We investigated temporal variations of ambient air pollutants and the influences of meteorological parameters on their concentrations using a robust method; convergent cross mapping; in Tehran ...(2012-2017). Tehran citizens were consistently exposed to annual PM
, PM
and NO
approximately 3.0-4.5, 3.5-4.5 and 1.5-2.5 times higher than the World Health Organization air quality guideline levels during the period. Except for O
, all air pollutants demonstrated the lowest and highest concentrations in summertime and wintertime, respectively. The highest O
concentrations were found on weekend (weekend effect), whereas other ambient air pollutants had statistically significant (P < 0.05) daily variations in which higher concentrations were observed on weekdays compared to weekend (holiday effect). Hourly O
concentration reached its peak at 3.00 p.m., though other air pollutants displayed two peaks; morning and late night. Approximately 45% to 65% of AQI values were in the subcategory of unhealthy for sensitive groups and PM
was the responsible air pollutant in Tehran. Amongst meteorological factors, temperature was the key influencing factor for PM
and PM
concentrations, while nebulosity and solar radiation exerted major influences on ambient SO
and O
concentrations. Additionally, there is a moderate coupling between wind speed and NO
and CO concentrations.
The coronavirus disease 2019 (COVID-19) emerged in Wuhan city, China, in late 2019 and has rapidly spread throughout the world. The major route of transmission of SARS-CoV-2 is in contention, with ...the airborne route a likely transmission pathway for carrying the virus within indoor environments. Until now, there has been no evidence for detection of airborne severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and this may have implication for the potential spread of the COVID-19. We investigated the air of patient rooms with confirmed COVID-19 in the largest hospital in Iran, on March 17, 2020. To collect the SARS-CoV-2 particles, ten air samples were collected into the sterile standard midget impingers containing 20 mL DMEM with 100 μg/mL streptomycin, 100 U/mL penicillin and 1% antifoam reagent for 1 h. Besides, indoor particle number concentrations, CO2, relative humidity and temperature were recorded throughout the sampling duration. Viral RNA was extracted from samples taken from the impingers and Reverse-Transcription PCR (RT-PCR) was applied to confirm the positivity of collected samples based on the virus genome sequence. Fortunately, in this study all air samples which were collected 2 to 5 m from the patients' beds with confirmed COVID-19 were negative. Despite we indicated that all air samples were negative, however, we suggest further in vivo experiments should be conducted using actual patient cough, sneeze and breath aerosols in order to show the possibility of generation of the airborne size carrier aerosols and the viability fraction of the embedded virus in those carrier aerosols.
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•To address the airborne transmission mode of SARS-CoV-2 air samples were collected in the largest hospital in Iran.•Our results indicated that all collected samples were negative in terms of the viral RNA.•We did not detect any positive readings 2 m from the patients' beds.
The main objectives of this study were (1) investigation of the temporal variations of ambient fine particulate matter (PM2.5) and ground level ozone (O3) concentrations in Tehran megacity, the ...capital and most populous city in Iran, over a 10-year period from 2006 to 2015, and (2) estimation of their long-term health effects including all-cause and cause-specific mortality. For the first goal, the data of PM2.5 and O3 concentrations, measured at 21 regulatory monitoring network stations in Tehran, were obtained and the temporal trends were investigated. The health impact assessment of PM2.5 and O3 was performed using the World Health Organization (WHO) AirQ+ software updated in 2016 by WHO European Centre for Environment and Health. Local baseline incidences in Tehran level were used to better reveal the health effects associated with PM2.5 and O3. Our study showed that over 2006–2015, annual mean concentrations of PM2.5 and O3 varied from 24.7 to 38.8 μg m−3 and 35.4 to 76.0 μg m−3, respectively, and were significantly declining in the recent 6 years (2010–2015) for PM2.5 and 8 years (2008–2015) for O3. However, Tehran citizens were exposed to concentrations of annual PM2.5 exceeding the WHO air quality guideline (WHO AQG) (10 μg m−3), U.S. EPA and Iranian standard levels (12 μg m−3) during entire study period. We estimated that long-term exposure to ambient PM2.5 contributed to between 24.5% and 36.2% of mortality from cerebrovascular disease (stroke), 19.8% and 24.1% from ischemic heart disease (IHD), 13.6% and 19.2% from lung cancer (LC), 10.7% and 15.3% from chronic obstructive pulmonary disease (COPD), 15.0% and 25.2% from acute lower respiratory infection (ALRI), and 7.6% and 11.3% from all-cause annual mortality in the time period. We further estimated that deaths from IHD accounted for most of mortality attributable to long-term exposure to PM2.5. The years of life lost (YLL) attributable to PM2.5 was estimated to vary from 67,970 to 106,706 during the study period. In addition, long-term exposure to O3 was estimated to be responsible for 0.9% to 2.3% of mortality from respiratory diseases. Overall, long-term exposure to ambient PM2.5 and O3 contributed substantially to mortality in Tehran megacity. Air pollution is a modifiable risk factor. Appropriate sustainable control policies are recommended to protect public health.
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•Long-term trends and health impacts of PM2.5 and O3 in Tehran were evaluated from 2006–2015.•Tehran citizens were exposed to annual PM2.5 approximately 2 to 4 times higher than the WHO guideline level at all times.•Annual mean O3 concentrations declined significantly over the whole period study.•In 2015, approximately 3800 deaths (> 10 per day) were attributable to long-term exposure to ambient PM2.5 in Tehran.
Abstract
Exposure to second-hand smoke (SHS) is prevalent in many countries, but the problem’s scope is poorly understood globally, especially in developing countries. We aimed to estimate SHS ...exposure and its national and subnational burden of diseases in Iran, the second-largest country in the Middle East, during 2009–2020. The burden of diseases from SHS was estimated as disability-adjusted life years (DALYs) for adolescents (10–18) year’s non-smokers. Using comparative risk assessment methodologies, the calculations were based on disease-specific relative risk estimates with national and subnational SHS exposure data, and the uncertainty and sensitivity analysis was performed. The results of study showed that the trend of exposure to SHS is increasing in Iran. The highest DALY was related to lower respiratory infection (LRI), asthma, and otitis media, respectively. The national average asthma burden (DALY/100,000) has increased from 17.4 (11.8_23.9) in 2009 to 21.3 (13.9_30) in 2020, LRI decreased from 25.8 (21.5_30.2) to 19.8 (16.7_23.1), and national average burden of otitis media (DALY/100,000) has increased from 3.1(1.9_4.6) to 3.9(2.4_5.6). The increasing trend of otitis media and asthma DALYs attributable to SHS exposure in Iran requires more attention from policymakers to protect the population.
Epidemiological evidence for the link between long-term exposure to air particulate matter (PM
2.5
) and occurrence of type 2 diabetes (T2D) is limited such that little is known about the effect of ...PM
2.5
exposure and adult T2D prevalence. Thus, the aim of this ecological study is to evaluate the contribution of ambient PM
2.5
exposure to the adult T2D prevalence in the large population of Iran. The study was conducted based on Iran’s large-scale cross-sectional surveilling non-communicable diseases (NCDs) risk factors (Timpka et al.
2015b
). A total of 31,050 participants were enrolled in three sequential processes of study using cluster random sampling. PM
2.5
data in the urban area of 31 provinces of Iran were acquired from Tehran Air Quality Control Company (AQCC) and the Department of Environment (DoE) of Iran during 2012–2016. Moreover, major and minor diabetes risk factors were considered; the Pearson correlation and a stepwise regression model were performed to estimate associations between risk factors and diabetes and prediabetes prevalence. The results showed T2D prevalence was more frequent among women (10.61%) than men (9.35%). A weak positive correlation was observed between PM
2.5
level and diabetes prevalence with a correlation coefficient of 0.275, although there was no significant association between PM
2.5
value and prediabetes prevalence. Moreover, none of the variables included in the regression model could predict the prevalence of diabetes and prediabetes. According to our study results, it can be suggested that investigating the association between PM
2.5
exposure and T2D prevalence at individual level may provide a better understanding of PM
2.5
exposure and the risk of T2D prevalence.
There is limited evidence for short-term association between mortality and ambient air pollution in the Middle East and no study has evaluated exposure windows of about a month prior to death. We ...investigated all-cause non-accidental daily mortality and its association with fine particulate matter (PM2.5), nitrogen dioxide (NO2), and the Air Quality Index (AQI) from March 2011 through March 2014 in the megacity of Tehran, Iran. Generalized additive quasi-Poisson models were used within a distributed lag linear modeling framework to estimate the cumulative effects of PM2.5, NO2, and the AQI up to a lag of 45 days. We further conducted multi-pollutant models and also stratified the analyses by sex, age group, and season. The relative risk (95% confidence interval (CI)) for all seasons, both sexes and all ages at lag 0 for PM2.5, NO2, and AQI were 1.004 (1.001, 1.007), 1.003 (0.999, 1.007), and 1.004 (1.001, 1.007), respectively, per inter-quartile range (IQR) increment (18.8 μg/m3 for PM2.5, 12.6 ppb for NO2, and 31.5 for AQI). In multi-pollutant models, the PM2.5 associations were almost independent from NO2. However, the RRs for NO2 were slightly attenuated after adjustment for PM2.5 but they were still largely independent from PM2.5. The cumulative relative risks (95% CI) per IQR increment reached maximum during the cooler months, including: 1.13 (1.06, 1.20) for PM2.5 at lag 0–31 (for females, all ages); 1.17 (1.10, 1.25) for NO2 at lag 0–45 (for males, all ages); and 1.13 (1.07, 1.20) for the AQI at lag 0–30 (for females, all ages). Generally, the RRs were slightly larger for NO2 than PM2.5 and AQI. We found somewhat larger RRs in females, age group >65 years of age, and in cooler months. In summary, positive associations were found in most models. This is the first study to report short-term associations between all-cause non-accidental mortality and ambient PM2.5 and NO2 in Iran.
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•First study to report the association between daily all-cause non-accidental mortality and ambient PM2.5 and NO2 in Iran.•Positive associations were found in most models.•Associations for PM2.5 and NO2 were almost independent from each other.•Effects were observed immediately, and persisted for several weeks.•Larger RRs were found in females, age group >65 years of age, and in cooler months.
Overall, the effects of PM2.5, NO2, and the AQI on all-cause non-accidental mortality in Tehran were immediate, and they increased steadily over a period of weeks.
Abstract
We estimated mortality and economic loss attributable to PM
2·5
air pollution exposure in 429 counties of Iran in 2018. Ambient PM
2.5
-related deaths were estimated using the Global ...Exposure Mortality Model (GEMM). According to the ground-monitored and satellite-based PM
2.5
data, the annual mean population-weighted PM
2·5
concentrations for Iran were 30.1 and 38.6 μg m
−3
, respectively. We estimated that long-term exposure to ambient PM
2.5
contributed to 49,303 (95% confidence interval (CI) 40,914–57,379) deaths in adults ≥ 25 yr. from all-natural causes based on ground monitored data and 58,873 (95% CI 49,024–68,287) deaths using satellite-based models for PM
2.5
. The crude death rate and the age-standardized death rate per 100,000 population for age group ≥ 25 year due to ground-monitored PM
2.5
data versus satellite-based exposure estimates was 97 (95% CI 81–113) versus 116 (95% CI 97–135) and 125 (95% CI 104–145) versus 149 (95% CI 124–173), respectively. For ground-monitored and satellite-based PM
2.5
data, the economic loss attributable to ambient PM
2.5
-total mortality was approximately 10,713 (95% CI 8890–12,467) and 12,792.1 (95% CI 10,652.0–14,837.6) million USD, equivalent to nearly 3.7% (95% CI 3.06–4.29) and 4.3% (95% CI 3.6–4.5.0) of the total gross domestic product in Iran in 2018.
Daily exposure to environmental phenols can lead to potential undesirable effects on the health of pregnant women and fetuses. The present study is aimed to evaluate the relationship between maternal ...urinary concentrations of phenols in pregnancy and anthropometric birth outcomes. The studied population comprised of 189 pregnant women participating in the Tehran Environment and Neurodevelopmental Disorders (TEND) prospective cohort study, which had been ongoing since March 2016 in some hospitals and health care delivery centers in Tehran, Iran. Concentrations of bisphenol-A, triclosan, 4-nonylphenol, and parabens were determined in spot urine samples of pregnant mothers in the first trimester. Weight, length, and head circumference at birth were also extracted from the mothers' delivery files. Multivariable linear regression was used to examine the relationship between log-concentrations of phenols and birth outcomes. When we analyzed all samples regardless of neonates' gender, none of the urinary concentrations of phenols were associated with weight and length at birth. Indeed, in sex-stratified adjusted models, one log-unit increase of butylparaben was related to a 283.6 g (95% CI: 23, 544) increase in boys' birth weight. Prenatal urinary concentration of triclosan and propylparaben was respectively related to a decrease of 4.8 cm (95% C: -8.5, −1.1) in boys' length and 0.9 cm (95%CI: -1.8, −0.04) in girls’ length. In the adjusted models for estimating the changes in head circumference, one log-unit increase of triclosan, methylparaben, and butylparaben led to a reduction of 1.6 cm (95% CI: -3.17, 0.03), increase of 0.8 cm (95% CI: -0.01, 1.6) and 0.7 cm (95% CI: 0.08, 1.4) in head circumference at birth respectively. Our results suggested that prenatal triclosan and parabens exposure might be associated with head circumference at birth. Furthermore, we observed a sexually dimorphic pattern between maternal triclosan and parabens exposure during pregnancy and fetal growth. However, these findings must be interpreted while taking into account the limitations of this study.
•Bisphenol-A, triclosan, and parabens were detected in the majority of urine samples of Iranian pregnant women.•First study on maternal urinary levels of environmental phenols and birth outcomes in Iran.•Prenatal concentrations of some phenols were associated with infants' birth size.
Exposure to lead can cause adverse health problems incorporating hypophosphatemia, heart and liver disease, cancers, neurological and cardiovascular diseases, central nervous disorders, and sensory ...disorders. This study investigated the blood lead level in the general Iranian population with environmental exposure to lead. In the presented systematic review and meta-analysis, the authors searched Iranian dataset, including Magiran, SID, Iranmedex, and Nopa, and the main dataset, comprising PubMed, Scopus, Embase, and Web of Science, all available articles until 12 January 2019, and extracting 55 studies (with 63 data for analysis) to a meta-analysis. A comprehensive meta-analysis software, pooled standard deviation, mean, sample size, and the utterly random effects model was analyzed in this study. The results showed that the overall mean BLL (95% CI) in total inquiries was 6.41 μg/dL (5.96 to 6.87). Besides, the results for gender and age subgroups were as follows: mean BLL, 6.47 μg/dL, 95% CI, 5.79, to 7.15, mean BLL, 6.44 μg/dL, 95% CI, 5.96, to 6.91, respectively. Conclusively the mean BLL in the Iranian population was higher than the recommended level by the US Centers for Disease Control and Prevention (CDC). Results indicated that the mean BLL in men and adults was more elevated than in women and children, respectively. Therefore, BLL monitoring and screening of the general Iranian population are is necessary to determine a reference value.
The present study aimed to provide a systematic review of studies on the prevalence of secondhand smoke (SHS) exposure in the Iran population as a serious indoor health hazard. A literature review of ...studies that considered SHS exposure, available in multiple electronic databases including Web of Science, PubMed, and Scopus published 2009–2020 in English and two Persian databases (SID and Magiran), was carried out following the PRISMA recommendations. A total of 55 studies were included based on the inclusion and exclusion criteria and the quality assessment. The results showed no specific decrease in the prevalence of exposure to secondhand smoke in Iran; however, it appeared that the exposure has been increasing. Distribution of studies in terms of age group revealed that most studies (38%) investigated adults (more than 18 years old), while 34% of the studies considered less than 18 years of age group and a single article considered infants (6–24 months). Based on the present study results, a large population of Iran was exposed to SHS. Moreover, based on Iran’s STEPs 2016 (Stepwise Non-communicable Diseases Risk Factors Survey in Iran) study, the overall prevalence of SHS exposure at home (57.5%) was higher than in workplaces (49.2%). The results of the present study recommended that protection measures should be comprehensive in terms of exposure places, and since the exposure prevalence in some provinces was higher than the others, it is especially important to consider the local measures and cultural aspects in SHS control programs.
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