What Are the Poison Dart Frogs Allegedly Used to Kill Alexei Navalny?

Russian opposition leader Alexei Navalny was killed using a lethal poison found in South American dart frogs, according to the UK government and a number of European countries.

Traces of epibatidine were found in Navalny’s body and most likely caused his death in a Siberian prison two years ago, the UK Foreign Office said.

A number of Britain’s allies said only the Russian state had the “means, motive, and opportunity” to use this lethal poison.

The Kremlin dismissed the findings as an “information campaign”, according to the Tass news agency.

What kind of lethal poison is it?

Epibatidine is a naturally occurring neurotoxin from the skin of Ecuador’s poison dart frogs, according to toxicology expert Jill Johnson.

She told BBC Russia that the poison is “200 times more potent” than morphine.

Epibatidine can be found naturally in dart frogs in the wild in South America and can also be produced in laboratories.

Poison dart frogs kept in captivity do not produce this toxin, and it is not found naturally in Russia, said the UK’s European allies.

Species known as Anthony’s poison dart frog and the Phantasmal poison frog are among those that secrete the toxin onto their skin.

Although epibatidine has been researched as a painkiller and used to alleviate painful inflammatory lung conditions, the substance is not used clinically due to its toxicity.

How does dart frog poison work?

This powerful chemical compound acts on nicotinic receptors in the nervous system, according to Johnson.

Because it overstimulates nerve receptors, if administered at the right dose it can cause muscle twitching, paralysis, seizures, slow heart rate, respiratory failure, and ultimately death, she explained.

Alastair Hay, professor of environmental toxicology at the University of Leeds, told the PA news agency that its effects can cause obstructed breathing, and that “everyone who is poisoned dies from asphyxiation”.

The discovery of the poison in a person’s blood “indicates deliberate administration”, he added.

The toxicity of epibatidine can even “be enhanced by concurrent administration of certain other drugs, and this combination has been researched”, Hay said.

How rare is this poison?

Epibatidine is extremely rare and is found in only one geographical region and only in very small quantities, Johnson said.

The dart frogs referred to by the UK Foreign Office and a number of European countries are Anthony’s poison dart frogs, a species endemic to Ecuador and Peru.

These frogs produce toxic chemicals through their diet, consuming the right food to produce alkaloids — a type of organic compound that creates epibatidine — and accumulate it in their skin. If the frogs’ diet changes, their epibatidine reserves become depleted.

“Finding a wild frog in the right place, eating the right food to produce the right alkaloids, is nearly impossible,” Johnson said.

“This is an extremely rare method of human poisoning. The only other case of epibatidine poisoning I am aware of was laboratory-based and non-fatal.”

What is Russia’s response?

European laboratories confirmed that Navalny died from an obscure poison, the UK government and its allies said on Saturday.

Moscow had previously claimed that Navalny died of natural causes. However, Navalny’s widow, Yulia Navalnaya, has consistently maintained that her husband was “killed” with poison.

The Russian Embassy in London denied Moscow’s involvement in Navalny’s death and described the announcement as “the feeble-mindedness of Western storytellers” and “death propaganda”.

Kremlin spokesperson Maria Zakharova was quoted by the Russian state news agency Tass as saying: “All the talk and statements are an information campaign aimed at diverting attention from the West’s pressing problems.”

At the time of his death, Navalny had been imprisoned for three years and was subsequently transferred to a Siberian prison colony.

According to official Russian reports, the 47-year-old went for a brief walk, said he felt unwell, then collapsed and never regained consciousness.