Indoor Radon in public schools, a preliminary study in Central Portugal

Good air quality is considered to be a basic condition for human health and well-being. Exposure to air contamination is undoubtedly associated with diverse adverse health effects, particularly in vulnerable population subgroups such as children. Regions with natural Radon gas (Rn) emissions are of major concern worldwide, due to the negative impacts on Air Quality. Being colorless and odorless, Rn cannot be detected by humans. Natural/geogenic Rn contribution to indoor air is considered a leading cause of lung tumors by the World Health Organization. Portugal implemented the 2013/59/Euratom directive in 2018, establishing ionizing radiation guidelines with an indoor air Rn maximum of 300 Bq/m³.

Guarda district (Portugal) is known for the natural geogenic Rn emissions and its impact on indoor Air Quality. A preliminary indoor Rn gas monitoring study was undertaken in 2019 (3 months period, March to May) in all the public schools (nursery to high school) of of Guarda city. A mean concentration of 1145 Bq/m³ was monitored, with a maximum value of 3604 Bq/m³ in a nursery school. From the twenty schools monitored, only five schools presented indoor Rn concentration bellow the Portuguese legislation and none bellow the WHO guideline of 100 Bq/m³. These results displayed an urgent and mandatory need for advanced and intensive air monitoring campaigns and assessment of implications on human health, especially in children during school hours, where they can stay up to 10 h/day.