A scientific committee said a stockpile of about 500 tonnes of blubber in freezer warehouses in northern Norway contained dangerously high levels of banned PCB industrial chemicals.

"Human consumption of whale blubber would lead to unacceptable levels of PCBs," Janneche Utne Skaare, deputy director of the National Veterinary Institute and a scientist on the panel, told Reuters.

PCBs, or polychlorinated biphenyls, were formerly used in everything from paint to plastics. They build up in fatty tissues, especially in people and animals in polar areas and have been linked to birth defects.

Oslo resumed the commercial hunting of minke whales in 1993, breaking with an international moratorium. The creamy fat was long seen as a potential goldmine if exported to Japan, where it is a delicacy worth perhaps $20 per kg (2.2 lbs).

Whalers conceded that the scientists' recommendation to ban blubber consumption among Norwegians - which has to be approved by health authorities - would scupper hopes of selling the fat to Japan. Norwegians only eat minke whale meat, which has far lower PCB levels than fat.

"The whalers will probably go back to dumping the blubber overboard," said Rune Froevik of the High North Alliance, which represents interests of Arctic fishing communities. "It'll be crab food."

Other possible uses for blubber are in heating oil, food for foxes and other animals in fur farms.

After limiting whale consumption to Norwegians, Oslo gave whalers permission to export minke meat and blubber in 2001 in defiance of a ban on trade in endangered species.

Since 2001, whalers have exported some meat to Iceland but blubber exports have been stalled by demands for a genetic tracking system and by Japanese consumer worries that whales caught in the North Atlantic have high PCB levels.

Skaare said that Norwegian tests showed that one gram (0.035 ounce) of minke blubber had about 95 picograms of PCB-related pollutants, almost a tenth of the maximum weekly intake under European Union guidelines. A picogram is a trillionth of a gram.