Dioxin and furan belong to a class of compounds known to have harmful effects on laboratory animals. Scientists believe they may also pose serious danger to humans. Lemieux and his colleagues are trying to determine how much burning in barrels contributes to dioxin and furan pollution. The polychlorinated compounds dioxin and furan can be created by burning common household trash at low temperatures. Years of research has determined that waste of this kind must be burned at a temperature of approximately 3000 degrees Celsius, and the resulting gases cooled to about 200 C and kept away from particulate to avoid the gas-solid reactions that create dangerous chemicals such as dioxin and furan.
Household refuse can include everything from paper to plastics to metals to organic waste.
Gases created by burning such waste include carbon dioxide, water vapor and nitrogen, while the particulate may include unburned carbon and traces of metals used to make wire, plastic products or dyes. Another principal culprit is an unidentified chlorine source. That is one of the pieces of the dioxin formation mechanism that is still unclear. The source of chlorine could be anything from salt to plastic polyvinyl chloride piping to bleached paper. Tests show that when trash is burned in a barrel, heat generated inside the container falls into the dioxin temperature window.