Association between ambient fine particulate matter with blood pressure levels among Iranian individuals admitted for cardiac and respiratory diseases: Data from CAPACITY study.

BACKGROUND: The relation between air pollution and cardiovascular diseases (CVDs) risk factors, especially blood pressure (BP) levels, has been less frequently assessed. The aim of this study was evaluating the association between air pollutants of less than 2.5 µm [particulate matter (PM2.5)] and BP indices among individuals admitted with CVDs and pulmonary diseases. METHODS: This cross-sectional study was in context of air pollution associated with hospitalization and mortality of CVDs and respiratory diseases (CAPACITY) study. Data of 792 Iranian patients referring to two hospitals in Isfahan, Iran, for cardiovascular or respiratory problems from March 2011 to March 2012 were used for analysis. BP indices including systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure (MAP) were obtained from patients' medical forms and mean PM2.5 concentrations during 24 hours prior to admission of each patient were obtained from Isfahan Department of Environment (DOE). RESULTS: Mean ± standard deviation (SD) of participants' age were 62.5 ± 15.9 years. All BP indices on admission were significantly higher in women compared with men. Adjustment of all potential confounders including age, sex, temperature, wind speed, and dew point revealed that increasing one quartile in PM2.5 concentrations had been associated with 1.98 mmHg raising in SBP at the time of admission [95% confidence interval (CI) = 0.41-3.54, P = 0.010]. Women with cardiac diseases had higher all BP indices with increased PM2.5 concentration [SBP: ß: 4.30, 95% CI = 0.90-7.70, P = 0.010; DBP: ß: 1.89, 95% CI = 0.09-3.69, P = 0.040; MAP: ß: 3.09, 95% CI = 0.68-5.51, P= 0.010, respectively). CONCLUSION: Our findings suggest that increasing PM2.5 concentration has been positively associated with raising SBP in total population and all BP indices among women with cardiac problems at admission time. Several comprehensive studies are required for confirming these relations.

Correlation between air pollution and hospitalization due to myocardial infarction.

BACKGROUND: Air pollution is associated with increased risk of cardiovascular disease (CVD). This study aims to evaluate the correlation between air pollutants and hospitalization due to myocardial infarction (MI) as part of "correlation of air pollution with hospitalization and mortality of CVDs and respiratory diseases (CAPACITY) study". METHODS: This case-crossover study analyzed the data of 319 patients who were admitted with diagnosis of ST-elevation MI (STEMI) or non-ST-elevation MI (NSTEMI) in three main hospitals of Isfahan, Iran. The data of airborne pollutants including particulate matter < 10 µm (PM10), particulate matter < 2.5 µm (PM2.5), nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO), and ozone (O3) as well as climatic indices (temperature, wind speed, and humidity) at 24 hours, 48 hours, and one week before admission were extracted from CAPACITY study. The conditional logistic regression method was used to evaluate the correlation between air pollutants and MI hospitalization. RESULTS: 319 patients with mean age of 63.15 ± 28.14 years, including 238 men (74.6%), and 207 patients with STEMI (64.8%) were recruited. The risk of hospitalization significantly increased in patients with STEMI and 10-unit increment in PM2.5 at 48 hours before admission [odds ratio (OR) = 3.70, 95% confidence interval (CI): 1.69-7.69]. Although, majority of air pollutants had positive association with hospitalization in patients with NSTEMI, they were not statistically significant. CONCLUSION: This study showed significant association between elevated PM2.5 at 48 hours before admission and hospitalization of patients with STEMI. This finding can warn policymakers to design better care services for patients at risk of acute MI during the times of increased air pollution.

Association between ambient air pollution and hospitalization caused by atrial fibrillation.

BACKGROUND: Many studies have shown the worst effects of air pollution on cardiovascular diseases (CVDs). Present study focused on the relationship between atrial fibrillation (AF), as one of the common arrhythmias, and air pollutants in Isfahan, Iran, an industrial city in the Middle East. METHODS: A case-crossover design was used to explore the associations between air pollution and AF hospitalized patients with ventricular response (VR) > 90 beats per minute (bpm) (fast response) and those with VR ≤ 90 bpm. All patients' records were extracted from their hospital files. Air pollutants data including particulate matter less than 10 µ (PM10), PM2.5, carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3) were obtained from the Correlation of Air Pollution with Hospitalization and Mortality of Cardiovascular and Respiratory Diseases (CAPACITY) study. Conditional logistic regression test was used to measure the relationship between pollutants and hospitalization due to AF. RESULTS: Records of 369 patients, including 173 men (46.9%) who were hospitalized for AF during the study period and had complete data were extracted. Although a positive but not statistically significant relationship was shown between 10-unit increases in all pollutants (except PM10) and the hospitalization due to AF in patients with rapid VR (RVR), the only significant relationship was observed in case of NO2 [odds ratio (OR) = 1.26, 95% confidence interval (CI) = 1.0-2.1, P = 0.031]. CONCLUSION: This study showed positive significant relationships between NO2 and the hospitalization due to AF in patients with RVR. NO2 is a greenhouse gas whose levels are expected to increase due to global environmental changes. Therefore, relevant strategies should be adopted to decrease its levels, especially in industrial cities like Isfahan.

Polycyclic aromatic hydrocarbons (PAHs) in water and sediment of Hoor Al-Azim wetland, Iran: a focus on source apportionment, environmental risk assessment, and sediment-water partitioning.

The concentration, source, and ecological risk of 16 polycyclic aromatic hydrocarbons (PAHs) in water and sediment samples in Hoor Al-Azim wetland, a significant freshwater wetland in Lower Mesopotamia, were evaluated. Total PAHs concentrations varied from 15.3 to 160.15 ng/L, and 15.78 to 410.2 µg/Kg in water and sediment, respectively. PAHs pollution levels in sediments compared with sediment quality guidelines (SQG) were found to be moderate in two stations and low in water and the rest of sediment stations. Based on the diagnostic ratio analysis, cluster analysis (CA), and principal component analysis-multiple linear regression (PCA-MLR), the mean percentage contributions were 62.62% for mixed pyrogenic and petrogenic sources (e.g., unburned and combusted fossil fuels from fishing boats and vehicle engines, incomplete combustion, oil leakage), 20.68% for auto emission, and 16.7% for pyrogenic sources (fossil fuels and biomass combustion). According to the sediment risk assessment indices such as mean effects range-median quotient (M-ERM-Q), the ecological risk of multiple PAHs was low. Risk quotient (RQ) calculation of water samples suggested high ecological risk level for Benzo[a]anthracene (BaA), and low to moderate for other individual PAHs and ΣPAHs. The result of PAHs partitioning between sediment and water phases revealed that most PAHs prefer to accumulate in sediment. Sediments probably act as a secondary source for some PAHs in the oil collection and pumping station.

Source apportionment and health risk assessment of potentially toxic elements in road dust from urban industrial areas of Ahvaz megacity, Iran.

This study investigates the occurrence and spatial distribution of potentially toxic elements (PTEs) (Hg, Cd, Cu, Mo, Pb, Zn, Ni, Co, Cr, Al, Fe, Mn, V and Sb) in 67 road dust samples collected from urban industrial areas in Ahvaz megacity, southwest of Iran. Geochemical methods, multivariate statistics, geostatistics and health risk assessment model were adopted to study the spatial pollution pattern and to identify the priority pollutants, regions of concern and sources of the studied PTEs. Also, receptor positive matrix factorization model was employed to assess pollution sources. Compared to the local background, the median enrichment factor values revealed the following order: Sb > Pb > Hg > Zn > Cu > V > Fe > Mo > Cd > Mn > Cr ≈ Co ≈ Al ≈ Ni. Statistical results show that a significant difference exists between concentrations of Mo, Cu, Pb, Zn, Fe, Sb, V and Hg in different regions (univariate analysis, Kruskal-Wallis test p < 0.05), indicating the existence of highly contaminated spots. Integrated source identification coupled with positive matrix factorization model revealed that traffic-related emissions (43.5%) and steel industries (26.4%) were first two sources of PTEs in road dust, followed by natural sources (22.6%) and pipe and oil processing companies (7.5%). The arithmetic mean of pollution load index (PLI) values for high traffic sector (1.92) is greater than industrial (1.80) and residential areas (1.25). Also, the results show that ecological risk values for Hg and Pb in 41.8 and 9% of total dust samples are higher than 80, indicating their considerable or higher potential ecological risk. The health risk assessment model showed that ingestion of dust particles contributed more than 83% of the overall non-carcinogenic risk. For both residential and industrial scenarios, Hg and Pb had the highest risk values, whereas Mo has the lowest value.

Air pollution and cardiovascular and respiratory disease: Rationale and methodology of CAPACITY study.

BACKGROUND: Considering the high level of air pollution and its impact on health, we aimed to study the correlation of air pollution with hospitalization and mortality of cardiovascular (CVD) and respiratory diseases (ResD) (CAPACITY) to determine the effects of air pollutants on CVD and ResD hospitalizations and deaths in Isfahan, Iran. METHODS: Hourly levels of air pollutants including particulate matter (PM), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3), information of CVD and ResD admissions and death certificate were obtained respectively from Department of Environment (DOE), Iran, hospitals and cemetery. Time series and case-crossover model were used to find the impact of air pollutants. This paper only summarizes the descriptive findings of the CAPACITY study. RESULTS: The total number of hospitalized patients were 23781 in 2010 and 22485 in 2011. The most frequent cause of hospitalization and death was ischemic heart diseases in both years. While the mean annual levels of O3, CO, and PM10 were lower in 2011 than in 2010, NO2 and SO2 levels higher in 2011. In both years, PM10 was similarly increased during last month of fall, late spring and early summer. In 2011, the PM2.5 and PM10 monthly trend of change were similar. CONCLUSION: The CAPACITY study is one of the few large-scale studies that evaluated the effects of air pollutants on a variety of CVD and ResD in a large city of Iran. This study can provide many findings that could clarify the effects of these pollutants on the incidence and burden of both disease groups.

Heavy metals and polycyclic aromatic hydrocarbons in surface sediments of Karoon River, Khuzestan Province, Iran.

Karoon is the longest river in Iran and provides water for industries located along its banks, such as metal, petrochemical, and oil industries. It is also the source of drinking water for cities such as Ahwas, Abadan, and Khorramshahr. In this study, 34 and 18 surface sediment samples were collected and analyzed for heavy metals (Al, As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) and polycyclic aromatic hydrocarbons (PAHs). The measured concentrations of heavy metals were compared with US EPA sediment quality guidelines, and the results showed that Cu concentration was above the threshold effect level (TEL) in 65.67% of the samples and Hg concentration was above the effect range median (ERM) in some samples. The results revealed that Hg was severely enriched (5 < enrichment factor < 20) and classified in very high ecological risk index category. It is the major metallic contaminant in the study area. The total PAH concentrations ranged from 11.54-117,730 µg/kg, with the mean value of 7034.55 µg/kg dominated by lower molecular weight (LMW) PAHs. The total potentially carcinogenic PAHs (∑cPAHs) in sediment samples ranged from 2.09 to 31,930 µg/kg, indicating high carcinogenic potential of sediments in the study area. The total toxic equivalent (TEQ) values ranged from 1.06 to 7228.7 µg/kg. Maximum TEQ occurred in Abadan oil refinery station followed by Khorramshahr soap factory and Abadan petrochemical complex. Principal component analysis and cluster analysis also revealed the relationships between the studied parameters and identified their probable sources.

Genetic variation in the association of air pollutants with a biomarker of vascular injury in children and adolescents in Isfahan, Iran.

BACKGROUND: Some experimental studies revealed that exposure to air pollution increases the expression of tissue factor (TF) in atherosclerotic lesions. We aimed to investigate the role of TF +5466A>G (rs3917643) polymorphism in the association of air pollution on serum levels of TF as a biomarker of vascular injury in children. METHODS: This cross-sectional study was conducted among 110 children, consisting of 58 (52.8%) girls and 52 (47.2%) boys with a mean age of 12.7 ± 2.3 years, living in Isfahan, Iran. Enzyme-linked immunosorbent assay were used for measurement of serum TF. Genotype of +5466A>G (rs3917643) polymorphism was determined by the polymerase chain reaction-restriction length fragment polymorphism (PCR-RFLP) method. RESULTS: We identified 2 individuals with +5466AG genotype and 108 homozygous for the +5466A allele (no +5466GG homozygotes). The mean pollution standards index (PSI) value was at moderate level, the mean particular matter measuring up to 10 µm (PM(10)) was more than twice the normal level. Multiple linear regression analysis showed that after adjustment for confounding factors (weight status, dietary and physical activity pattern), serum TF level had significant relationship with PSI (beta: 0.55, SE: 0.07, p<0.000) and PM(10) (beta: 0.51, SE: 0.03, p=0.001). CONCLUSIONS: In spite of similar genetic polymorphism of TF, air pollutants might have an independent association with systemic inflammatory and coagulation responses. The harmful effects of air pollutants on the first stages of atherosclerosis in the pediatric age group should be underscored in primordial and primary prevention of chronic diseases.

The relationship of air pollution and surrogate markers of endothelial dysfunction in a population-based sample of children.

BACKGROUND: This study aimed to assess the relationship of air pollution and plasma surrogate markers of endothelial dysfunction in the pediatric age group. METHODS: This cross-sectional study was conducted in 2009-2010 among 125 participants aged 10-18 years. They were randomly selected from different areas of Isfahan city, the second large and air-polluted city in Iran. The association of air pollutants' levels with serum thrombomodulin (TM) and tissue factor (TF) was determined after adjustment for age, gender, anthropometric measures, dietary and physical activity habits. RESULTS: Data of 118 participants was complete and was analyzed. The mean age was 12.79 (2.35) years. The mean pollution standards index (PSI) value was at moderate level, the mean particular matter measuring up to 10 µm (PM10) was more than twice the normal level. Multiple linear regression analysis showed that TF had significant relationship with all air pollutants except than carbon monoxide, and TM had significant inverse relationship with ozone. The odds ratio of elevated TF was significantly higher in the upper vs. the lowest quartiles of PM10, ozone and PSI. The corresponding figures were in opposite direction for TM. CONCLUSIONS: The relationship of air pollutants with endothelial dysfunction and pro-coagulant state can be an important factor in the development of atherosclerosis from early life. This finding should be confirmed in future longitudinal studies. Concerns about the harmful effects of air pollution on children's health should be considered a top priority for public health policy; it should be underscored in primordial and primary prevention of chronic diseases.