Determination of tritium concentrations in humans before the development of a nuclear power plant in Turkey

Tritium contents in drinking and surface seawaters before the nuclear power plant planned in Sinop (Türkiye) and their radiological risks on human population

This study aims to determine the background levels of tritium radioisotope in drinking and seawater samples of Sinop province before the nuclear power plant was established in Sinop. In this context, a total of 174 water samples were collected, these are as follows: nine drinking water samples from the Sinop center and districts and 165 seawater samples from the seacoast from Samsun to Kastamonu. Tritium concentrations in the collected water samples were measured by the liquid scintillation counter. The minimum detectable activity for the method used was found to be 1.48 Bq/L. The tritium concentrations of the seawater and drinking water samples were found in the range of Collapse

Key Words Collapse

MESH Headings

• Adult
• Child
• Infant
• Humans
• Tritium
• Nuclear Power Plants
• Drinking Water
• Turkey

Collapse

Grants Collapse

Affiliation(s)

Serdar Dizman Department of Physics, Faculty of Arts and Sciences, Recep Tayyip Erdogan University, Rize 53100, Türkiye E-mail:
Feyza Zeynep Aşık Institute of Graduate Studies, Recep Tayyip Erdogan University, Rize 53100, Türkiye
Ali Erdem Özçelik Department of Landscape and Architecture (Geomatics Engineer), Faculty of Engineering and Architecture, Recep Tayyip Erdogan University, Rize 53100, Türkiye
Recep Keser Department of Basic Sciences, Faculty of Engineering, Samsun University, Samsun 55100, Türkiye
Filiz Korkmaz Görür Department of Physics, Faculty of Arts and Science, Bolu Abant İzzet Baysal University, Bolu 14100, Türkiye

Collapse

Tritium concentrations and consequent doses in bottled natural and mineral waters sold in Turkey and Azerbaijan

In this study, tritium levels in commercially sold bottled natural and mineral waters in Turkey and Azerbaijan were determined. Tritium measurements were performed using Liquid Scintillation Counter (PerkinElmer TriCarb 2910 TR). 16 natural and 11 mineral samples from Turkey and 7 natural and 8 mineral samples from Azerbaijan, for a total of 42 commercially sold water samples were analyzed. The Minimum Detectable Activity (MDA) value for the method used was found as 1.69 Bq L^-1. In total, 7 of the natural water samples and 8 of the mineral water samples were found to be below the MDA value. The average activity concentrations in natural and mineral water samples were found as 2.23 ± 0.90 Bq L^-1 and 2.51 ± 0.90 Bq L^-1 for Turkey and 2.69 ± 0.91 Bq L^-1 and 2.43 ± 0.89 Bq L^-1 for Azerbaijan, respectively. In addition, annual effective dose rates and lifetime cancer risk values for the water samples were calculated. These radiological parameters were compared with the values recommended by international organizations. The results demonstrated that consumption by humans of the studied waters would not constitute any health risks in terms of tritium.

Tritium in urine from members of the general public and occupationally exposed workers in Lund, Sweden, prior to operation of the European Spallation Source

A powerful neutron source, the European Spallation Source (ESS), is currently under construction in Lund, Sweden (~90 000 inhabitants). Levels of tritium (³H) in urine were estimated in members of the public in Lund and employees at the ESS using liquid scintillation counting, to obtain baseline levels before the start of operation of the ESS. These were compared with levels in other occupationally exposed radiation workers. Both the spallation reaction in the ESS tungsten target and the activation of various materials by the protons produced by the 5 MW linear accelerator will generate tritium, which will be released into the atmosphere mainly as tritiated water (HTO). Urinary HTO activity concentrations were determined in a total of 55 individuals belonging to four different categories: ESS employees, neighbours of the ESS, members of the general public in Lund and exposed workers from other facilities. The participants were asked to provide information on their beverage intake the day before urine sampling. The urine samples were filtered on activated charcoal and distilled before analysis. The effect of sample preparation on the isotope fractionation of urine samples was investigated by isotope ratio mass spectrometry (IRMS) of ²H/¹H, which showed no influence. IRMS was also used to investigate if the ratio between the stable hydrogen isotopes (²H/¹H) could provide useful data of the origin, and hence the tritium concentration, of various types of drinking water. Urinary HTO activity concentrations determined using liquid scintillation counting (LSC) were found to be below the minimum detectable activity (MDA) of 2.1 Bq⋅L^-1 for most of the participants. Five of the workers actively handling organic tritiated material were found to have activity concentrations between 3.5 and 11 Bq⋅L^-1, which were higher than the average value in local tap water of 1.5 ± 0.6 Bq⋅L^-1. The results will be used to evaluate the radiological impact on the population from future releases of tritium resulting from the operation of the ESS.

Tritium internal dose estimation from measurements with liquid scintillators

Tritium may exist in several chemical and physical forms in workplaces, common occurrences are in vapor or liquid form (as tritiated water) and in organic form (e.g. thymidine) which can get into the body by inhalation or by ingestion. For internal dose assessment it is usually assumed that urine samples for tritium analysis are obtained after the tritium concentration inside the body has reached equilibrium following intake. Comparison was carried out for two types of vials, two efficiency calculation methods and two available liquid scintillation devices to highlight the errors of the measurements. The results were used for dose estimation with MONDAL-3 software. It has been shown that concerning the accuracy of the final internal dose assessment, the uncertainties of the assumptions used in the dose assessment (for example the date and route of intake, the physical and chemical form) can be more influential than the errors of the measured data. Therefore, the improvement of the experimental accuracy alone is not the proper way to improve the accuracy of the internal dose estimation.