§ Mr. Canavan
asked the Secretary of State for the Environment whether he has any information as to the relative amounts of furans and dioxins produced (a) when batches of polychlorinated biphenyls are incinerated in drums and (b) by continuous liquid feed of polychlorinated biphenyls to an incinerator.
§ Mrs. Rumbold
No relative data are available since PCBs are not normally burnt in drums.
Trials have demonstrated that the amount of dibenzofurans and dibenzodioxins emitted as a result of high temperature incineration of PCBs by continuous liquid feed is consistently less than 1 part in 10 12 (ie one in a million million) in stack gases.