AMINO ACID PROFILE OF HORSEMEAT IN PARASCARIDOSIS: A COMPARISON OF AREAS WITH DIFFERENT RADIATION-RISK LEVELS NEAR THE FORMER SEMIPALATINSK NUCLEAR TEST SITE

Abstract

In pasture-based horse production near the former Semipalatinsk Nuclear Test Site, product assessment should account for both local radioecological conditions and the parasitological status of animals. This study examined territorial variation in the amino acid profile of meat from horses infected with Parascaris equorum across four radiation-risk categories and descriptively compared the findings with radiometric characteristics of the farms. Samples were collected in 2024-2025 from farms in Bodene, Beskaragai, Sagyr, and Zhantikey. Gamma exposure dose rate, beta-particle flux density, and equilibrium-equivalent volumetric radon activity were used to characterize the radiation environment. Amino acids were quantified by liquid chromatography on a Shimadzu LC-20 Prominence system in meat from 40 horses with parascaridosis. Territorial groups were compared descriptively by calculating absolute and percentage deviations from the selected comparison level. Recorded values ranged from 0.10 to 0.32 µSv/h for gamma exposure dose rate, from 4.1 to 8.6 particles/(min·cm²) for beta-particle flux density, and from 66 to 128 Bq/m³ for indoor radon activity. Total essential amino acids amounted to 7,486 mg/100 g in Bodene, 7,682 mg/100 g in Beskaragai, 7,881 mg/100 g in Sagyr, and 8,081 mg/100 g in Zhantikey. The respective deficits were 8.60, 6.20, 3.77, and 1.33%, with tryptophan and methionine showing the largest differences. The deficit for the total amino acid pool declined from 8.75% in the extreme-risk area to 2.43% in the minimum-risk area. This spatial association should not be interpreted causally because an uninfected control group was unavailable to separate radiation-related and parasitological effects.