Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Jan 15;10(1):292.
doi: 10.1038/s41598-019-56578-6.

Temporal variations of ambient air pollutants and meteorological influences on their concentrations in Tehran during 2012-2017

Fatemeh Yousefian  1   2 , Sasan Faridi  1   2 , Faramarz Azimi  3 , Mina Aghaei  1 , Mansour Shamsipour  4 , Kamyar Yaghmaeian  5 , Mohammad Sadegh Hassanvand  6
Affiliations

Temporal variations of ambient air pollutants and meteorological influences on their concentrations in Tehran during 2012-2017

Fatemeh Yousefian et al. Sci Rep. .

Abstract

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 PM2.5, PM10 and NO2 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 O3, all air pollutants demonstrated the lowest and highest concentrations in summertime and wintertime, respectively. The highest O3 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 O3 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 PM2.5 was the responsible air pollutant in Tehran. Amongst meteorological factors, temperature was the key influencing factor for PM2.5 and PM10 concentrations, while nebulosity and solar radiation exerted major influences on ambient SO2 and O3 concentrations. Additionally, there is a moderate coupling between wind speed and NO2 and CO concentrations.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1
The year-boxplot of PM10 (a), PM2.5 (b), NO2 (c), and SO2 (d) based on 24-hr concentrations and CO (e) and O3 (f) based on 8-hr concentrations in Tehran from 2012 to 2017. Black solid lines and black long-dash lines represent the World Health Organization air quality guideline and Iranian standard levels, respectively.
Figure 2
Figure 2
Temporal variations of ambient PM10, PM2.5 (a,c) and NO2, O3, SO2, CO (b,d) concentrations in Tehran during the study period (2012–2017).
Figure 3
Figure 3
The AQI-subcategories’ figures (left) and contribution of each air pollutant in AQI values (right) in Tehran during the study period from 2012 to 2017.
Figure 4
Figure 4
Exemplary CCM test results to show the causality between MPs and the concentrations of ambient PM2.5 (a), PM10 (b), NO2 (c), CO (d), O3 (e), and SO2 (f) in Tehran.
See this image and copyright information in PMC

References

    1. Burnett R, et al. Global estimates of mortality associated with long-term exposure to outdoor fine particulate matter. Proceedings of the National Academy of Sciences. 2018;115:9592–9597. doi: 10.1073/pnas.1803222115. - DOI - PMC - PubMed
    1. Brook RD, Newby DE, Rajagopalan S. The global threat of outdoor ambient air pollution to cardiovascular health: time for intervention. JAMA cardiol. 2017;2:353–354. doi: 10.1001/jamacardio.2017.0032. - DOI - PubMed
    1. Faridi S, et al. Long-term trends and health impact of PM 2.5 and O 3 in Tehran, Iran, 2006–2015. Environment international. 2018;114:37–49. doi: 10.1016/j.envint.2018.02.026. - DOI - PubMed
    1. Amini H, et al. Spatiotemporal description of BTEX volatile organic compounds in a Middle Eastern megacity: Tehran study of exposure prediction for environmental health research (Tehran SEPEHR) Environmental pollution. 2017;226:219–229. doi: 10.1016/j.envpol.2017.04.027. - DOI - PubMed
    1. Givehchi R, Arhami M, Tajrishy M. Contribution of the Middle Eastern dust source areas to PM10 levels in urban receptors: Case study of Tehran, Iran. Atmospheric environment. 2013;75:287–295. doi: 10.1016/j.atmosenv.2013.04.039. - DOI

Publication types