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Example(s) of typical appearance
Example(s) of a change in appearance

Bacterial contamination is the presence of bacteria in the blood. Blood should be free of bacteria. Blood is collected and processed under sterile conditions to maintain this aseptic state. Pathogen inactivation through psoralen treatment further reduces the risk of bacterial contamination in platelets. All platelet units not treated with psoralen are tested for bacterial contamination by Canadian Blood Services. Bacterially contaminated blood components should NOT be transfused and any components suspected of bacterial contamination based on a visual inspection, must be reported to Canadian Blood Services using the feedback form on blood.ca. Contact the nearest distribution centre to report potential contamination and receive further instructions. 

Possible (though rare) sources of bacterial contamination include the following:

  • Donor with asymptomatic bacteremia (i.e., subclinical bacteria in blood)  
  • Inadequate cleansing of skin prior to venipuncture. (Please note: To minimize bacterial contamination, Canadian Blood Services uses a diversion pouch for the first portion of the blood donation. In addition to a strict protocol on skin cleansing, the diversion pouch prevents the skin plug and skin bacteria from entering the main unit.)
  • Loss of sterility during component manufacturing or handling. 

Visual appearance 

  • The presence of bacteria may produce gas resulting in excessive air bubbles. 
  • The presence of bacteria may activate clotting resulting in clots and fibrin strands. 
  • Cloudiness 
  • Grey discolouration