"Discarded automobile tires have become a serious health concern, largely because the growing number of stockpile fires has focused attention on the potentially harmful products of incomplete combustion (PICs) emitted into the atmosphere from burning scrap tires. This small-scale combustion study was designed to collect, identify, and quantify products emitted during the simulated open combustion of scrap tires. Fixed combustion gas, volatile and semi-volatile organic, particulate, and airborne metals data were collected under two burn conditions that varied by the size of tire material. Burn rates, varied by material size, were used to estimate potential emissions of identified products. Total estimated emissions of semi-volatile organics ranged from 10 to 50 g/kg of tire material burned. Mono and poly aromatic hydrocarbons were the main emission products identified. Benzo(a)pyrene (BAP) In particulate extracts is of particular concern because it is a known carcinogen. The presence of zinc in gaseous particulate collection was also verified and quantified. Several trends were evaluated relating emission products with burn rates."