Following full combustion, the only residues are carbon dioxide and water. While carbon dioxide can induce suffocation, incomplete combustion generates carbon monoxide, a toxic agent. Moreover, hydrocarbons may undergo incomplete combustion, potentially converting carbon dioxide back into carbon monoxide.
The predominant symptoms of carbon monoxide poisoning are dizziness, headaches, lethargy, and an intoxication-like state, with severe exposure potentially resulting in unconsciousness.