Definitely.
I'd love engines and dirty generators, maybe some machines too, to produce pollution. If pollution got high enough animals and trees would die out, and rain would become acidic, damaging the player. Really high pollution would cause a smoggy mess that would reduce the player to 7 hearts whilst in it.
Radiation should also occur, when a reactor blows up it irradiates several chunks around itself, players in these chunks without hazmat gear rapidly die, and mobs are mutated into twisted monstrosities.