Why Does My House Smell Like Burning Plastic?

It can be an electrical warning sign. The Consumer Product Safety Commission lists the smell of burning plastic at outlets or switches among the signs of electrical system problems, along with face plates on receptacles or switches that are hot to the touch, flickering lights and circuits that do not work. It says that if you notice any of these signs, a qualified electrician should determine the cause, and warns not to try to do it yourself because you could be electrocuted or make the problem worse. The US Fire Administration says an estimated 24,200 residential building electrical fires were reported to US fire departments in 2021, causing an estimated 295 deaths, 900 injuries and over $1.2 billion in property loss.

Burning plastic releases irritating and toxic gases. ATSDR says hydrogen chloride can be formed when many plastics burn, that it forms hydrochloric acid on contact with water, and that both are corrosive. It says hydrogen chloride gas can irritate the eyes, skin and respiratory tract, and that exposure to high levels can cause corrosive damage and could lead to fluid in the lungs and, in extreme cases, death. A 2019 study in the journal Toxics detected hydrogen chloride, vinyl chloride and other chlorinated compounds in emissions from burning PVC pipes, and found benzene, 1,3-butadiene, carbon monoxide, acrolein and formaldehyde at levels capable of affecting human health.

The CDC says the most common symptoms of carbon monoxide poisoning are headache, dizziness, weakness, upset stomach, vomiting, chest pain and confusion, and that they are often described as flu-like. A 2024 article in Annals of Global Health says few people realize the hazards of burning plastics such as polyvinyl chloride or Styrofoam, which release toxic dioxins, chlorinated furans or styrene gas when burned in the open, and that the toxicants released by burning plastics can linger even after the smoke and smell have dissipated.