Captain Planet and the Planeteers - Season 1 Episode 4

Verminous Skumm creates a substance that, when placed in water, will mutate its drinker into a rat-resembling character who willingly serves him. The Planeteers go to stop him, but Wheeler falls into a vat of it, and Linka and Gi are splashed, so the others must hurry to recover an endangered plant Ma-Ti's friend the Shaman believes may cure them. Meanwhile, Skumm plans to place the liquid in Ma-Ti's village water supply, then the Amazon to infect the country and perhaps even the world.