Although additional controls on incinerators can dramatically reduce what comes out of the stack, the only way to really prevent mercury pollution is to get mercury out of products. And plenty of hospitals are leading the way in that effort. Similarly, products containing cadmium and other heavy metals end up going out the stack when burned, so changing the materials used is important. PVC or vinyl plastic is another problematic material which dominates the hospital waste stream. The emergence of vinyl as an important plastic, and the increasing use of disposables in the hospital waste stream have combined to make polyvinyl chloride plastic a major problem in hospital waste.
Chlorinated products are an essential element in the formation of dioxin during incineration.
PVC is also very toxic in its production. Removing PVC from the waste stream would dramatically reduce dioxin released from the incinerator. Like mercury, controls may reduce the dioxin emitted, although increasing amounts are then captured in the ash which is then sent to a landfill. The U.S. Environmental Protection Agency issued final standards for air emissions from medical waste incinerators in August of last year. In 1990, the EPA was given two years to promulgate rules.