Incineration is another form of plastic waste disposal that has proven to be both ineffective and harmful to the environment. Incineration has come under increasing environmental regulatory restrictions in most countries in order to prevent unforeseen impact on human health and the environment. These risks and concomitant restrictions have forced the number of incinerators in the United States to decline from a peak of 186 in 1990 to a low of 89 in 2007.

Incineration does eliminate plastic waste, but in doing so it creates hazardous atmospheric emissions and toxic ash. When incinerated, plastic emits carcinogenic, toxic, and noxious pollutants into the air, land, and water, as well as an extremely high volume of greenhouse gases, such as carbon dioxide. In terms of emissions, the volume of pollutants released is directly comparable to that released by the burning of fossil fuels. The toxic ash created causes further hazards when used (as it typically is) as routine landfill cover.