues are anticipated, recognized, evaluated, and mitigated. These key priorities include research, surveillance, risk assessment, risk management, and policy development. Strong evidence indicates that climate change will continue to present occupational safety and health hazards, and this framework may be a useful tool for preventing adverse effects to workers.

Association of long-term exposure to local industry- and traffic-specific particulate matter with arterial blood pressure and incident hypertension

BACKGROUND

Long-term exposure to fine particulate matter (PM2.5) may lead to increased blood pressure (BP). The role of industry- and traffic-specific PM2.5 remains unclear.

OBJECTIVE

We investigated the associations of residential long-term source-specific PM2.5 exposure with arterial BP and incident hypertension in the population-based Heinz Nixdorf Recall cohort study.

METHODS

We defined hypertension as systolic BP≥140mmHg, or diastolic BP≥90mmHg, or current use of BP lowering medication. Long-term concentrations of PM2.5 from all local sources (PM2.5ALL), local industry (PM2.5IND) and traffic (PM2.5TRA) were modeled with a dispersion and chemistry transport model (EURAD-CTM) with a 1km(2) resolution. We performed a cross-sectional analysis with BP and prevalent hypertension at baseline, using linear and logistic regression, respectively, and a longitudinal analysis with incident hypertension at 5-year follow-up, using Poisson regression with robust variance estimation. We adjusted for age, sex, body mass index, lifestyle, education, and major road proximity. Change in BP (mmHg), odds ratio (OR) and relative risk (RR) for hypertension were calculated per 1μg/m(3) of exposure concentration.

RESULTS

PM2.5ALL was highly correlated with PM2.5IND (Spearman's ρ=0.92) and moderately with PM2.5TRA (ρ=0.42). In adjusted cross-sectional analysis with 4539 participants, we found positive associations of PM2.5ALL with systolic (0.42 [95%-CI: 0.03, 0.80]) and diastolic (0.25 [0.04, 0.46]) BP. Higher, but less precise estimates were found for PM2.5IND (systolic: 0.55 [-0.05, 1.14]; diastolic: 0.35 [0.03, 0.67]) and PM2.5TRA (systolic: 0.88 [-1.55, 3.31]; diastolic: 0.41 [-0.91, 1.73]). We found crude positive association of PM2.5TRA with prevalence (OR 1.41 [1.10, 1.80]) and incidence of hypertension (RR 1.38 [1.03, 1.85]), attenuating after adjustment (OR 1.19 [0.90, 1.58] and RR 1.28 [0.94, 1.72]). We found no association of PM2.5ALL and PM2.5IND with hypertension.

CONCLUSIONS

Long-term exposures to all-source and industry-specific PM2.5 were positively related to BP. We could not separate the effects of industry-specific PM2.5 from all-source PM2.5. Estimates with traffic-specific PM2.5 were generally higher but inconclusive.

Health status of male steel workers at an electric arc furnace (EAF) in Trentino, Italy

Background

The aim of this retrospective cohort study was to determine if the workers of an Electric Arc Furnace (EAF), which recycles scrap, had higher mortality and morbidity due to possible exposure to pollutants at work. EAFs do not run on coke ovens. In EAFs 40 % of the particulate matter (PM) is made up of PM _2.5. The foundry dust contained iron, aluminum, zinc, manganese, lead, chromium, nickel, cadmium, mercury, arsenic, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls and dioxins.

Methods

Mortality study: a cohort of 331 exposed workers (6731 person-years) was studied from 19/03/1979 to 31/12/2009 (mean follow up 20.7 years). The group of exposed workers was compared to the general population and to a small control group of 32 workers from the same company.

Morbidity study: rates of exemption from health fee for the seven major diseases of 235 exposed workers were compared to the rates of exemption in the Province of Trento.

Results

Mortality study: an excess mortality was found in the exposed workers as compared to the general population (SMR 1.13; 95 % CI: 0.76–1.62; 29 deaths) and to the internal group (RR 2.34; 95 % CI: 0.39–95.7). The mortality rate was increased for all tumours (SMR 1.36; 95 % CI: 0.75–2.29; 14 cases), for lung cancer (SMR 3.35; 95 % CI 1.45–6.60; 8 cases), for ischemic heart disease (SMR 1.27; 95 % CI: 0.35–3.26; 4 cases), for chronic liver disease (SMR 1.16; 95 % CI: 0.14–4.20; 2 cases) and for injury and poisoning (SMR 1.32; 95 % CI: 0.48–2.88; 6 cases).

Morbidity study: there was a statistically significant increase of diabetes, rheumatoid arthritis, hypertension and cardiovascular diseases in exposed workers.

Conclusions

With the limitations of this relatively small cohort, we found a statistically significant increase of diabetes, cardiovascular diseases and deaths due to lung cancer in exposed workers. These findings cannot be explained by PAH exposure alone; metal particulates are the most important pollutants in the working area of EAFs. A reliable method for measuring metal PM in tissues is urgently needed for exposure assessment. This study underlines the necessity to maximize the standards of security toward foundry dusts/diffuse emission. Further studies on EAF’s are needed to confirm our findings and to increase statistical power.

Noninvasive effects measurements for air pollution human studies: methods, analysis, and implications

Human exposure studies, compared with cell and animal models, are heavily relied upon to study the associations between health effects in humans and air pollutant inhalation. Human studies vary in exposure methodology, with some work conducted in controlled settings, whereas other studies are conducted in ambient environments. Human studies can also vary in the health metrics explored, as there exists a myriad of health effect end points commonly measured. In this review, we compiled mini reviews of the most commonly used noninvasive health effect end points that are suitable for panel studies of air pollution, broken into cardiovascular end points, respiratory end points, and biomarkers of effect from biological specimens. Pertinent information regarding each health end point and the suggested methods for mobile collection in the field are assessed. In addition, the clinical implications for each health end point are summarized, along with the factors identified that can modify each measurement. Finally, the important research findings regarding each health end point and air pollutant exposures were reviewed. It appeared that most of the adverse health effects end points explored were found to positively correlate with pollutant levels, although differences in study design, pollutants measured, and study population were found to influence the magnitude of these effects. Thus, this review is intended to act as a guide for researchers interested in conducting human exposure studies of air pollutants while in the field, although there can be a wider application for using these end points in many epidemiological study designs.

Weight-of-evidence evaluation of short-term ozone exposure and cardiovascular effects

There is a relatively large body of research on the potential cardiovascular (CV) effects associated with short-term ozone exposure (defined by EPA as less than 30 days in duration). We conducted a weight-of-evidence (WoE) analysis to assess whether it supports a causal relationship using a novel WoE framework adapted from the US EPA's National Ambient Air Quality Standards causality framework. Specifically, we synthesized and critically evaluated the relevant epidemiology, controlled human exposure, and experimental animal data and made a causal determination using the same categories proposed by the Institute of Medicine report Improving the Presumptive Disability Decision-making Process for Veterans ( IOM 2008). We found that the totality of the data indicates that the results for CV effects are largely null across human and experimental animal studies. The few statistically significant associations reported in epidemiology studies of CV morbidity and mortality are very small in magnitude and likely attributable to confounding, bias, or chance. In experimental animal studies, the reported statistically significant effects at high exposures are not observed at lower exposures and thus not likely relevant to current ambient ozone exposures in humans. The available data also do not support a biologically plausible mechanism for CV effects of ozone. Overall, the current WoE provides no convincing case for a causal relationship between short-term exposure to ambient ozone and adverse effects on the CV system in humans, but the limitations of the available studies preclude definitive conclusions regarding a lack of causation. Thus, we categorize the strength of evidence for a causal relationship between short-term exposure to ozone and CV effects as "below equipoise."

Enriched inorganic compounds in diesel exhaust particles induce mitogen-activated protein kinase activation, cytoskeleton instability, and cytotoxicity in human bronchial epithelial cells

This study assessed the effects of the diesel exhaust particles on ERK and JNK MAPKs activation, cell rheology (viscoelasticity), and cytotoxicity in bronchial epithelial airway cells (BEAS-2B). Crude DEP and DEP after extraction with hexane (DEP/HEX) were utilized. The partial reduction of some DEP/HEX organics increased the biodisponibility of many metallic elements. JNK and ERK were activated simultaneously by crude DEP with no alterations in viscoelasticity of the cells. Mitochondrial activity, however, revealed a decrease through the MTT assay. DEP/HEX treatment increased viscoelasticity and cytotoxicity (membrane damage), and also activated JNK. Our data suggest that the greater bioavailability of metals could be involved in JNK activation and, consequently, in the reduction of fiber coherence and increase in the viscoelasticity and cytotoxicity of BEAS cells. The adverse findings detected after exposure to crude DEP and to DEP/HEX reflect the toxic potential of diesel compounds. Considering the fact that the cells of the respiratory epithelium are the first line of defense between the body and the environment, our data contribute to a better understanding of the pathways leading to respiratory cell injury and provide evidence for the onset of or worsening of respiratory diseases caused by inorganic compounds present in DEP.

Particle pollution in Rio de Janeiro, Brazil: increase and decrease of pro-inflammatory cytokines IL-6 and IL-8 in human lung cells

Particle pollution from urban and industrialized regions in Rio de Janeiro (RJ), Brazil was analyzed for toxic and pro-inflammatory (cytokines: IL-6, IL-8, IL-10) responses in human bronchial epithelial cells. Trace elements contribution was studied. Airborne particulate matter was collected at: three industrial sites Ind-1 (PM10) and Ind-2a and 2b (PM2.5); Centro urban area (PM10) and two rural sites (PM2.5, PM10). PM10 acetone extracts were toxic and did not elicit cytokine release; aqueous extracts were less toxic and stimulated the release of IL-6 and IL-8. PM2.5 aqueous extracts from Ind-2 decreased the release of IL-6 and IL-8. Zinc concentration was higher at the industrial and rural reference sites (Ref-1-2) although metals were not associated to cytokines changes. These results demonstrate that PM from RJ can either increase or decrease cytokine secretion in vitro while being site specific and time dependent.

Circulatory disease mortality rates in the elderly and exposure to PM(2.5) generated by biomass burning in the Brazilian Amazon in 2005

The aim of this study was to analyze the association between the exposure to fine particulate matter and circulatory disease mortality rates in the elderly living in the Brazilian Amazon. An ecological study of circulatory disease, acute myocardial infarction and cerebrovascular disease mortality rates in micro areas of the Brazilian Amazon was carried out. The environmental exposure indicator used was percentage hours of PM(2.5) concentrations > 25µg/m(3) divided by the total number of estimated hours of PM(2.5) in 2005. The association between exposure and circulatory disease mortality rates was strongest in the oldest age group. No significant statistical association was found between cerebrovascular disease mortality rates and exposure. Circulatory disease mortality rates in the elderly living in the Amazon have been influenced by atmospheric pollution from emissions caused by forest fires.

Ozone is associated with an increased risk of respiratory exacerbations in patients with cystic fibrosis

Background

Tropospheric oxidant pollutants may injure the respiratory tract. Cystic fibrosis (CF) respiratory disease involves significant inflammation and excessive oxidative stress, and exposure to air pollutants can magnify the lung damage. The objective of this study was to investigate the association between the short-term variation in the concentration of air pollutants in metropolitan São Paulo, Brazil, and the occurrence of respiratory exacerbations in children and adolescents with CF.

Methods

A longitudinal panel of repeated measurements was obtained from 103 patients attending the outpatient center of our institution from September 6, 2006 through September 4, 2007. Daily concentrations of inhaled particulate matter, sulfur dioxide, nitrogen dioxide, ozone (O₃), carbon monoxide, and meteorologic variables, such as the minimum temperature and relative humidity, were evaluated. The generalized estimation equation model for binomial distribution was used to assess the impact of these measurements on the occurrence of acute respiratory exacerbations.

Results

In total, 103 patients with CF (median age, 8.9 years) made 408 visits, with a mean ± SD of 4 ± 1.74 visits per patient (range, 2-9). A respiratory disease exacerbation was diagnosed on 142 visits (38.4%). An interquartile range increase in the O₃ concentration (45.62 μg/m³) had a positive, delayed (2 days after exposure) effect on the risk of a respiratory exacerbation (relative risk = 1.86; 95% CI, 1.14-3.02).

Conclusions

This study demonstrates that exposure to short-term air pollution in a large urban center increases the risk of a pulmonary exacerbation in patients with CF.

First trimester exposure to ambient air pollution, pregnancy complications and adverse birth outcomes in Allegheny County, PA

Despite numerous studies of air pollution and adverse birth outcomes, few studies have investigated preeclampsia and gestational hypertension, two pregnancy disorders with serious consequences for both mother and infant. Relying on hospital birth records, we conducted a cohort study identifying 34,705 singleton births delivered at Magee-Women's Hospital in Pittsburgh, PA between 1997 and 2002. Particle (<10 μm-PM10; <2.5 μm-PM2.5) and ozone (O3) exposure concentrations in the first trimester of pregnancy were estimated using the space-time ordinary Kriging interpolation method. We employed multiple logistic regression estimate associations between first trimester exposures and preeclampsia, gestational hypertension, preterm delivery, and small for gestational age (SGA) infants. PM2.5 and O3 exposures were associated with preeclampsia (adjusted OR = 1.15, 95% CI = 0.96-1.39 per 4.0 μg/m(3) increase in PM2.5; adjusted OR = 1.12, 95% CI = 0.89-1.42 per 16.8 ppb increase in O3), gestational hypertension (for PM2.5 OR = 1.11, 95 % CI = 1.00-1.23; for O3 OR = 1.12, 95 % CI = 0.97-1.29), and preterm delivery (for PM2.5 ORs = 1.10, 95% CI = 1.01-1.20; for O3 ORs = 1.23, 95% CI = 1.01-1.50). Smaller 5-8 % increases in risk were also observed for PM10 with gestational hypertension and SGA, but not preeclampsia. Our data suggest that first trimester exposure to particles, mostly PM2.5, and ozone, may increase the risk of developing preeclampsia and gestational hypertension, as well as preterm delivery and SGA.

Association between particulate matter air pollution and monthly inhalation and nebulization procedures in Ribeirão Preto, São Paulo State, Brazil

The study was designed to investigate the impact of air pollution on monthly inhalation/nebulization procedures in Ribeirão Preto, São Paulo State, Brazil, from 2004 to 2010. To assess the relationship between the procedures and particulate matter (PM10) a Bayesian Poisson regression model was used, including a random factor that captured extra-Poisson variability between counts. Particulate matter was associated with the monthly number of inhalation/nebulization procedures, but the inclusion of covariates (temperature, precipitation, and season of the year) suggests a possible confounding effect. Although other studies have linked particulate matter to an increasing number of visits due to respiratory morbidity, the results of this study suggest that such associations should be interpreted with caution.

Association between fine particulate matter and the peak expiratory flow of schoolchildren in the Brazilian subequatorial Amazon: a panel study

BACKGROUND

Exposure to high levels of particulate matter with an aerodynamic diameter less than 2.5 μm (PM(2.5)) resulting from biomass burning is frequent in the subequatorial Amazon region.

OBJECTIVE

To investigate whether or not current exposure to PM(2.5) in the Brazilian Amazon has adverse effects on the daily peak expiratory flow (PEF) of schoolchildren.

METHODS

The study design consisted of a panel comprising 309 children aged 6 to 15 years from the same school. PEF was measured daily, except weekends and holidays, from August to December 2006. Each child contributed to the study up to 67 daily measurements. All together there were 19115 PEF measures. Participation rate was 90%. Daily measurements of PM(2.5), temperature, and humidity as well as passive smoking, and subject features were regarded in the statistical analysis. Various exposures of PM(2.5) were considered throughout the analysis, among them 24-hour, 12-hour, 6-hour, and 5-hour means. To account for subject responses to confounders, mixed effects models were applied. The effects were evaluated considering air pollution levels on the current day or at 1- or 2-day lags and the averages of 0-1-day lags, 1-2-day lags and 0-, 1-, and 2-day lags.

RESULTS

The 24-hour PM(2.5) means ranged from 6.39 to 99.91 μg/m(3). The adjusted models for the entire group of children revealed adverse effects. For instance, for an increase of 10 μg/m(3) in PM(2.5,) the reduction in the PEF average varied between 0.26 l/min (95% Confidence Interval (CI): -0.49; -0.04) and 0.38 l/min (95% CI: -0.71; -0.04). Restricted to the subgroup of non-asthmatic children, classified as such according to the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire, there was a reduction in the PEF ranging from 0.38 l/min (95% CI: -0.63; -0.13) to 0.53 l/min (95% CI: -0.90; -0.16) for an increase of 10 μg/m(3) in PM(2.5). There was no significant effect in the asthmatic group. When stratified by time of the day children were at school, the concurrent effects of air pollution on PEF were not significant, whereas the 6-hour exposure from 0 am to 5:30 am was significant for both morning and afternoon groups. Finally, the 24-hour mean lagged effect was only significant for the afternoon group of children. For an increase of 10 μg/m(3) in PM(2.5,) there was a reduction in the PEF that ranged from 0.41 l/min (95% CI: -0.76; -0.06) to 0.49 l/min (95% CI: -0.91; -0.07).

CONCLUSION

Exposure to current levels of PM(2.5) in the Brazilian Amazon was associated with reductions in the lung function of schoolchildren. The adverse effects were more consistent in non-asthmatic children and with respect to the 6-hour mean from 0 am to 5.30 am.

Ambient air pollution exposure and blood pressure changes during pregnancy

BACKGROUND

Maternal exposure to ambient air pollution has been associated with adverse birth outcomes such as preterm delivery. However, only one study to date has linked air pollution to blood pressure changes during pregnancy, a period of dramatic cardiovascular function changes.

OBJECTIVES

We examined whether maternal exposures to criteria air pollutants, including particles of less than 10 μm (PM(10)) or 2.5 μm diameter (PM(2.5)), carbon monoxide (CO), nitrogen dioxide (NO(2)), sulfur dioxide (SO(2)), and ozone (O(3)), in each trimester of pregnancy are associated with magnitude of rise of blood pressure between the first 20 weeks of gestation and late pregnancy in a prospectively followed cohort of 1684 pregnant women in Allegheny County, PA.

METHODS

Air pollution measures for maternal ZIP code areas were derived using Kriging interpolation. Using logistic regression analysis, we evaluated the associations between air pollution exposures and blood pressure changes between the first 20 weeks of gestation and late pregnancy.

RESULTS

First trimester PM(10) and ozone exposures were associated with blood pressure changes between the first 20 weeks of gestation and late pregnancy, most strongly in non-smokers. Per interquartile increases in first trimester PM(10) and O(3) concentrations were associated with mean increases in systolic blood pressure of 1.88 mm Hg (95% CI=0.84 to 2.93) and 1.84 (95% CI=1.05 to 4.63), respectively, and in diastolic blood pressure of 0.63 mm Hg (95% CI=-0.50 to 1.76) and 1.13 (95% CI=-0.46 to 2.71) in non-smokers.

CONCLUSIONS

Our novel finding suggests that first trimester PM(10) and O(3) air pollution exposures increase blood pressure in the later stages of pregnancy. These changes may play a role in mediating the relationships between air pollution and adverse birth outcomes.

Vascular and thrombogenic effects of pulmonary exposure to Libby amphibole

Exposure to Libby amphibole (LA) asbestos is associated with increased incidences of human autoimmune disease and mortality related to cardiovascular diseases. However, the systemic and vascular impacts are less well examined because of the dominance of pulmonary disease. It was postulated that regardless of the type of exposure scenario, LA exposure might produce systemic and vascular inflammogenic and thrombotic alterations in healthy and cardiovascular compromised rat models. Samples from three independent studies were examined. In the first study, male Wistar Kyoto (WKY), spontaneously hypertensive (SH), and SH heart failure (SHHF) rats were intratracheally instilled once with 0 (vehicle), 0.25, or 1 mg/rat of LA. In the second study, F344 rats were instilled with vehicle or LA at 0.5, 1.5, or 5 mg/rat. In the third study, F344 rats were instilled with the same mass concentrations of LA delivered by biweekly multiple instillations over 3 mo to simulate an episodic subchronic exposure. Complete blood count, platelet aggregation, serum cytokines, and biomarkers of systemic and aortic effects were examined. LA reduced adenosine diphosphate (ADP)-induced platelet aggregation and decreased circulating platelets in WKY (1 mg/rat) and F344 (5 mg/rat) at the 3-mo time point but did not do so in SH or SHHF rats. A decline in circulating lymphocytes with age appeared to be exacerbated by LA exposure in F344 rats but the differences were not significant. Aorta mRNA expression for biomarkers of oxidative stress (HO-1, LOX-1), inflammation (MIP-2), and thrombosis (tPA, PAI-1, vWf) were increased at baseline in SH and SHHF relative to WKY. LA exposure upregulated several of these biomarkers and also those involved in aortic contractility of WKY rats at 3 mo, suggesting thrombogenic, vasocontractile, and oxidative stress-mediated impairments. The aorta changes in F344 rats were less remarkable than changes noted in WKY following LA exposure. In conclusion, exposure to LA decreased circulating platelets and platelet coagulability while increasing the expression of oxidative stress, thrombosis, and vasoconstriction biomarkers in the aorta of healthy rats. These changes were similar to those noted at baseline in SH and SHHF rats, suggesting that LA-induced pulmonary injury might increase the risk of developing cardiovascular disease in healthy individuals.