A NORTH-EAST woman has warned US officials that their country's blood and plasma supply could be contaminated with the human version of mad cow disease.

Written evidence from Carol Grayson, from Jesmond, Newcastle, has been submitted to the US Food and Drug Administration (FDA).

Her letter was included in material presented to the agency's transmissible spongiform advisory commiteee, when it met in Silver Spring, Maryland, two days ago.

Apart from concern at US blood supplies being contaminated, Mrs Grayson is also worried about the safety of US plasmas imported by the UK, because of fears that the British supply could already be contaminated with variant Creutzfeldt Jacob Disease, or vCJD.

Mrs Grayson, whose husband, Peter Longstaff, 43, is a haemophiliac who is said to be showing the first signs of vCJD, told the FDA that she knows of cases in which European and UK nationals, who could be harbouring vCJD, have donated blood and plasma in the US while visiting as students or tourists.

vCJD is an incurable brain disease, which is believed to be contracted from eating beef products contaminated with mad cow disease, also known as bovine spongiform encephalopathy, or BSE.

"I am aware that over the years ,citizens from European countries with cases of BSE/vCJD have sold their blood in the US and been accepted as donors," her letter said.

"Even if this practice has stopped, if vCJD is transmittable via blood products, is there not a risk that vCJD could already have been in the blood supply and that American recipients may be incubating vCJD?" Mrs Grayson asked.

The TSE advisory committee will consider whether FDA policies for blood donors are adequate to ensure the safety of the US blood supply. This follows two recent cases in the UK of people developing vCJD after blood transfusions.