JOHANNESBURG • Researchers are working on a pilot programme backed by Russia's Rosatom Corp to inject rhino horns with radioactive material to discourage consumption and make it easier to detect illegal trade.

Poachers killed 394 rhinos in South Africa for their horns last year, government data shows, with public and private game reserves lacking the resources to protect the animals that live there.

While the toll was a third lower than in 2019 and the sixth straight drop, illegal hunting remains the biggest threat to about 20,000 of the animals in the country - the world's biggest rhino population.

Thousands of existing sensors along international borders could be used to detect radioactive material inserted into the horns, according to Professor James Larkin from the University of Witwatersrand in Johannesburg, who has a background in radiation protection and nuclear security.

"A whole new army of people" would then be able to detect the illegal movement of rhino horns, he said.

Some alternate methods of discouraging poaching, including poisoning, dyeing and removing the horns, have raised debate over their virtue and efficacy.

The Rhisotope Project, the new anti-poaching initiative, started this month with the injection of an amino acid into two rhinos' horns to detect whether the compound will move into the animals' bodies. Additional studies using computer modelling and a replica rhino head will also be done to determine a safe dose of radioactive material.

Rhino horn is used in traditional medicine as it is believed to cure ailments such as cancer.

"If we make it radioactive, there will be a reticence by these people to buy it," said Prof Larkin.

If the method is proven to work, it could also be used to curb illegal trade in elephant ivory.