toxic waste vs waste material

toxic waste and waste material both are nouns.

Word	Noun	Adjective	Verb	Adverb
toxic waste	Yes	No	No	No
waste material	Yes	No	No	No

As nouns, waste material is a hypernym of toxic waste; that is, waste material is a word with a broader meaning than toxic waste:

toxic waste: poisonous waste materials; can cause injury (especially by chemical means)
waste material: any materials unused and rejected as worthless or unwanted

Other hypernyms of toxic waste include waste, waste matter, waste product.

toxic waste (noun)	waste material (noun)
poisonous waste materials; can cause injury (especially by chemical means)	any materials unused and rejected as worthless or unwanted