Clinical waste comprises many materials, relatively few of which are classified as "hazardous waste" under EC legislation. Some prescription-only medicines (POMs) are an exception.
Burning hazardous waste fell under new controls this summer thanks to the 1994 EC Directive on hazardous waste incineration. The Directive requires operators to install more sophisticated monitoring equipment and introduces tighter emission limits and new controls on solid and liquid residues.
The Government introduced regulations to implement the Directive in 1998 (ENDS Report 279, pp 34-35 ). These brought clinical waste plants burning "hazardous waste" under the integrated pollution control (IPC) regime from 30 June 2000. Confusingly, however, clinical waste plants that do not burn "hazardous" POMs can continue to operate under the local air pollution control (LAPC) regime.
Adding to the murky picture, just because POMs count as "special waste" under British legislation they are not necessarily "hazardous waste". To fall under the EC definition, they must also exhibit properties such as toxicity and carcinogenicity. Forthcoming revisions to the EC hazardous waste list may further complicate the picture.
A more robust, and far less confusing, approach might have been to bring the incineration of all "special" waste under the new controls - but this would have added to NHS waste management costs and may well have proved unpopular with the Department of Health.
In spite of the Directive, around 30 clinical waste plants are continuing to operate under the LAPC regime, and only three have moved up to IPC. Clinical waste companies seem far from convinced that proper measures are in place to segregate hazardous POMs so that they are not burned in LAPC plants.
White Rose, the UK's largest operator, has four incinerators under IPC and six under LAPC. It has spent around £1 million to comply with the Directive's requirements.
Alan Esland, quality and technical manager, said that hospitals are responsible for segregating waste, placing it in separate, identified bins - but he does not believe they are doing the job properly. The company has issued guidance to its customers.
"Hospitals are very, very badly informed about hazardous waste - the Environment Agency should have done a lot more to educate them," he said. "Even some Agency staff don't know what 'hazardous' waste is." This means that LAPC incinerators may still be burning hazardous POMs, he believes.
Stephen Roscoe of waste business Grundon - operator of an IPC-regulated incinerator at Colnbrook, near Heathrow - said he "frequently has problems with poorly segregated waste." Although there are guidelines for hospitals, he doubted "whether this has permeated down to the doctors and nurses and other hospital staff."
Mark Olpin, operations director of Eurocare, which has an incinerator in Wrexham, said the company had spent more than £200,000 to comply with the Directive when it moved from LAPC to IPC. He has concerns that regulators are allowing other companies to continue to incinerate hazardous POMs under LAPC.
Numerous technical upgrades have been required under the Directive - including optimising the combustion process, improved gas cleaning, fitting continuous monitoring equipment and monitoring for extra substances such as VOCs and HCl.
The Agency has demonstrated some appetite to enforce the new controls on plants that have recently upgraded to IPC. In October, failure to ensure that new monitoring equipment worked effectively led to an enforcement notice - since lifted - being served on Eurocare to prohibit hazardous waste.
One way of implementing the Directive more robustly would have been for local authorities to set conditions in LAPC authorisations prohibiting combustion of "hazardous" waste. But Mr Esland told ENDS that only one of White Rose's six LAPC authorisations has any such condition.
For the Agency, Martin Whitworth accepted that the regulatory picture was rather complex, giving rise to a "very confusing state of affairs" on POMs. But he insisted that Agency guidance had put in place a mechanism which ensured appropriate regulation.
Mr Whitworth would not be drawn on whether some companies were continuing to burn hazardous waste under LAPC, except to say that the Agency would take action against any operation that did not have the correct authorisation.
The Department of the Environment, Transport and the Regions told ENDS that it had not told local authorities to include "any particular conditions not to accept POMs" in LAPC authorisations.
"We are relying on the Agency to ensure that it regulates all processes it is required to, and on the sanctions on operators of clinical waste incinerators which burn hazardous waste and fail to obtain an IPC authorisation," the DETR said.