He stated, 'in substance' [='in essence', 'essentially'], that it is not his fault and he will not pay for damages.
These rumors have no 'substance'. = These rumors are 'without substance'. [=these rumors are not true]
Codeine is a 'controlled substance'. [=a drug that you need permission from a doctor to use]
(..) they're just meteorites. Fair enough. But the level of specific radioactivity... ...is so high to anyone from the planet Krypton... ...this substance is lethal. Wait a minute, Mr. Luthor. Fire and bullets can't hurt this guy... ...but this stuff here... ...will kill him. (..)1978 Superman