Radiological health risk maps of drinking water in Diyarbakır city, Türkiye

Quantifying Radon-222 (²²²Rn), gross alpha (α) and beta (β) emitting radionuclides in drinking water is crucial for assessing water quality and potential long-term impacts on human health. Therefore, the aim of this study is to investigate the radiological characteristics and the spatial distribution of drinking water samples from Diyarbakır province, Türkiye using the geostatistical approach. The measurements of ²²²Rn and gross α/β were scrutinized using a radon gas analyzer (AlphaGUARD PQ 2000 PRO) and a gas proportionate α/β counter (Berthold, LB 770 model). Spatial distribution maps were generated through the Ordinary Kriging method to visualize these parameters. The values of ²²²Rn, gross α and β activity in drinking water were established to be in the range of 258-1393 mBq L^-1, 12-243 mBq L^-1 and 32-380 mBq L^-1, respectively. The associated averages of the total annual effective dose (AEDt_otal) and total lifetime cancer risk (LCR_total), of drinking water were estimated to be 59.56 μSv y^-1 and 2.57E - 04, respectively. Although the average LCR_total was below the WHO threshold (3.85E - 04), it remained above the United States Environmental Protection Agency (US EPA) limit (1E - 04). These outcomes highlight the need for ongoing monitoring and further investigation of local water supplies to safeguard public health.