What is the ‘dart frog’ toxin, said to be linked to Alexey Navalny’s death?

EXPLAINERThe UK, France, Germany, Sweden and the Netherlands allege that Russia poisoned Navalny, which caused his death about two years ago.Published On 15 Feb 2026Five European countries – the United Kingdom, France, Germany, Sweden and the Netherlands – have accused Russia of using a toxin from poison dart frogs to kill Kremlin critic Alexey Navalny.The European allies claimed on Saturday that Navalny was poisoned while he was held in an Arctic penal colony two years ago, a claim Moscow rejected as propaganda.Recommended Stories list of 4 itemslist 1 of 4Russia bans Human Rights Watch in widening crackdown on criticslist 2 of 4Exiled Russian accused of spying on opposition, including Navalny movementlist 3 of 4Global system of human rights in ‘peril’, warns HRW in its annual reportlist 4 of 4Russia’s Alexey Navalny killed by dart frog poison, European nations allegeend of listNavalny died, aged 47, in an Arctic prison colony in February 2024, after being convicted of extremism and other charges, all of which he denied. Russian authorities said the politician became ill after a walk and died from natural causes.What did the European countries say about Navalny’s poisoning?In a joint statement, the five countries said analyses of samples from Navalny’s body “conclusively” confirmed the presence of epibatidine, a toxin found in poison dart frogs in South America and not found naturally in Russia.The UK said on Saturday the poisoning demonstrated “an alarming pattern of behaviour”.It held a public inquiry into the poisoning in the UK of Russian double agent Sergei Skripal in 2018. It concluded last year that Russian President Vladimir Putin must have ordered the Novichok nerve agent attack.“Russia claimed that Navalny died of natural causes. But given the toxicity of epibatidine and reported symptoms, poisoning was highly likely the cause of his death,” the joint statement said.The joint statement added that the latest findings underlined the need for Russia to be held accountable for “its repeated violations of the Chemical Weapons Convention and, in this instance, the Biological and Toxin Weapons Convention”.It is unclear how the European allies obtained samples from Navalny’s body.What are poison dart frogs?The statement said analysis of samples from Navalny’s body confirmed the presence of epibatidine.Epibatidine is a neurotoxin secreted by dart frogs in the wild in South America. These small and brightly coloured frogs are typically found in rainforests.It can also be manufactured in a lab, which European scientists suspect was the case with the substance used on Navalny. It works on the body in a similar way to nerve agents, causing shortness of breath, convulsions, seizures, a slowed heart rate and ultimately death.How did Russia respond?The Russian government, which has repeatedly denied any responsibility for Navalny’s death, dismissed the latest allegations as “a Western propaganda hoax”, according to the state news agency TASS, while the Russian embassy in London said: “One must ask what kind of person would believe this nonsense about a frog.”“When the test results are available and the formulas for the substances are disclosed, we will comment accordingly,” Russian Foreign Ministry spokesperson Maria Zakharova was quoted as saying by the agency.“Until then, all such assertions are merely propaganda aimed at diverting attention from pressing Western issues,” TASS quoted her as saying. The report also said she described Navalny as a blogger “officially designated as a terrorist and extremist in Russia”.Who was Alexey Navalny and when did he die?Navalny was a Russian opposition leader.In 2008, he became notorious by alleging corruption in state-run corporations, such as gas giant Gazprom and oil behemoth Rosneft, through his blogs and other posts.Two years later, he founded RosPil, an anticorruption project run by a team of lawyers that analyses spending of state agencies and companies, exposing violations and contesting them in court. In 2011, he established the Foundation for Fighting Corruption, which became his team’s main platform for exposing alleged corruption among Russia’s top political ranks.Navalny was the target of an earlier poisoning in 2020, with a nerve agent in an attack he blamed on the Kremlin, which always denied involvement. His family and allies fought to have him flown to Germany for treatment and recovery.Five months later, he returned to Russia, where he was immediately arrested and imprisoned for the last three years of his life. He died on February 16, 2024.His death was announced minutes before the opening of the Munich Security Conference in 2024. In response, the conference made a rare schedule adjustment to allow his widow, Yulia Navalnaya, to address the conference, and she called for Putin to be held accountable.“I was certain from the first day that my husband had been poisoned, but now there is proof … I am grateful to the European states for the meticulous work they carried out over two years and for uncovering the truth,” she said on social media while attending this year’s Munich conference on Saturday.Navalny was born in 1976 in the western part of the Moscow region. He graduated from Russia’s RUDN University, where he majored in law. He also earned a degree in economics in 2001 while working as a lawyer.