Evaluation of air quality in Turkey according to the new limit value recommendations of the World Health Organization

Particulate matter (PM 2.5 and PM 10 ), ozone (O 3 ), nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ), and carbon monoxide (CO) are air pollutants that must be constantly monitored in ambient air. Air quality is not only a standard to be followed but also a requirement for a healthy life and environment. The World Health Organization (WHO) stated that 99% of the entire world population lives in cities that do not comply with the recommended air quality standards, and in 2021 it updated its limit value recommendations to be more stringent. This study aims to determine whether the pollutant concentrations ​​of PM 10 , PM 2.5 , SO 2 , and NO 2 measured in air quality monitoring stations in Turkey in 2020 and 2021 comply with the new WHO limit value recommendations. Air quality in Turkey was evaluated according to the new WHO limit value recommendations, using data downloaded for 2020 and 2021 from the National Air Quality Monitoring Network operated by the Turkish Ministry of Environment, Urbanization, and Climate Change. As a result of the study, for 2020 the rates of stations where the annual average PM 2.5 , NO 2, and PM 10 limit values were exceeded were determined as 81%, 63%, and 40%, respectively. The rates of stations where the annual average PM 2.5 , NO 2 and PM 10 limit values were exceeded in 2021 were found to be 19%, 37% and 60%, respectively. In addition, the stations with the highest measurements of PM 10 , PM 2.5 , SO 2 , and NO 2 pollutants were also determined in the study. It can be said that the air quality in the regions where the stations measuring above the WHO limit values ​​are at a level that will pose a threat to public health.