In 2007, a man from Woodbridge, Virginia was rushed into hospital after inhaling an aerosolised version of one of the deadliest poisons on the planet. He was not the victim of a terrorist attack. He wasn’t working in a biohazard laboratory. He was trying to clean out his fish tank.

The man, who posts on the Reef Central Forums as Steveoutlaw, was trying to get rid of a colony of zoanthids – a relative of corals and sea anemones – that was infesting his aquarium rocks. He had heard that boiling water would do the trick. When he tried it, he accidentally inhaled some of the steam.

Twenty minutes later, his nose was running and he had a cough. Four