lead poisoning vs unwellness

lead poisoning and unwellness both are nouns.

Word	Noun	Adjective	Verb	Adverb
lead poisoning	Yes	No	No	No
unwellness	Yes	No	No	No

As nouns, unwellness is a hypernym of lead poisoning; that is, unwellness is a word with a broader meaning than lead poisoning:

lead poisoning: toxic condition produced by the absorption of excessive lead into the system
unwellness: impairment of normal physiological function affecting part or all of an organism

Other hypernyms of lead poisoning include illness, malady, sickness.

lead poisoning (noun)	unwellness (noun)
toxic condition produced by the absorption of excessive lead into the system	impairment of normal physiological function affecting part or all of an organism