Dioxins and fLirans. two deadly by- products of medical waste incineration, form directly from chlorine and chlorinated products which are present in much larger volumes in medical wastes than in municipal wastes. Chlorinated products in medical wastes would typically include catheters, gloves and blood bags. A two year study conducted by the Danish National Environmental Research Institute in 1990 found that hospital wastes contributed 30 per cent of the dioxins and furans produced in Denmark, although it made up only one per cent of the total waste produced in the country.

Dioxins are well documented animal carcinogens and are considered human carcinogens as well. A comprehensive health risk assessment of medical wastes incineration conducted by the California Department of Health Services along with the California Air Resources Board in 1990 stated that the most significant cancer effects came from dioxins and metals like cadmium.

Usually, the disposal of incinerator ash from medical wastes having high concentration of heavy metals, dioxins and furans is not properly monitored. The ash is dumped in a landfill, where it is rarely or insufficiently covered with inert material. As a result, groundwater pollution occurs through leaching. Dioxins and furans found in the incinerator ash are at levels of the order of micrograms per gram of ash.