A transformer vault that supplied power to a pesticide storage warehouse caught fire. The warehouse also caught fire. A river was located adjacent to the warehouse which was the source of drinking water for a town downstream of the warehouse. The transformer contained 600 gallons of the Askarel material PCB. The warehouse contained 100 drums of the herbicide Gramoxone, 50 drums of the herbicide Agent Purple and 75 drums of the insecticide Guthion. Through combustion, products of complete and incomplete combustion are produced which will affect firefighters and the environment. Polychlorinated Biphenyl (PCB) is widely used for dielectric and coolant fluids in transformers, capacitors, and electric motors. Its configuration is 2 to 10 chlorine atoms attached to biphenyl. The chemical formula for a PCB is C12H10-xClx. PCB is extremely hazardous. It can be absorbed through the skin, causing a skin rash called chloracne, liver damage and increase of fat in the blood. Individuals can be exposed to PCB's through breathing in contaminated air, consuming contaminated food, and by skin contact with old electrical equipment containing PCB. Scientists discovered that once ingested PCBs migrate into various receptor tissues of the thymus, lungs, spleen, kidneys, liver, brain, muscles, and testes. Children exposed to high levels of PCBs during their mothers' pregnancy often have reduced motor skills and short-term memories. By conducting experiments on animals, scientists have discovered that PCB exposure over long periods induces the formation of malignant tumors in the liver, mouth, adrenal, glands, and lungs. The OHSA permissible exposure limit (PEL) is 1mg/m ³. The LD50 to kill a rat is 8.65g/kg. For drinking water the maximum level contamination of PCBs is .0005 ppm. And for food, the tolerance levels of PCBs is 0.2 and 3 ppm. When PCB's are involved in a fire, toxic by-products of combustion are usually produced including polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzodioxins (PCDDs). Some of these compounds are more toxic then PCBs and can may the main hazard from a PCB fire. Dioxins have been considered highly toxic and able to cause reproductive and developmental problems, damage the immune system, interfere with hormones and also cause cancer. Dioxins formed during the burning of fuel and wastes are released into the air. Soil near the burn areas also may be contaminated with dioxins. Dioxins enter a persons body from the ingestion of food, particularly through the consumption of fish, meat, and dairy products since dioxins are fat soluble and readily climb the food chain. Dioxins are can be passed down to children through breastfeeding. Dioxins build up primarily in fatty tissues, so even small exposures may reach dangerous levels. Dioxins are easily absorbed by animals and are stored in fatty tissue. Exposure to high levels of dioxin can cause chloracne. Some other effects in humans at high dose levels include diabetes, thyroid disorders, and damage to immune systems. The LD50 of dioxin varies wildly between species with the most notable difference being between the ostensibly similar species of hamster and guinea pig. The oral LD50 for guinea pigs is as low as 0.5 to 2 μg/Kg body weight, whereas the oral LD50 for hamsters can be as high as 1 to 5 mg/Kg body weight. Polycyclic aromatic hydrocarbons (PAHs) can be released into air, water and soil. The effects on human health depend on the concentration of PAHs and the type and extent of exposure. Health effects from chronic or long-term exposure to PAHs may