The first human trial of a new drug that could reverse the effects of radiation from a dirty bomb or nuclear accident is taking place in the US.
HOPO 14-1 works against elements that can be used to make dirty bombs, which are explosive devices laced with radioactive substances.
Dirty bombs are different from nuclear ones as they can only contaminate an area of a few miles from the explosion, as opposed to a thousand.
Two drugs, both made with diethylenetriamine pentaacetate (DTPA), are already used on people exposed to radiation.
Iodine tablets have also been administered to people exposed to radioactive iodine from a nuclear accident, such as the one at Chernobyl in 1986.
But if proved to be safe and effective, HOPO 14-1 could be given to people in tablet form, which would be much easier than intravenous methods in the event of an emergency.
It would also offer an antidote to more dangerous elements than just iodine, including plutonium, americium and curium.
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The first phase of the trial is being funded by the US National Institute of Allergy and Infectious Diseases (NIAID) and conducted by the research institute SRI International in California.
It will be carried out on 42 healthy adults, aged 18 to 65, who will be given varying doses of the drug.
They will be monitored for 14 days, with results expected in 2024.
Weapons of mass disruption
Dirty bombs, also known as radiological devices or RDDs, are classed as “weapons of mass disruption” by US authorities.
They cause far less damage than nuclear bombs, or “weapons of mass destruction”. But if inhaled, ingested or exposed to an open wound, the substances they emit can cause cancer, DNA and organ damage.
No dirty bomb attacks have been successful.
Chechnya rebels planted a bomb containing dynamite and radioactive caesium-137 in Izmailovo Park in Moscow in 1996 but it was found and destroyed. Two years later, the Chechnyan intelligence service defused a dirty bomb left near a train line.
Al-Qaeda operatives have also been arrested for dirty bomb plots in the UK and US.
During its invasion of Ukraine, Russia has claimed that Ukrainian forces plan to dirty bomb its own citizens, but this has been dismissed as “transparently false” by the West.