What is defined as the combustion of waste in open air, often resulting in airborne pollutants?

The correct term for the combustion of waste in open air, which often results in airborne pollutants, is indeed open burning. Open burning refers to the process where waste materials are burned in outdoor settings without the use of pollution control equipment or measures. This practice can lead to harmful emissions, including particulate matter and toxic compounds, and is often uncontrolled, making it a significant environmental and public health concern.

On the other hand, controlled incineration involves the burning of waste in a facility designed with pollution control technologies that minimize harmful emissions. Landfill disposal refers to the burying of waste in designated sites, while thermal treatment encompasses various high-temperature processes aimed at reducing waste volume and toxicity, but typically involves controlled environments rather than open air burning. Each of these alternatives has regulations and controls that open burning lacks, which is why open burning is particularly associated with negative environmental impacts.