Assessing capabilities of conducted ambient air pollution health effects studies in 22 Eastern Mediterranean countries to adopt air quality standards: a review

Purpose

The Eastern Mediterranean Region (EMR) countries suffer from exposure to high levels of ambient air pollutants due to dust storms and have unique climatic as well as topographic and socio-economic conditions which lead to adverse health effects on humans. The purpose of the review was to evaluate the quantity and quality of published articles on air pollution and health-based studies in 22 EMR countries to determine if they can be applied to adopting air quality standards.

Methods

We designed a review based on a broad search of the literature in the Scopus, PubMed, and web of science (WOS) databases published from January 1, 2000, to January 2, 2022, using combinations of the following relevant terms: air pollution, health, and EMR countries. The generic eligibility criteria for this review were based on the population, exposure, comparator, outcome, and study design (PECOS) statement.

Results

The search results showed that following the PRISMA approach, of 2947 identified articles, 353 studies were included in this review. The analysis of the types of studies showed that about 70% of the studies conducted in EMR countries were Health Burden Estimation studies (31%), Ecological and time trend ecological studies (23%), and cross-sectional studies (16%). Also, researchers from Iran participated in the most published relevant studies in the region 255 (~ 63%) and just 10 published documents met all the PECOS criteria.

Conclusion

The lack of sufficient studies which can meet the PECOS appraising criteria and the lack of professionals in this field are some of the issues that make it impossible to use as potential documents in the WHO future studies and adopt air quality standards.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40201-023-00862-1.

Impact of short-term air pollution exposure on acute coronary syndrome in two cohorts of industrial and non-industrial areas: A time series regression with 6,000,000 person-years of follow-up (ACS - Air Pollution Study)

BACKGROUND

There is a lack of studies directly comparing the effect of air pollution on acute coronary syndrome (ACS) occurrence in industrial and non-industrial areas.

OBJECTIVES

A comparison of association of air pollution exposure with ACS in two cohorts of industrially different areas.

MATERIALS AND METHODS

The study covered 6,000,000 person-years of follow-up and five pollutants between 2008 and 2017. A time series regression analysis with 7-lag was used to assess the effects air pollution on ACS.

RESULTS

A total of 9046 patients with ACS were included in the analysis, of whom 3895 (43.06%) had ST-elevation myocardial infarction (STEMI) - 45.39% from non-industrial area, and 42.37% from industrial area; and 5151 (56.94%) had non-ST-elevation myocardial infarction (NSTEMI) - 54.61% from non-industrial area and 57.63% from industrial area. The daily concentrations of PM_2.5, PM₁₀, NO₂, SO₂, CO were higher in industrial than in non-industrial area (P < 0.001). In non-industrial area, an increase of 10 μg/m³ of NO₂ concentration (Odds Ratio (OR) = 1.126, 95%CI = 1.009-1.257; P = 0.034, lag-0) and an increase of 1 mg/m³ in CO concentration (RR = 1.055, 95%CI = 1.010-1.103; P = 0.017, lag-0) were associated with an increase in the number of hospitalization due to NSTEMI (for industrial area increase of 10 μg/m³ in NO₂ (OR = 1.062, 95%CI = 1.020-1.094; P = 0.005, lag-0), SO₂ (OR = 1.061, 95%CI = 1.010-1.116; P = 0.018, lag-4), PM₁₀ (OR = 1.010, 95%CI = 1.001-1.030; P = 0.047, lag-6). In STEMI patients in industrial area, an increased hospitalization was found to be associated with an increase of 10 μg/m³ in SO₂ (OR = 1.094, 95%CI = 1.030-1.162; P = 0.002, lag-1), PM_2.5 (OR = 1.041, 95%CI = 1.020-1.073; P < 0.001, lag-1), PM₁₀ (OR = 1.030, 95%CI = 1.010-1.051; P < 0.001, lag-1). No effects of air pollution on the number of hospitalization due to STEMI were noted from non-industrial area.

CONCLUSION

The risk of air pollution-related ACS was higher in industrial over non-industrial area. The effect of NO₂ on the incidence of NSTEMI was observed in both areas. In industrial area, the effect of PMs and SO₂ on NSTEMI and STEMI were also observed. A clinical effect was more delayed in time in patients with NSTEMI, especially after exposure to PM₁₀. Chronic exposure to air pollution may underlie the differences in the short-term effect between particulate air pollution impact on the incidence of STEMI.

Impact of temperature and air pollution on cardiovascular disease and death in Iran: A 15-year follow-up of Tehran Lipid and Glucose Study

In this, the first study to be conducted in the Middle East and North Africa (MENA) on the subject, we examined the impact of temperature and air pollution on cardiovascular disease (CVD) and all-cause mortality. The Tehran Lipid and Glucose Study followed 9731 participants, aged ≥30years (men=4409), during the period 1999-2014, reporting 1350 CVDs (men=796) and 725 deaths (men=447). Air pollution level was measured using the air quality index (AQI). Data were analyzed using the distributed lag nonlinear model, with 30°C temperature and AQI=50 minimum risk values, as the relative risks' (RR) reference values. Although for the whole sample, no significant effect of air pollution was observed on CVD, for the under 60year olds, two significant peaks occurred in AQI=180 at lags 2 and 6days (RR=1.94, 95% CI: 1.02-3.67 and 2.06, 95% CI: 1.09-3.88, respectively). Temperature had no significant effect on CVD, yet the closest case to significance happened at 36°C and lag 5days (RR=1.43, 95% CI: 0.97-2.11), for ages ≥60y. The largest significant effects of air pollution on death, occurred in AQI=180 and lag 1day (RR=2.40, 95% CI: 1.0.-5.59 and 3.29, 95% CI: 1.15-9.36, for the whole sample and the <60year olds, respectively). Interestingly, for those aged over 60years, the peak belonged to AQI=180 and lag 7days (RR=2.16, 95% CI: 1.11-4.19). Regarding the effect of temperature on death among the whole sample, the highest risk was for 6°C and lag 0 (RR=3.91, 95% CI: 1.12-13.61). For the ≥60year olds, it occurred in 9⁺ and lag 0 (RR=6.81, 95% CI: 1.69-27.44), though notably, the peak went to -3°C and lag 3 (RR=5.69, 95% CI: 1.12-28.87), for those aged <60years. Overall, the effect of low temperature on death had the highest risk, for the over 60-year-olds, without any lag. Moreover, the <60-year-olds were the most vulnerable group to air pollution with a one day lag, in terms of mortality risk.

The burden of air pollution and weather condition on daily respiratory deaths among older adults in China, Jinan from 2011 to 2017

The health effects of short-term exposure to air pollutants on respiratory deaths and its modifiers such as meteorological indexes have been widely investigated. However, most of the previous studies are limited to single pollutants or total respiratory deaths, and their findings are inconsistent.To comprehensively examine the short-term effects of air pollutants on daily respiratory mortality.Our analysis included 16,931 nonaccidental respiratory deaths (except lung cancer and tuberculosis) among older adults (>65 years) from 2011 to 2017 in Jinan, China. We used a generalized additive Poisson models adjusted for meteorology and population dynamics to examine the associations between air pollutants (particulate matter with an aerodynamic diameter of b2.5μm [PM2.5], particulate matter with an aerodynamic diameter of b10μm [PM10], SO2, NO2, O3) and daily mortality for the total patients, males, females, chronic airway diseases, pneumonia patients, and rest patients in Jinan.Outdoor air pollution was significantly related to mortality from all respiratory diseases especially from chronic airway disease in Jinan, China. The effects of air pollutants had lag effects and harvesting effects, and the effects estimates usually reached a peak at lag 1 or 2 day. An increase of 10 μg/m or 10 ppb of PM2.5, PM10, SO2, NO2, and O3 corresponds to increments in mortality caused by chronic airway disease of 0.243% (95% confidence interval [CI]: -0.172-0.659) at lag 1 day, 0.127% (95% CI: -0.161-0.415) at lag 1 day, 0.603% (95% CI: 0.069-1.139) at lag 3 day, 0.649% (95% CI: -0.808-2.128) at lag 0 day and 0.944% (95% CI: 0.156-0.1598) at lag 1 day, respectively. The effects of air pollutants were usually greater in females and varied by respiratory subgroups. Spearman correlation analysis suggested that there was a significant association between meteorological indexes and air pollutants.Sex, age, temperature, humidity, pressure, and wind speed may modify the short-term effects of outdoor air pollution on mortality in Jinan. Compared with the other pollutants, O3 had a stronger effect on respiratory deaths among the elderly. Moreover, chronic airway diseases were more susceptible to air pollution. Our findings provided new evidence for new local environmental and health policies making.

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.

Temporal trends in respiratory mortality and short-term effects of air pollutants in Shenyang, China

Short-term exposures to air pollution are associated with acute effects on respiratory health. This study aimed to describe 10-year temporal trends in respiratory mortality in the urban areas of Shenyang, China, according to gender and age and estimate the effects of air pollution on respiratory diseases (ICD-10J00-J99) and lung cancer (ICD-10 C33-C34) using a case-crossover design. During the study period 2013-2015, the exposure-response relationship between ambient air pollutants and mortality data was fitted by a quasi-Poisson model. Age-standardized mortality rates for a combined number of respiratory diseases and for lung cancer declined in Shenyang; however, death counts increased with aging. Deaths from respiratory diseases increased by 4.7% (95% CI, 0.00-9.9), and lung cancer mortality increased by 6.5% (95% CI, 1.2-12.0), both associated with a 10 μg/m³ increase in exposure to particulate matter < 2.5 μg in diameter (PM2.5). Moreover, males in Shenyang's urban areas were more susceptible to the acute effects of PM2.5 and SO₂ exposure; people aged ≥ 65 years had a high susceptibility to ozone, and those aged < 65 years were more susceptible to other air pollutants. These results provided an updated estimate of the short-term effects of air pollution in Shenyang. Since population aging is also associated with increasing mortality from respiratory diseases and lung cancer, reinforcing air quality control measures and health-promoting behaviors is urgent and necessary in Shenyang.

Associations of short-term exposure to ambient air pollutants with emergency ambulance calls for the exacerbation of essential arterial hypertension

We investigated the association between daily emergency ambulance calls (EAC) for elevated blood pressure that occurred during the time intervals of 8:00-13:59, 14:00-21:59, and 22:00-7:59, and exposure to CO, PM₁₀, and ozone. We used Poisson regression to explore the association between the risk of EAC and short-term variation of pollutants, adjusting for seasonality and weather variables. Before noon, the risk was associated with an interquartile range (IQR) (7.9 μg/m³) increase in PM₁₀ at lag 2-4 days below the median (RR = 1.08, p = 0.031) and with an IQR (0.146 mg/m³) increase in CO at lag 6-7 below the median (RR = 1.05, p = 0.028). During 14:00-21:59, the risk was associated with an IQR (18.8 μg/m³) increase in PM₁₀ on the previous day below the median (RR = 1.04, p = 0.031). At night, EAC were negatively affected by lower O₃ (lag 0-2) below the median (per IQR decrease RR = 1.10, p = 0.018) and a higher PM₁₀ at lag 0-1 above the median for the elderly (RR = 1.07, p = 0.030).

Associations of Short-Term and Long-Term Exposure to Ambient Air Pollutants With Hypertension

Hypertension is a major disease of burden worldwide. Previous studies have indicated that air pollution might be a risk factor for hypertension, but the results were controversial. To fill this gap, we performed a meta-analysis of epidemiological studies to investigate the associations of short-term and long-term exposure to ambient air pollutants with hypertension. We searched all of the studies published before September 1, 2015, on the associations of ozone (O 3 ), carbon monoxide (CO), nitrogen oxide (NO 2 and NO X ), sulfur dioxide (SO 2 ), and particulate matter (PM 10 and PM 2.5 ) with hypertension in the English electronic databases. A pooled odds ratio (OR) for hypertension in association with each 10 μg/m 3 increase in air pollutant was calculated by a random-effects model (for studies with significant heterogeneity) or a fixed-effect model (for studies without significant heterogeneity). A total of 17 studies examining the effects of short-term (n=6) and long-term exposure (n=11) to air pollutants were identified. Short-term exposure to SO 2 (OR=1.046, 95% confidence interval [CI]: 1.012–1.081), PM 2.5 (OR=1.069, 95% CI: 1.003–1.141), and PM 10 (OR=1.024, 95% CI: 1.016–1.032) were significantly associated with hypertension. Long-term exposure (a 10 μg/m 3 increase) to NO 2 (OR=1.034, 95% CI: 1.005–1.063) and PM 10 (OR=1.054, 95% CI: 1.036–1.072) had significant associations with hypertension. Exposure to other ambient air pollutants (short-term exposure to NO 2 , O 3 , and CO and long-term exposure to NO x , PM 2.5 , and SO 2 ) also had positive relationships with hypertension, but lacked statistical significance. Our results suggest that short-term or long-term exposure to some air pollutants may increase the risk of hypertension.

Ambient PM2.5 and Risk of Hospital Admissions: Do Risks Differ for Men and Women?

BACKGROUND

While strong evidence exists for associations between fine particles (PM2.5) and health, less is known about whether associations differ by sex.

METHODS

We used Bayesian hierarchical modeling to estimate associations between PM2.5, based on ambient monitors, and risk of cause-specific cardiovascular and respiratory hospitalizations for about 12.6 million Medicare beneficiaries (>65 years) residing in 213 US counties for 1999-2010.

RESULTS

Point estimates were higher for women than men for almost all causes of hospitalization. PM2.5 risks were higher for women than men for respiratory tract infection, cardiovascular, and heart rhythm disturbance admissions. A 10 μg/m(3) increase in same-day PM2.5 was associated with a 1.13% increased risk of heart rhythm disturbance admissions for women (95% posterior interval [PI]: 0.63%, 1.63%), and 0.03% for men (95% PI: -0.48%, 0.55%). Differences remained after stratification by age and season.

CONCLUSIONS

Women may be more susceptible to PM2.5-related hospitalizations for some respiratory and cardiovascular causes.

Modeling of the relationship between the environmental air pollution, clinical risk factors, and hospital mortality due to myocardial infarction in Isfahan, Iran

Background:

This study aimed to determine the relationship between the environmental factor, clinical risk factors, and individual variables with mortality due to acute myocardial infarction (MI) in Isfahan.

Materials and Methods:

This cross-sectional study was performed between April 2012 and March 2013. The data on the patients’ mortality due to MI in Isfahan were obtained from the MI National Registry. The international classification system (ICD10: I21-I22) was used to diagnose MI. The air quality indicators and environmental variables were used to measure the air pollution. Multilevel logistic regression in the Stata software was used to determine the factors associated with mortality in patients and odds ratios (ORs) were calculated.

Results:

Six hundred eleven patients with MI were studied during 1-year. 444 (72.2%) patients were male and the rest were female. 4.7% of the patients died due to MI. The mean age at MI incidence was 62.2 ± 13 years. Of the air pollution parameters, PM₁₀ had the maximum mean concentration (49.113 ppm), followed by NO_X, NO, NO₂, CO, SO₂, and O₃. The adjusted OR of mortality was derived 2.07 (95% CI: 1.5-2.85) for right bundle branch block, 1.5 (95% CI: 1.3-1.7) for ST-segment elevation MI, 1.84 (95% CI: 1.13-3) for age, 1.06 (95% CI: 1.01-1.20) for CO, 1.1 (95% CI: 1.03-1.30) for O₃, and 1.04 (95% CI: 1.01-1.4) for SO₂, all of which were considered as the risk factors of mortality. However, OR of mortality was 0.79 for precipitation (95% CI: 0.74-0.84) and 0.52 for angioplasty (95% CI: 0.4-0.68) were considered as protective factors of mortality. The individual characteristics including age, history of MI in the immediate family, hypertension, and diabetes were significantly associated with mortality from MI. The indices of air pollution including SO₂, CO, O₃, and environmental factors such as the precipitation and temperature were the determinants of mortality in patients with MI.

Conclusion:

With regards to the factors associated with mortality from MI reported in this study, air pollution and environmental factors, in addition to the risk factors and predictive factors, should be particularly addressed to control the mortality from MI.

Trends in health burden of ambient particulate matter pollution in Iran, 1990-2010: findings from the Global Burden of Disease study 2010

This paper aims to report the assessment of trends in deaths and disability-adjusted life years (DALYs) attributed to ambient particulate matter (PM) pollution from 1990 to 2010 by sex and age in Iran. We used the data of the Global Burden of Disease (GBD) 2010 Study, and then we extracted its data on Iran for the years 1990, 2005, and 2010. The proportion of deaths and the DALYs caused by specific risk factors were assessed by using the comparative risk assessment and calculating the attributed burden of exposure level to each risk factor compared with the theoretical minimum level of risk exposure. Uncertainties in distribution of exposure, relative risks, and relevant outcomes calculation were disseminated into the estimates of the attributable deaths and DALYs. We found that the age-standardized death rate attributed to ambient PM pollution decreased to 27.90 cases per 100,000 populations from 1990 to 2010 [86, 95% uncertainty interval (UI) 76-97 to 62; 95% UI 54-71 per 100,000 populations, respectively]. This was mainly because of greater decrease in cardiovascular diseases (CVDs) than in the other diseases attributed to PM pollution. Despite a decrease in the total DALYs and mortality rate attributed to PM pollution, the death percent increased by 6.94%, 95% UI 6.06-7.90% from 1990 to 2010. The number of the DALYs and death in age groups of more than 70 years increased in 2010 compared to that in 1990. The median percent change of the DALYs and death for all age groups shows that the DALYs and death increased by 6% (95% UI 8-19%) and 45% (95% UI 30-60%), respectively, in 2010 in comparison to that in 1990. The increase in the DALYs and mortality attributable to PM pollution emphasizes the necessity of the effective interventions for improving air quality, as well as for increasing the public awareness to reduce the exposure of vulnerable age groups to PM pollution.

Land use regression models to estimate the annual and seasonal spatial variability of sulfur dioxide and particulate matter in Tehran, Iran

The Middle Eastern city of Tehran, Iran has poor air quality compared with cities of similar size in Europe and North America. Spatial annual and seasonal patterns of SO2 and PM10 concentrations were estimated using land use regression (LUR) methods applied to data from 21 air quality monitoring stations. A systematic algorithm for LUR model building was developed to select variables based on (1) consistency with a priori assumptions about the assumed directions of the effects, (2) a p-value of <0.1 for each predictor, (3) improvements to the leave-one-out cross-validation (LOOCV) R(2), (4) a multicollinearity index called the variance inflation factor, and (5) a grouped (leave-25%-out) cross-validation (GCV) for final model. In addition, several new predictive variables and variable types were explored. The annual mean concentrations of SO2 and PM10 across the stations were 38 ppb and 100.8 μg/m(3), respectively. The R(2) values ranged from 0.69 to 0.84 for SO2 models and from 0.62 to 0.67 for PM10 models. The LOOCV and GCV R(2) values ranged, respectively, from 0.40 to 0.56 and 0.40 to 0.50 for the SO2 models; they were 0.48 to 0.57 and 0.50 to 0.55, respectively, for the PM10 models. There were clear differences between the SO2 and PM10 models, but the warmer and cooler season models were consistent with the annual models for both pollutants. Although there was limited similarity between the SO2 and PM10 predictive variables, measures of street density and proximity to airport or air cargo facilities were consistent across both pollutants. In 2010, the entire population of Tehran lived in areas where the World Health Organization guidelines for 24-hour mean SO2 (7 ppb) and annual average PM10 (20 μg/m(3)) were exceeded.

Evidence on vulnerability and susceptibility to health risks associated with short-term exposure to particulate matter: a systematic review and meta-analysis

Although there is strong evidence that short-term exposure to particulate matter is associated with health risks, less is known about whether some subpopulations face higher risks. We identified 108 papers published after 1995 and summarized the scientific evidence regarding effect modification of associations between short-term exposure to particulate matter and the risk of death or hospitalization. We performed a meta-analysis of estimated mortality associations by age and sex. We found strong, consistent evidence that the elderly experience higher risk of particular matter--associated hospitalization and death, weak evidence that women have higher risks of hospitalization and death, and suggestive evidence that those with lower education, income, or employment status have higher risk of death. Meta-analysis showed a statistically higher risk of death of 0.64% (95% confidence interval (CI): 0.50, 0.78) for older populations compared with 0.34% (95% CI: 0.25, 0.42) for younger populations per 10 μg/m3 increase of particulate matter with aerodynamic diameter ≤10 μm. Women had a slightly higher risk of death of 0.55% (95% CI: 0.41, 0.70) compared with 0.50% (95% CI: 0.34, 0.54) for men, but these 2 risks were not statistically different. Our synthesis on modifiers for risks associated with particulate matter can aid the design of air quality policies and suggest directions for future research. Studies of biological mechanisms could be informed by evidence of differential risks by population, such as by sex and preexisting conditions.

Health impact assessment of air pollution in Shiraz, Iran: a two-part study

We aimed to assess health-impacts of short-term exposure to the air pollutants including PM10, SO2, and NO2 in Shiraz, Iran in a two-part study from 2008 to 2010. In part I, local relative risks (RRs) and baseline incidences (BIs) were calculate using generalized additive models. In part II, we estimated the number of excess hospitalizations (NEHs) due to cardiovascular diseases (CDs), respiratory diseases (RDs), respiratory diseases in elderly group (RDsE-people older than 65 years old), and chronic obstructive pulmonary diseases (COPDs) as a result of exposure to air pollutants using AirQ model, which is proposed approach for air pollution health impact assessment by World Health Organization. In part I, exposure to increase in daily mean concentration of PM10 was associated with hospitalizations due to RDs with a RR of 1.0049 [95% confidence interval (CI), 1.0004 to 1.0110]. In addition, exposure to increase in daily mean concentration of SO2 and NO2 were associated with hospitalizations due to RDsE and COPDs with RRs of 1.0540 [95% CI, 1.0050 to 1.1200], 1.0950 [95% CI, 1.0700 to 1.1100], 1.0280 [95% CI, 1.0110 to 1.0450] and 1.0360 [95% CI, 1.0210 to 1.0510] per 10 μg/m3 rise of these pollutants, respectively. In part II, the maximum NEHs due to CDs because of exposure to PM10 were in 2009-1489 excess cases (ECs). The maximum NEHs due to RDs because of exposure to PM10 were in 2009-1163 ECs. Meanwhile, the maximum NEHs due to RDsE and COPDs because of exposure to SO2 were in 2008, which are 520 and 900 ECs, respectively. In conclusion, elevated morbidity risks were found from acute exposure to air pollutants.