Optimization of a new liquid scintillation spectrometer for the measurement of environmental levels of 3H in water samples

• Published in: Journal of environmental radioactivity 2024-07, Vol.277, p.107465, Article 107465
• Main Authors: García-León, J.L., García-León, M., Manjón, G., Rivera-Silva, J.
• Format: Article
• Language: English
• Subjects: humans; liquids; radioactivity; spectrometers
• ISSN: 0265-931X; 1879-1700; 1879-1700
• DOI: 10.1016/j.jenvrad.2024.107465

The activity concentration of 3H in water samples collected from places unaffected by nuclear activities or for human consumption can be very low. In these cases, determination procedures must achieve a Minimum Detectable Activity (MDA) low enough to ensure that 3H is accurately determined. In this paper, we present a method that uses a new Liquid Scintillation Spectrometer (LSC in what follows): the Quantulus GCT 6220. Furthermore, a new liquid scintillation cocktail, the ProSafe LT+, has been tested for 3H measurement, showing to be a good option for the determination of low levels of this radionuclide. The MDAs achieved are low enough to enable the measurement of very low levels of 3H in recent environmental water. The results obtained using a Quantulus GCT 6220 and Prosafe LT + are compared to those obtained with a Quantulus 1220 and Prosafe HC + as liquid scintillation cocktail. •3H in tap water in the city of Seville is determined routinely.•3H in tap water in Seville has been steadily decreasing for the last few years.•The liquid scintillation cocktail LT + leads to low MDAs for 3H determination.•The Quantulus GCT 6220 can be a competitive option for the determination of low 3H activities.•The new scintillation cocktail and spectrometer have been validated with the determination of a Quality Control sample.