What substance is formed when plastic burns?

When plastic burns, one of the harmful substances that can be emitted is hydrogen cyanide. This occurs due to the presence of nitrogen in many plastics, particularly those derived from synthetic materials. During combustion, the heat breaks down plastic polymers, and in the absence of sufficient oxygen, nitrogen combines with carbon to form hydrogen cyanide, a highly toxic gas.

Although carbon dioxide can also be produced when organic compounds burn, and certain types of plastics can release hydrochloric acid or acetylene, hydrogen cyanide is specifically noted for its high toxicity and is a significant concern in fire situations involving plastics. Thus, recognizing the potential hazards of hydrogen cyanide is crucial for firefighting and safety protocols.