Evaluation of radiological hazards and annual effective dose from radon and toxic elements in groundwater of Sulaymaniyah governorate, Iraq

The study evaluates radiological risk and potential toxic element (PTE) contamination in 69 groundwater samples in the Sulaymaniyah Governorate, Iraq. Focused on single pollutants, this research activates a hazard assessment framework. Radon ( 222 Rn) concentration was determined using radon detectors (RAD-7), while hazardous substances were measured using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The temperatures ranged from 16.9 °C to 33 °C, and the well depth ranged from 18 to 172 m. Radon concentration ranged from 0.95 ± 0.13 Bq L − 1 in sample W44 to 20.1 ± 1.43 Bq L − 1 for sample W63, with an average of 4.56 ± 0.89 Bq L − 1 . Notably, sample W63 exceeded the Environmental Protection Agency (EPA) guideline, at 11.1 Bq L − 1 . The estimated annual effective dose recorded for a member of the public at 152.00 μ Sv y − 1 . This level surpasses the World Health Organization (WHO) limit at 100 μ Sv y − 1 . In addition, the maximum probability of excess lifetime cancer risk (ELCR) due to inhalation of Radon was 5.32 × 10 − 4 per 10,000 persons, which is five times above the international standard level. While most PTE levels remained below the WHO limit standards. Based on the study findings, the elevated radon concentration indicates the need for urgent intervention. This study is the first conducted in the region and provides a comprehensive assessment and serves as an essential baseline for the application of aeration and reverse osmosis treatment technologies.