The concept of radiological sustainability has been reviewed using the possibility of the reutilization of NORMs regarding the 2050 sustainable development concepts. This study is reviewing the capability of re-production of NORM residues based on their properties and the applicable treatment before reutilization. Linking the waste producers and construction materials industry as mineral end-users could contribute to the creation of industrial symbiosis and result in waste reduction and preserving natural resources on one hand, and CO2 reducing and energy saving on the other hand. According to EU-BSS (European Basic Safety Standards Directive), the characterization of NORMs as a secondary raw material for use as construction materials is necessary, however as an additive or secondary material their radiological behavior and material properties are quite important regardless of their origin. This is to say that the reutilization of NORM residues provides a better financial and environmental solution while reducing possible radiological effects on humans. NORM residue or waste could become a high material resource for the cement industry. In this regard, the assessment of radium equivalents (Raeq) and external and internal indexes (I-indexes) are useful tools to classify NORM residues before their inclusion in building products. This assessment and/or indexes reflect the risk of external exposure much better than the specific activity concentration of Ra-226, Th-232 and K-40. Equally, building material properties such as density and thickness should be taken into consideration when designing building materials that contain NORM residue. Furthermore, mixtures or additives of NORM residues are proven to result in the reduction of activity concentration in the raw residue with other raw materials, and this offers flexible reuse options depending on the final product. By integrating radiological considerations into sustainable development initiatives, we can work towards a safer, healthier and more sustainable future.
In this study, a comprehensive investigation was conducted to determine the radioactivity levels of naturally occurring radioactive materials (NORMs) in heap pads/soil and water samples within and around the operational area of Tarkwa Gold Mine in Ghana. Gamma-ray spectrometry was used to determine the activity concentrations of 238U, 232Th, and 40K in heap pads/soil, and 226Ra, 228Th, and 40K in water samples. The average activity concentrations of 226Ra and 228Th in all water samples were below the World Health Organisation (WHO) recommended guidelines for drinking water. Similarly, the average activity concentrations of measured radionuclides in heap pads/soil samples taken from depths of 0–20 cm and 20–50 cm were found to be below the worldwide average reported values. The annual effective dose to the public was estimated to be around 0.16 mSv, which is below the recommended limit. The values of the hazard indices are also below the recommended limits, implying that if heap pads/soils are used for building purposes and construction, they will not pose any significant radiation hazard. The results of this study indicate that radiation levels are within the natural background radiation levels reported in the literature and are consistent with findings from similar studies conducted in Ghana.
Artisanal gold mining can enhance natural radioactivity in nearby environmental media. This study assessed health risks and environmental impacts associated with the release of natural radionuclides in Atiwa West, Ghana. Activities of naturally occurring radionuclides were measured in soil samples (Ra-226, Th-232, K-40) and water samples (Ra-226, Ra-228, K-40) by HPGe γ-spectrometry; Ra-226 in vegetation was estimated from soil activities using a transfer factor. The mean activity concentrations in soils were 22.1 ± 2.1 Bq/kg (Ra-226), 27.5 ± 2.3 Bq/kg (Th-232) and 198 ± 22 Bq/kg (K-40). At several water locations, Ra-226 and Ra-228 exceeded the WHO screening levels for drinking water of 1.0 Bq/L and 0.1 Bq/L, respectively. Radiological hazard indices attributable to inhalation and ingestion were evaluated. Overall, soil radiological risks were low; however, approximately 22% of sites recorded values above the global average annual gonadal dose equivalent (AGDE). In some locations, the committed effective dose from drinking water surpassed the WHO screening threshold of 0.1 mSv/y, with the associated excess lifetime cancer risk (ELCR) exceeding 2.9 × 10−4. Overall, the mining-affected waters presented a greater potential radiological impact than the soils, underscoring the need for water quality management and periodic monitoring in artisanal mining areas.