Chenium

Chenium was a highly toxic and corrosive chemical. It was a byproduct from the manufacture of Qualon 37.

In 2050, Inspector Drake's attempts to replicate Medes technology produced chenium which leaked into the River Thames, polluting it. When Starkey and K9 discovered fish which had died from the pollution, they took one to Gryffen Manor and analysed it, discovering the presence of chenium. K9 (who was damaged due to chenium exposure), Jorjie and Darius traced the source of the pollution, but it was June Turner who put a stop to the experiments. After she freed the Medes, they cleaned up the pollution before leaving in their spaceship. (K9TV: Alien Avatar)