FILE-- Cheryl Calaminici donates platelets at Canadian Blood Services in Toronto on in this April 10, 2006 file photo. Canadians donated 850-thousand units of whole blood last year but it all came from just 3.7 per cent of the population. With just a fraction of Canadians donating blood, Canada may be headed for a supply crisis in the future. (CP PICTURE ARCHIVE/Frank Gunn)