A SPECIAL international licence will be required to export for testing the contaminated oil thought to be responsible for the dioxin pork scare.
Sources close to the investigation confirmed yesterday the oil, believed to have come from electricity transformers, can only be exported to another country under special licence because of its toxicity.
Waste oil from the electricity transformers and switching gear containing high levels of PCBs is normally exported under special licence for destruction from the island of Ireland.
The best, most widely-used and proven technology for destroying PCBs is high-temperature incineration at temperatures greater than 1,200 degrees.
Properly done, this has been shown to destroy PCBs at an efficiency of 99.9999 per cent, leaving an inorganic ash.
Smoke stack "scrubbers" are used to remove the hydrogen chloride gas and other compounds which can be formed as byproducts of combustion.
Alternatives to incineration include chemical treatment for mineral oils to destroy low levels of PCBs in some of the waste oils and bacterial treatment.
The food recycling facility at the heart of the scare, Millstream Recycling, said in a statement it has "only ever purchased oil from a legitimate supplier in the Republic".
Meanwhile, the investigation into the source of the contaminated oil by the Environmental Protection Agency and the Garda is continuing.
Queries on the progress of the investigation to the EPA and on the special licence requirements for exporting the oil samples were not answered.
The Health and Safety Authority has not yet been called in to investigate if workers or others at the Millstream plant near Bunclody, Co Wexford, have suffered any ill-effects from the process which contaminated the pig feed.
It is believed fumes from the oil used in the process of heating the feed - which was mainly dough and stale bread, biscuits and chocolate - contaminated the product, known in the trade as "cake".
Tests on some of the 9,000 cattle locked up on 45 farms to determine the levels of exposure to the contaminated feed will now not become available until tomorrow.
These are being handled by the Food Safety Authority of Ireland, which had said at the weekend the tests would be available today.
It is understood the tests are not being fast-tracked through the system because all the cattle involved are restricted and will remain so until all testing is completed.
Talks with the owners of the 10 pig farms hardest hit in the crisis, which saw a temporary closing down of the processing sector, will continue today with the Department of Agriculture.
All 100,000 pigs on the farms affected will be killed and their carcases incinerated in rendering plants which deal with specified risk material from the cattle and sheep industry.
The pig producers are seeking compensation for the loss of their stock.