Toxic Metal Contamination of Banked Blood Designated for Neonatal Transfusion

Objective: Very low birth weight (VLBW) infants frequently receive blood transfusions. We hypothesize that toxic metals in donor blood may pose a health risk with potential adverse neurologic effects on the developing brain of a vulnerable VLBW infant. Study design: Samples from 100 donor blood units were collected from a large urban hospital. Blood was analyzed for aluminum, arsenic, beryllium, cadmium, manganese, mercury, nickel, lead and polonium. The estimated upper limit of acceptable metal concentration in donor blood was calculated assuming a transfusion volume of 20 ml/kg and using either previously published acceptable intravenous doses or oral reference doses with a conservative estimate of 10% gastrointestinal absorption. Ingested mercury was assumed to be 95% absorbed. Results: Eight of the nine metals were detectable. Concentrations of arsenic, beryllium, cadmium, mercury and polonium were not of concern for any single blood transfusion. Concentrations of aluminum, manganese, nickel and lead exceeded the estimated upper limit of acceptable concentration in 5, 11, 4 and 26 units respectively. Of the 100 units, 31 had at least one toxic metal concentration high enough to pose a potential health risk. Conclusions: VLBW infants are exposed to heavy metals that are toxic from blood transfusion. The number of units with concerning levels of toxic metals was higher than expected. Neonatologists should be aware of this potential exposure to toxic metals from donor blood when decision is made to administer blood transfusion. Neurodevelopmental studies of toxic metal exposed infants from blood transfusion are warranted.