South African scientists have launched an anti-poaching campaign in which rhino’s horns will be injected with a radioactive material.

The group, from the University of the Witwatersrand, said the process is harmless to rhinos but will allow customs officers to detect smuggled horns as they’re transported across the world.

South Africa has the largest rhino population in the world, and hundreds of the animals are poached there every year.

The university’s venture, called the Rhisotope Project, was launched on Friday after six years of research and testing.

“Our goal is to deploy the Rhisotope technology at scale to help protect one of Africa’s most iconic and threatened species,” said Jessica Babich, head of the Rhisotope Project.

“By doing so, we safeguard not just rhinos but a vital part of our natural heritage.”

Tests conducted in the pilot study, which involved 20 rhinos, confirmed that the radioactive material was not harmful to the animals.

“We have demonstrated, beyond scientific doubt, that the process is completely safe for the animal and effective in making the horn detectable through international customs nuclear security systems,” said James Larkin a professor at Wits University who is also part of the project.

The horns of African rhinos are often exported to Asian markets were they are used in traditional medicine and also seen as a status symbol.

White rhinos are considered threatened, while black rhinos are critically endangered.