The federal office for agriculture has sought to reassure members of the public after a seizure of flour last week was found to have contained traces of bone meal.

Manfred Bötsch, director of the agriculture office, told Swiss radio the government has a policy of "zero tolerance" towards mills found to be producing contaminated flour.

Bötsch also defended the government's decision to seize 65 tonnes of flour from Intermill in canton Aargau, and cautioned that further discoveries of contamination could not be ruled out.

"One hundred per cent security simply does not exist," he said.

Under Swiss law, animal feed containing bone meal has been outlawed since the beginning of this year after it was named as a possible source of mad cow disease, or BSE (Bovine Spongiform Encephalopathy).

The veterinary office said the tainted samples, along with all lots of flower delivered by the mill, have been impounded and a large-scale investigation is underway.

Question of blame

The owners of the mill currently under investigation have rejected all responsibility for the contamination, laying the blame at the government's door.

In a statement released last week, the owners of the mill - located in the village of Schöftland - claimed the contamination must have happened during transit, because its grinding equipment had not come into contact with tainted flour.

Bötsch, however, questioned this immediate rejection of responsibility, saying the mill was attempting to clear its name.

"When it comes to addressing the question of who is to blame, they should be more careful, " Bötsch added.

swissinfo with agencies

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