Exploring radon risk in groundwater: insights from few investigated areas in Morocco

Radon is present in most groundwater hosted by geological formations rich in uranium. It is a gas that dissolves easily in water, poses a potential health risk when present in water used in homes. For this purpose, an exploring study of radon concentration in groundwater was conducted in three selected areas in Morocco (the Anti-Atlas, the High Atlas and the Bahira areas) using RAD-7 detector. The radon contents measured in the 34 groundwater samples, range from 0.36 to 577.1 Bq L^− 1, with average of 52.99 Bq L^− 1. Among them, only three samples exceed the accepted limit of 100 Bq L^− 1, established by the world health organization and the European Commission. Considering the level recommended by U.S. environmental protection agency, 67.64% of the samples measured had concentrations greater than 11.1 Bq L^− 1. These results indicate significantly higher ²²²Rn concentrations in the groundwater of the Anti-Atlas compared to the High Atlas and occidental Meseta. This disparity could be attributed to the variation in lithology between these three different regions, as the granites are mainly the primary sources of radon in the region. The obtained annual effective doses show values ranging from 0 mSv y^− 1 to 2.10 mSv y^− 1 for the three regions, with samples in the Anti-Atlas and Bahira exceeding the safety limit of 0.1 mSv y^− 1 proposed by both the WHO and the European Commission. This exploring study is important for both the environment and human health since it can provide important information for radon-related regulations and programs.