On the concentration of radon in a polluted city of the Middle East: An insight into its association with PM levels, air properties, and risk assessment

Abstract

This study was conducted in Ahvaz city, where the concentrations of radon and airborne particles in 10, 2.5, and 1 micrometers, along with meteorological parameters were measured. The measurements were performed in three educational and therapeutic sampling points at both ground and underground levels during cold and hot seasons. The results showed that in 3.17% of the samples, the concentration of radon exceeded the permissible limit recommended by the Environmental Protection Agency (EPA). Factors affecting the increase of radon concentration in indoor air included cold season, underground sampling points, the number of doors and windows as air dilution factor and air exchange, air pressure, and air humidity. The concentration of particles in the air did not have any effect on radon in the indoor air. The annual effective dose of exposure to radon (DR), the annual effective dose of lung (DE), and the risk of lung cancer cases (LCC) during both cold and hot seasons and at ground and underground levels were lower than the permissible values recommended by the International Committee on Radiological Protection (ICRP). We concluded that the increase of particles is neither the cause nor the source of increased indoor air radon. The findings of the present investigation recommend controlling physical indoor air parameters particularly temperature and relative humidity by proper ventilation systems to mitigate the impact of radon exposure on inhabitants.