Definition of "unpollute"

Suppose the President were to say (copying some language used once before) that, before the end of this decade, we shall unpollute the Great Lakes.

1970, Monograph - Issues 11-14, page 85

And it is now time for the industry to fully realize that it cannot escape its responsibility to unpollute the American drinking environment, just as other industries have found that they cannot escape their responsibility to unpollute the natural environment.

1975, Morris E. Chafetz, Research, Treatment, and Prevention

If he wants to unpollute something, let him unpollute the movies. All them nudies.

1979, Richard Adler, All in the family: a critical appraisal, page 80

How can we throw off the mantle of ethical invisibility and, at the same time, unpollute the atmosphere and the environment, and, as one black poet wrote, "clean out the world for virtue and love"?

1992, Richard Kenneth Barksdale, Praisesong of Survival: Lectures and Essays, 1957-89, page 51

Let your departure unpollute our city.

2010, Publius Papinius Statius, The Thebaid: Seven against Thebes