Caesium-137 in the muscles of game animals in 2015-2022 – levels and time trend

Radioactive caesium-137 occurring in the environment may be taken up by plants and animals and pose a trophic threat to humans. Game animals living in forest ecosystems are very good bioindicators of the level of environmental contamination by ionising radiation. The main species measurably exposed to caesium-137 are the wild boar (Sus scrofa), the roe deer (Capreolus capreolus), and the red deer (Cervus elaphus). The study determined the levels of Cs-137 in muscle samples of these game animals in 2015–2022. Using gamma radiation spectrometry, 858 samples of game animal muscle tissue were examined: 508 wild boar, 145 roe deer and 205 red deer samples. Concentrations of Cs-137 varied widely (from minimum detectable activity (MDA) values to over 4,000 Bq/kg). In 63.4% of cases, the obtained concentrations exceeded the MDA. The permissible limit (600 Bq/kg for food) was exceeded in nine wild boar muscle samples, whereas it was not even exceeded once in roe or red deer muscle. The average concentration in wild boar was three times higher than in roe and red deer and amounted to 42.84 Bq/kg. The highest concentration of Cs-137 in wild boar muscle was 4,195 ± 372.0 Bq/kg, in roe deer muscle it was 111.5 ± 12.50 Bq/kg, and in red deer muscle was 86.70 ± 3.470 Bq/kg. The seven years’ data indicate that wild boar absorb the most caesium-137 among game animals. The concentrations of Cs-137 in the muscle of game animals in the years 2015-2022 were at a nearly constant level, a very slow diminution being noticeable over time in roe and red deer muscle.