On Sunday, a former Russian spy named Sergei Skripal and his daughter collapsed near a bench in Salisbury, England. “Her eyes were just completely white. They were wide-open but just white and [she was] frothing at the mouth,” a man who found the couple told CBS. “Then the man went stiff. His arms stopped moving, but he’s still looking dead straight.”
Classic signs of poisoning with a nerve agent.
British authorities later confirmed it was a nerve agent that sickened Skripal and his daughter, but they declined to name which one. The BBC reports it was not either of the two most infamous nerve agents: sarin, which was used in the 1995 Toyko subway attacks and most likely recently in Syria, or VX, which killed Kim Jong Un’s exiled half brother last year.
But all nerve agents work in similar ways. Molecularly, they are organophosphates. Physically, they are usually colorless liquids. And functionally, they all disable enzymes called acetylcholinesterase, which acts as an off switch in the nervous system.
“You can imagine that if you block one of the major ‘off-switches’ of the body, and are left with all the lights turned ‘on’ all of the time, the body might run into trouble,” a doctor told ABC Science.