What is the dart frog toxin allegedly used to kill Alexei Navalny?

Russian opposition leader Alexei Navalny was killed using a deadly toxin found in poison dart frogs in South America, the United Kingdom and some of its European allies said.

Traces of epibatidine were found in samples taken from Navalny’s body and most likely led to his death in a Siberian penal colony two years ago, the British Foreign Office said.

The allies said only the Russian state had the “means, motivation and opportunity” to deploy the deadly toxin.

The Kremlin called the discovery an “information campaign,” according to the Tass news agency.

What is the toxin?

Epibatidine is a naturally occurring neurotoxin isolated from the skin of the Ecuadorian poison dart frog, according to toxicology expert Jill Johnson.

It was “200 times more powerful” than morphine, she told the Russian BBC.

Epibatidine can be found naturally in dart frogs in the wild in South America and is manufactured in the laboratory.

Captive frogs do not produce this toxin and it is not found naturally in Russia, the European allies said in their press release.

The species known as Anthony’s poison arrow frog and phantom poison dart frog are among those that secrete the toxin on their skin.

Although epibatidine has been studied as an analgesic and to relieve painful inflammatory lung conditions, it 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 these nerve receptors, if dosed correctly, it can cause muscle twitching, paralysis, seizures, slowed heart rate, respiratory failure and ultimately death, she explained.

Alastair Hay, professor of environmental toxicology at the University of Leeds, told PA its effects can lead to blocked breathing and “anyone poisoned dies from suffocation”.

The toxin found in a person’s blood “suggests deliberate administration,” he added.

Epibatidine toxicity may even be “increased by co-administration of certain other drugs and these combinations have been researched,” Hay said.

How rare is the toxin?

Epibatidine is extremely rare and found in a single geographic region and only in trace amounts, Johnson said.

It is understood that the arrow frog mentioned by the British Foreign Office and others was Anthony’s poisonous arrow frog, a species endemic to Ecuador and Peru.

Frogs produce the chemical by eating the right foods to produce alkaloids – a type of organic compound – which make epibatidine and accumulate it in their skin. If the frog’s diet changes, its epibatidine stores will be depleted.

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

“This is an incredibly rare method of human poisoning. The only other cases of epibatidine poisoning that I know of were laboratory poisonings and non-fatal cases.”

What did Russia say?

European laboratories have confirmed that Navalny died from the obscure poison, the allies announced on Saturday.

Moscow has previously claimed that Navalny died of natural causes, although Navalny’s widow, Yulia Navalnaya, has always maintained that her husband was “murdered” by poisoning.

The Russian embassy in London denied any involvement by Moscow in Navalny’s death and called the announcement “the weakness of Western fabulists” and “necro-propaganda.”

Kremlin spokeswoman Maria Zakharova was quoted by Russia’s official Tass news agency as saying: “All talks and statements are an information campaign aimed at distracting attention from the pressing problems of the West.”

At the time of his death, Navalny had been in prison for three years and had recently been transferred to an Arctic penal colony.

According to Russian accounts, the 47-year-old man took a short walk, said he did not feel well, then collapsed and never regained consciousness.