A comparison of different detection techniques for ¹³⁷Cs measurements of cattle in vivo.

The article focuses on developing and validating a rapid, reliable method for measuring radioactive cesium-137 (^137Cs) contamination in living cattle and wild boars to ensure food safety and compliance with regulatory limits following nuclear or radiation accidents. Various portable radiation detectors—including NaI(Tl), cerium bromide (CeBr_3), gadolinium aluminum gallium garnet (GAGG), and cadmium zinc telluride (CZT)—were calibrated using volumetric ^137Cs sources and tested in situ, supported by Monte Carlo simulations with a newly created mathematical cow phantom. Field measurements in Belarus demonstrated good agreement between in vivo detector readings (using the TIM 601 spectrometer with a NaI(Tl) crystal) and laboratory analyses of meat samples, while tests on wild boars in Czechia highlighted the need for calibration adjustments due to morphological differences. Among the detectors, CeBr_3 showed the lowest minimum detectable activity and best energy resolution for rapid on-site screening, whereas CZT was less suitable due to lower detection efficiency. The proposed methodology is intended for use by official monitoring bodies and meat producers to screen livestock contamination efficiently and support safe agricultural practices in contaminated regions.