Mr. Chairman, honourable committee members, fellow witnesses, ladies and gentlemen, I'd like to thank the committee members for inviting me to speak here today.
My name is Dr. Mindy Goldman, and I'm an executive medical director with Canadian Blood Services.
I consulted my colleagues at Héma-Québec. I'm here today representing Canada's two suppliers of blood.
I was a member of the Health Canada expert advisory committee panel on DEHP and medical devices, as was Dr. Khatter, I think. I'm here to address four words in the bill: other than blood bags. I hope that's all I'm supposed to address.
Blood is collected in sterile, single-use plastic collection sets, and it's then separated into different components. The main components are plasma, platelets, and red cell concentrates. Because plasma is stored frozen there is no leaching of the DEHP from the plastic into the product during storage. Most platelet storage bags do not contain DEHP. In addition, platelets can only be stored for five days, so there's very little time for the DEHP to leach into the component.
Red cell components, however, are stored at one degree to six degrees for up to 42 days, and these conditions do permit substantial leaching to occur. The concentration of DEHP increases with the length of time of storage. Interestingly, DEHP plays an important role in the actual survival of the red blood cells themselves. Currently, red cell components can be stored for 42 days, or six weeks. Without DEHP, storage beyond 21 days, or three weeks, is not possible. Such a reduction in storage period would have a major impact on blood inventory and availability. Other plasticizers do not have the same stabilizing effect on the red cell membrane.
Based on animal toxicity data, the Health Canada expert advisory committee considered that newborns, infants, and young children receiving large amounts of red cells would be at greatest risk for possible transfusion-related DEHP toxicity. Unfortunately, there have been few studies evaluating long-term DEHP toxicity in transfusion recipients.
One study published in the journal Environmental Health Perspectives in 2004 followed adolescents exposed to very large amounts of DEHP as neonates, and found normal growth and endocrine function. However, although the study was reassuring, the small number of patients involved does not really permit firm conclusions about the lack of toxicity of DEHP.
The Health Canada expert advisory panel made several recommendations that are relevant to blood transfusion. Following the recommendations, both Canadian Blood Services and Héma-Québec added a section to our circular of information, just like our product insert, that we distribute to our hospitals about DEHP. Physicians are advised to select fresh or red cell components that would contain less DEHP for large-volume transfusions in susceptible populations, and to remove some of the liquid part of the red cell component prior to transfusion to further reduce the amount of DEHP present.
The Canadian Pediatric Society recommends the use of fresh or red cell components for large-volume transfusions in these patient groups for various reasons, including reduced DEHP exposure.
In summary, DEHP is present in certain blood components, particularly those containing red blood cells. It is essential for the preservation of red blood cells for up to 42 days. Both information from the blood suppliers and recommendations from professional organizations attempt to reduce DEHP exposure in the most vulnerable patient groups.
Thank you for your attention.