The transfer of 239+240Pu, 241Am, 137Cs and 90Sr to the tissues of horses.

This research article investigates the levels of radioactive elements absorbed into the tissue of horses when fed on contaminated soil or a diet contaminated by a solution, providing necessary data to ensure the safety of consumers that rely on horse meat as a food source.

Significance of the Study

• The study provides important information about the transfer parameters of certain radioactive isotopes — specifically Plutonium-239 + Plutonium-240 (Pu), Americium-241 (Am), Cesium-137 (Cs), and Strontium-90 (Sr) — from the environment to horse tissue.
• It fills an information gap as horses, which are a primary food source in some countries, had lesser available data compared to other farm animals.
• The research helps improve the safety of populations that rely on horse meat, contributing to more accurate internal dose assessments.

Research Methodology

• Radioactive isotopes were introduced into the diet of young fillies, adult mares, and through the placental barrier into fetuses.
• These were fed with contaminated soil or a diet contaminated by a leachate solution for 60 days, after which the quantity of the transferred isotopes to the horse organs were quantified.

Findings

• The ingestion of soil by horses, especially for grazing ones at the Semipalatinsk Test Site, was found to transfer significantly lesser amounts of radioactive isotopes (up to three orders of magnitude lower) when compared to eating food contaminated by a leachate solution.
• The highest observed transfer factor for Am was 72 ± 22*10 d kg FW in the liver of a mare fed with leachate-contaminated feed.
• For Pu, the highest transfer factor was 31.8 ± 8*10 d kg FW, again found in the liver of a mare fed with leachate-contaminated feed.
• The highest transfer factor observed for Cs was 35.3*10 d kg FW in a filly fed with leachate-contaminated feed.
• The highest Sr transfer factor was found in the filly’s ribs, which was 720 ± 144 *10 d kg FW when fed a leachate-contaminated feed.

Conclusion and Further Research

• The findings from this study can help improve estimations of internal dosages due to the consumption of horse meat around the Semipalatinsk Test Site.
• However, the researchers do caution about the small sample size used in this study and recommend that future studies involve long-term monitoring and use a larger sample size for more accurate results.