Introduction: NO₂ and SO₂ as gaseous air pollutants are involved in many global air accidents, and are respiratory tract irritants that can cause numerous health effects in humans. Therefore, due to the necessity of studies in this field and the absence of any similar study in the city of Hamadan, the aim of this study was quantification of health effects attributed to NO₂ and SO₂ in Hamadan city of Iran during years 2014 and 2015.

Methods: This was a cross-sectional study. Primarily, required criteria pollutants and meteorological data were obtained from the environmental protection agency and meteorological agency of Hamadan city, respectively. The obtained data were validated using the World Health Organization (WHO) criteria. Required statistical indices were calculated and according to baseline incidence, relative risk and exposed populations, the different effects of pollutants were assessed.

Results: According to the results, the average annual concentration of NO₂ and SO₂ was 1.7 and 1.6 times more than the standard, respectively. With central relative risk, the estimated attributed portion for total mortality attributed to NO₂ and SO₂ was 1.74 and 0.92, respectively, which is equal to death of 51.9 and 27.3 individuals during years 2014 and 2015, respectively.

Conclusion: As a result, it should be stated that most of the adverse health effects attributed to SO₂ and NO₂ were observed in concentration ranges from 20 to 49 and 40 to 89 micrograms per cubic meter, respectively. This indicated that the concentration distribution of NO₂ was wider than SO₂. It can also be concluded that investigated pollutants (NO₂ and SO₂) had significant adverse effects on the residents of Hamadan city and before further increase in the effects, preventive measures should be taken by relevant authorities