Rollie Pollies (pillbugs, isopods, wood lice) remove heavy metals from soil

Rollie Pollies (aka rolly polly, wood lice, isopod) have this name because they are little bugs that roll up in a ball if they feel threatened. But they are not bugs at all, they are crustaceans with 7 pairs of legs. They eat dead, decaying matter and help break down stuff in the garden soil. Pill bugs like cool, shady locations, like worms, and are often found under another object, like a piece of wood or rain barrel.

Pill bugs can take in heavy metals like copper, lead, zinc, cadmium, and these crystallize in their gut.

Source
Natural News. Mar 20, 2015.