Formation of dioxins from incineration of foods found in domestic garbage

There has been great concern about the large amounts of garbage produced by domestic households in the modern world. One of the major sources of dioxins (PCDDs, PCDFs, and coplanar PCBs) in the environment is the combustion of domestic waste materials. Exhaust gases from an incinerator, in which mixtures of 67 food items-including fruits, vegetables, pasta, Seafoods, meats, and processed foods and seasoned foods-were analyzed for dioxins. Gases collected at the chimney port (9.15 ng/ g) contained less total dioxins than those collected at the chamber port (29.1 ng/g). The levels Of Cl-1-Cl-6-PCDDs and Cl-1-Cl-5-PCDFs were much lower in the gas collected at the chimney port than in the gas collected at the chamber port. The levels Of Cl-7-Cl-8-PCDDs and Cl-6-Cl-8-PCDFs were higher in the gas collected at the chimney port than in the gas collected at the chamber port. A total of Cl-4-Cl-8-PCDDs (1.84-3.04 ng/g) comprised over 80% of the total PCDDs formed (2.24-4.00 ng/g). Total PCDFs (16.2-22.6 ng/g) comprised 78-86% of the total dioxins formed (18.9-29.1 ng/g). The PCDFs formed in the greatest amounts were M(1)CDFs (9.68-10.7 ng/g). Mixtures of commonly consumed food items produced ppb levels of total dioxins in exhaust gases upon combustion, suggesting that incineration of domestic food wastes is one of the sources of dioxins in the environment. A mixture containing some seasoned foods, such as mayonnaise spread on bread, produced more dioxins (29.1 ng/g) than a mixture without seasoned foods did (18.9 ng/g).