I think the exclusion zone around Chernobyl proves that the bigger threat to other life from humans is not from pollution but from direct habitat destruction, competition for resources, and direct extermination.

The rate of species extinction might (though we can't be sure) go back to baseline rather quickly as soon as human pressure relaxed.

By laying out pros and cons we risk inducing people to join the debate, and losing control of a process that only we fully understand. - Alan Greenspan