The burden of cardiovascular and respiratory diseases attributed to ambient sulfur dioxide over 26 years.

INTRODUCTION: Developing countries, particularly those with a rapid development, are experiencing increasing pollution by sulfur dioxide (SO2). Despite the considerable SO2 exposure effect on health, there is little evidence regarding this fact in Iran, as one of the largest oil and gas producing countries in the world. The present study, therefore, was designed to investigate the burden of cardiovascular and respiratory diseases attributed to the SO2 exposure in Iran, over a 26-year period.
MATERIALS AND METHODS: All measured SO2 levels were collected from 92 air quality monitoring stations (AQMSs) in 29 cities, during 1996-2013. Since the study years were from 1990 to 2015, and also due to missing data at existing stations, the spatiotemporal model was used to estimate the exposure to this gas during this period. To calculate the burden of cardiovascular and respiratory diseases, the population attributable fraction (PAF) value was calculated, and the SO2-attributed mortality and years of life lost (YLL) were determined per province, and in the whole country.
RESULTS: The results of this study showed that the SO2 concentration was increased from 22.00 ppb (7.69-67.28) in 1990 to 27.81 ppb (9.88-82.27), in 2015. The lowest annual value of 11.53 ppb (4.68-32.06) and the highest value of 45.11 ppb (16.58-1226) were estimated at 2004 and 1997, respectively. There was a sinusoidal trend in the gas concentration changes. The highest occurrence of SO2-attributed deaths due to cardiovascular and respiratory diseases were 0.080 (0.024-0.168) and 0.076 (0.026-0.165), and the lowest levels were 0.017 (0.004-0.044) and 0.047 (0.017-0.124), respectively.
CONCLUSIONS: According to the results in our country, the SO2 trend was sinusoidal during 26 years, with a recurrent rise occurring after each declining period. It is recommended to design the sustainable national method policies and programs with the continuous evaluation and modification for the reduction of fossil fuel consumption and further implementation in the use of clean energy. © Springer Nature Switzerland AG 2020.