Natural radioactivity analysis and radiological impact assessment from a coal power plant

Through combustion, a coal-fired power plant produces by-products, such as fly ash and bottom ash, which contain significant concentrations of radionuclides that cause environmental contamination, leading to health problems.

This study investigated the specific activity and radiological impacts of naturally occurring radioactive materials (NORMs) in the coal, fly ash, and bottom ash at a coal-fired power plant. Samples were collected from a coal-fired power plant in Malaysia.

Gamma spectrometry was used to determine the specific concentrations of NORMs, namely 40K, 232Th, 238U, in each sample. The radioactivity ranges for 238U, 232Th, and 40K in the soil were 22.7–150.7 Bq/kg, 20.7–153.6 Bq/kg, and 68.6–1594.4 Bq/kg, respectively. The coal, fly, and bottom ash samples contained 67.54–189.18 Bq/kg of 238U, 50.2–134.57 Bq/kg of 232Th, and 327.54–1114.40 Bq/kg of 40K. The radium equivalent activities (Raeq) in the samples were 164.55, 467.42, and 429.09 Bq/kg, respectively. Meanwhile, the absorbed dose rate (ADR) in the air ranged from 76.04 to 217.44 nGy/h. Internal and external hazards ranged from 0.44 to 1.26 and 0.63 to 1.77, respectively. The annual gonadal dose equivalent (AGDE) value fluctuated between 521.28 and 1,496.99 μSv.

The excess lifetime cancer risk (ELCR) oscillated from 1.30×10–3 to 3.75×10–3 indoors and 0.32×10–3 to 0.95×10–3 outdoors.