nontoxic vs unsafe

nontoxic

adj

  • Not toxic; not poisonous. 

noun

  • A substance that is not toxic. 

unsafe

adj

  • Not safe (various senses); dangerous. 

verb

  • To remove the safety from (a weapon). 

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