Let us also keep in perspective the numbers. The numbers of villans to the numbers of victims. Also, equally important, the ability to be each type of villan versus the ability to be each type of victim.
In one case, guns, you have to be disturbed and have no future to be the villan, and becoming the victim is akin to winning a sick form of lottery.
In the other case, whether it is poisoning the envirornment via radiation or via any other form of pollution, the villians are still disturbed, but they actually do have the choice to do good and their situation is far from hopeless. Instead, they choose evil. And their victims, are their customers, and all the innocent bystanders that share the planet with their customers.
Who is more evil? Which villan should you be most afraid of?