RADIOECOLOGICAL ASSESSMENT OF ENVIRONMENTAL COMPONENTS AND GOAT MILK IN THE IMPACT ZONE OF THE FORMER SEMIPALATINSK TEST SITE

Abstract

This study presents a comprehensive radioecological assessment of environmental components and goat milk produced in areas with varying levels of radiation risk within the former Semipalatinsk Nuclear Test Site. The research was conducted in four settlements of the Abai Region (Dolon, Karaul, Borodulikha, and Kokpekty), representing zones of extreme, maximum, high, and minimal radiation hazard. Samples of soil, plants, water, and goat milk were collected and analyzed for the content of key radionuclides (¹³⁷Cs, ⁴⁰K, and ¹³¹I) using gamma-spectrometric methods. In addition, organoleptic and physicochemical properties of goat milk were evaluated in accordance with regulatory standards. The results revealed a clear gradient in radionuclide concentrations across the studied areas, with the highest levels detected in the zones of extreme and maximum radiation risk. The transfer of radionuclides along the trophic chain “soil–plant–animal–milk” was confirmed, demonstrating the influence of residual environmental contamination on agricultural products. Despite the observed differences in radionuclide content, all milk samples met established safety standards, and the activity concentrations remained well below permissible limits. No significant negative effects of radiation on the organoleptic or physicochemical characteristics of goat milk were identified. The findings indicate the stability of milk quality under conditions of chronic low-level radiation exposure and confirm the absence of a significant radiological risk for consumers. The study expands current knowledge on radionuclide migration in agroecosystems of the former test site and highlights the importance of continuous environmental monitoring to ensure food safety and sustainable agricultural development in affected regions.