pollute vs purify

pollute

verb
  • To violate sexually; to debauch; to dishonour. 

  • To make something harmful, especially by the addition of some unwanted product. 

  • To make something or somewhere less suitable for some activity, especially by the introduction of some unnatural factor. 

  • To corrupt or profane 

adj
  • Polluted; defiled. 

purify

verb
  • To free from guilt or sin. 

  • To cleanse, or rid of impurities. 

  • To become pure. 

How often have the words pollute and purify occurred in a corpus of books? (source: Google Ngram Viewer )