Chemical, chain, china, maniac, manic, leach, lame, lane, cinema, nice, niche, came, calm, clean, mean, me, mice, malice, machine, mile, mine, ache, ace, aim, can, chime, ham, hem, helm, clam....fun one!!

Association

Ass, coats, action, scans, acts, coins, ants, scant, cost, into, icons, not, cots, sat, cats, tans, cans, cons, tons, snot, anti, tacos, antics, coast......

Disturbing

Stub, tub, tin, ring, in

Universe

Verse, serve, sever, never, nerve, vein,vine, veer, seen, see, even,ever, eve, seer, sere, vise, 

Contained

No, to, at, tan, do

contaminated

Ate, act, at, am, ad, aim, atom, con, came, come, code, cat, cad, on, omen, mint, mate, not, none, tame, tone, tan, time, taco, toad, toe, tonic, date, dote, dome, man, men, mine, mite, mane, mad, mat

digruntled

I’m assuming you meant disgruntled 

led, is, run, side, dig

Mismanaged

Oh, yes, I did. Forgot the “s”. 
 

miasma, mange, gain, gem, game, gin, dam, damn, sun, sign, man, men, manage, dame, dime

theoretical

Theoretical

the, or, thee, ethic, ethical 

pharmaceutical