nontoxic vs nonpoisonous

nontoxic and nonpoisonous both are adjectives.

Word	Noun	Adjective	Verb	Adverb
nontoxic	No	Yes	No	No
nonpoisonous	No	Yes	No	No

As adjectives, nontoxic and nonpoisonous are synonyms defined as:

Other synonyms of nontoxic include non-poisonous.

nontoxic (adjective)	nonpoisonous (adjective)
not producing or resulting from poison	safe to eat
safe to eat	not producing poison