Uranium and thorium levels in urine and hair of coal miners and local residents in Shanxi, China

Uranium and thorium are naturally occurring radionuclides that may pose health risks when released into the environment through coal mining activities. This study aimed to investigate the levels of uranium and thorium exposure among coal miners and nearby residents in Shanxi, China. Urine and hair samples were collected from 51 participants, including 30 coal miners and 21 nearby residents. The concentrations of uranium and thorium were measured using inductively coupled plasma mass spectrometer. Subgroup analysis was performed to investigate the effects of environmental and occupational factors. Both urine and hair samples showed uranium and thorium concentrations higher than typical baseline values, indicating environmental and occupational exposure. Uranium levels in urine were notably higher in coal miners, especially among those with shorter work duration, suggesting recent or ongoing exposure. Thorium concentrations displayed limited variability and did not significantly differ between miners and residents. Uranium exposure appears to be closely linked to mining operations and environmental contamination in the region, whereas thorium exposure remains relatively uniform across groups. These findings underscore the need for further investigation into the long-term health effects of uranium and thorium exposure in coal mining areas and call for targeted interventions to reduce exposure risks.