variations of pm2.5 and health risk assessment in the city of mashhad during 2010-2018

Background: air pollution stands as a significant environmental threat impacting human health across the globe, encompassing both developed and developing nations. this study aimed to survey the temporal variations of pm2.5 and gauge its potential health effects in the city of mashhad over the period of 2010-2018.methods: this cross-sectional study was carried out among the residents of mashhad city. pm2.5 concentration data spanning the years 2008-2019 were collected and subjected to analysis using excel and airq software.results: the results indicate that the highest concentration of pm2.5 was associated with the year 2010, while the lowest concentration was observed in 2015. the analytical findings demonstrated that for each 10 μg/m3 increase in pm2.5 concentrations, the relative risk for total mortality increased by 10.47%. furthermore, based on the air quality index (aqi) results, 2010 exhibited the most adverse condition in terms of pm2.5 concentrations in mashhad city.conclusion: in general, long-term exposure to ambient pm2.5 significantly contributed to mortality in the megacity of mashhad. as air pollution is a modifiable risk factor, it is advisable to implement sustainable control policies to protect public health.