What is dart frog toxin, the poison linked to Alexei Navalny’s death?

The toxin is reportedly 100 times more powerful than morphine

Epibatidine, the highly potent toxin Britain has linked to the death of Alexei Navalny, is reportedly 100 times more powerful than morphine.

This extremely toxic, nicotine-like compound originates from the Epipedobates genus of poison dart frogs, found exclusively in northern South America. Crucially, these amphibians are not indigenous to Russia.

Species such as the brightly coloured Anthony’s poison arrow frog and the Phantasmal poison frog secrete this substance onto their skin. Researchers theorise that the frogs acquire the toxin through their diet, as captive-bred animals lack it, and wild populations exhibit varying levels depending on their habitat.

Yulia Navalnaya, human rights activist and wife of Alexei Navalny, gives a press statement on the death and circumstances of her husband's death. (Kay Nietfeld/dpa via APAP)

Epibatidine has been investigated as a pain killer and for relief from painful inflammatory conditions of the lung such as asthma and pulmonary fibrosis.

However, it is about a hundred times more potent than morphine and because of its toxicity is not used clinically.

Professor Alastair Hay said Epibatidine acts to inhibit nerve action by blocking nicotinic receptors in the central and peripheral nervous systems.

The Professor (Emeritus) of Environmental Toxicology at the University of Leeds added: “The effect of blocking these receptors is muscle paralysis and paralysis of the respiratory system.

“So, breathing is blocked, and any person poisoned dies from suffocation.”

Professor Hay said the presence of the toxin in a person’s blood “suggests deliberate administration”.

He added: “Epibatidine toxicity can even be increased by co-administration of certain other drugs and these combinations have been researched.

“If epibatidine, a toxin, was indeed used to poison Alexei Navalny, this is in violation of the 1972 Biological and Toxin Weapons Convention (BTWC) and the 1993 Chemical Weapons Convention (CWC).

“The Soviet Union was a co-sponsor of the BTWC. Russia is a signatory of both the BTWC and CWC.

“If Russia used Epibatidine to poison Mr Navalny it has violated two treaties it has sworn to uphold.”

Epibatidine can be detected using a combination of gas chromatography and mass spectrometry.

Gas chromatography helps separate out compounds of interest and mass spectrometry breaks up chemicals into particular fragments to create a unique fingerprint of the substance which can then be identified.