Armadillidium vulgare is a common species. But there are probably hundreds of species that share the same nickname because most people don't know the differences.
While isopods can sequester heavy metals within their bodies, this is a temporary solution. Upon their death and decomposition, the heavy metals are released back into the soil, so they do not permanently remove these contaminants from the environment.
I don't recommend anyone buy any of them, but one of the books (or possibly short stories? It's been a while) in the Ender series by OSC kind of touches on that.
They accumulate it in a specific organ, but they aren't magical alchemy machines. It stays in their bodies until they die, then they decompose and it goes back into the ground.
