fumigate vs oxygenate

fumigate

verb
  • To disinfect, purify, or rid of vermin with the fumes of certain chemicals. 

oxygenate

verb
  • To treat or infuse with oxygen 

  • To give (a patient) oxygen therapy. 

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