Residential radon exposure and seasonal variation in the countryside of southeastern Brazil

• Published in: Environmental monitoring and assessment 2020-08, Vol.192 (8), p.544-544, Article 544
• Main Authors: e Silva, Camila Rodrigues, Smoak, Joseph M., da Silva-Filho, Emmanoel Vieira
• Format: Article
• Language: English
• Subjects: Air quality; Air quality measurements; Air temperature; Alpha rays; Atmospheric pressure; Atmospheric Protection/Air Quality Control/Air Pollution; Correlation; Dry season; Earth and Environmental Science; Ecology; Ecotoxicology; Environment; Environmental Management; Environmental monitoring; Environmental science; Exposure; Geographical distribution; Geographical locations; Geology; Health risk assessment; Health risks; Indoor air pollution; International standards; Meteorological parameters; Mitigation; Monitoring/Environmental Analysis; Outdoor air quality; Public health; Radiation; Radon; Radon content; Radon in indoor air; Radon isotopes; Radon levels; Rainy season; Risk assessment; Rural areas; Seasonal variation; Seasonal variations; Seasons; Solar radiation; Statistical analysis; Statistical methods; Wet season; Wind speed
• ISSN: 0167-6369; 1573-2959
• DOI: 10.1007/s10661-020-08513-w

Poorly ventilated environments such as residences can accumulate radon gas to levels that are harmful to humans and thus produce a public health risk. To assess the risk from natural radiation due to indoor radon exposure, 222 Rn measurements, using an alpha RAD7 detector, were conducted in Timóteo, Minas Gerais state, southeastern Brazil. Indoor radon concentrations, along with meteorological parameters, were measured every 2 h during both wet and dry seasons in 2017 and 2018. The mean concentration of indoor radon varied between 18.0 and 412.8 Bq m −3 , which corresponded to an effective annual dose of 1.2 and 7.6 mSv y −1 . Average radon concentrations were significantly higher during the winter dry season, and there was a strong positive correlation with humidity in both wet and dry season. Furthermore, concentrations showed an inverse correlation with atmospheric pressure, wind speed, air temperature, and solar radiation. The radon levels are generally above the limits recommended by international standards, meaning that mitigation measures are needed to improve air quality to reduce human exposure and risk. Finally, through the statistical analysis, it was possible to determine the differences and similarities between the sampling points concerning the geology of the place and the geographical location.