Cause-specific mortality attributed to fine particles in Mashhad, Iran (2013-2017)

Introduction: This study aimed to determine the number of all-cause, lung cancer, chronic obstructive pulmonary disease (COPD), ischemic heart disease (IHD), and stroke deaths due to exposure to PM2.5 in Mashhad during March 2013-March 2017 using the AirQ+ model. Materials and methods: Hourly concentrations of fine particulate matter were obtained from Department of Environment (DOE) of Iran, and validated according to APHEKOM study and WHO’s criteria. Baseline incidence (BI) values for all-cause, COPD, lung cancer, IHD and stroke mortality was obtained from Ministry of Health and Medical Education. Results: The annual average of (±SD) was determined for all four years and the average four- year were 36.07 (± 26.93), 27.29 (± 13.24), 30.53 (± 13.82), 30.14 (± 15.94), and 31.01 (± 10.22) μg / m3, respectively. The averages of PM2.5 concentrations during the cold months of years was higher than those in the warm months. Calculating the daily air quality index (AQI) indicated that only few days (48 days) during this period of time ( 4 years ) had a “standard” air quality and a concentration lower that 12.5 μg / m3. The total number of deaths in all the four years was 4457 cases. Furthermore, the total number of COPD, lung cancer, IHD, and stroke mortality was 146, 142, 5263, and 2608 cases, respectively. The trend of death numbers did not follow a specific direction, and some fluctuations can be observed. Conclusion: Due to the considerable health effects of the poor air quality in Mashhad, controlling actions should be implemented to reduce the levels of air pollution.