Toxicological quandary of the use of bis (2-diethylhexyl) phthalate (DEHP) as a plasticizer for blood bags.

Plastic bags are very useful containers for the storage of blood and blood products since they are relatively transparent, hard to break, can be sealed aseptically with a radio-frequency current, and can be centrifuged for the isolation of blood components. In order to make the plastic more flexible, various agents are added, of which the most common is di- (2-ethylhexyl) phthalate (DEHP). This plasticizer has been found to leach from the plastic into the blood components during the storage period. Some animal studies have shown that this chemical can produce cancers and various tissue abnormalities. The human data from multi-transfused patients do not clearly indicate any specific damage: however, because of the animal studies, work has been carried out to find a non-leachable plasticizer. Several have been found: unfortunately, when survival studies are done, the red cell life span of the stored blood is decreased. Current work seems to indicate that DEHP has a membrane stabilizing function that prolongs the storage time of the red cell. Therefore, there currently is a trade off between plasticizer presence and red cell life span that must be considered when designing new blood storage bags.