South Africa has begun utilizing an innovative initiative by the International Atomic Energy Agency (IAEA) that applies radiation to combat poaching and illegal wildlife trade. As part of the project, volunteers and nuclear experts treat rhino horns with radiation, complicating their export from the country, according to an IAEA press release.
The project is named Rhisotope—a combination of "rhino" and "isotope" in English. Within its framework, specialists introduce safe isotopes of radioactive materials into the animals' horns, which scientists can monitor using a specialized system. In the event of a smuggling attempt, South African security services connected to the IAEA's radiation monitoring system will detect the radioactive emissions and can confiscate the rhino horns.
Launched in 2021, the Rhisotope project underwent four years of safety research at the IAEA and South Africa's University of the Witwatersrand, yielding no negative impact on rhinos from the isotopes used. During the pilot phase in Limpopo province, isotopes were implemented in 20 rhinos in local national parks. Monitoring conducted by a European university confirmed the safety of radiation treatment and its effectiveness in combating smuggling and poaching.
"Project Rhisotope illustrates how nuclear science and nuclear security infrastructure can be repurposed to address global challenges. The IAEA assists countries in maximizing the benefits of nuclear energy. By repurposing existing nuclear security infrastructure, we can aid in protecting one of the world's most iconic and endangered species," stated IAEA Director General Rafael Grossi.
Following its implementation in South Africa, the agency plans to expand Rhisotope to other regions inhabited by rhinos and hopes to explore applications of radiation for the preservation of other animal species across Africa.
In 2024, the number of rhinos killed by poachers in South Africa decreased by 16%. The past year saw 79 fewer rhinos killed than in 2023. In June 2025, researchers reported that horn removal contributed to an 80% reduction in poaching rates in South Africa.
