The frequency of anemia is very high in very low birth weight (VLBW) infants in neonatal intensive care unit (NICU). Eighty percent of infants require at least one red blood cell (pRBC) transfusion because of repeated blood samplings for laboratory analysis, anemia of prematurity, infections, and bone marrow suppression due to antibiotics. In addition to several unfavorable effects of blood transfusions, heavy metal load via pRBC transfusions is not a well known entity. The aim of this study is to determine pre-and post-transfusion RBC lead and mercury levels in infants and the relation to pRBC units? lead and mercury levels. This prospective study was conducted between July 2011 and March 2013 in NICU of Hacettepe University Ihsan Dogramaci Children?s Hospital. VLBW infants who needed pRBC transfusion for the first time are included in the study. Two blood samples were obtained to determine RBC lead and mercury levels before and after the transfusion. Also pRBC units lead and mercury levels were determined. The quantity of transfused lead and mercury was calculated according to transfused volume and pRBC unit?s lead and mercury levels. The results were compared with the exposure reference values. Eighty infants met the inclusion criteria. The mean gestational age was 28.4±2.3 weeks and birth weight was 1083±256 g. Mean time for the first pRBC transfusion was 8.5 days after birth (8-22 days). Lead could not be determined in four samples and mercury in two of the pRBC samples due to hemolysis. Lead was measureable in all pRBC units and mercury was detected in 69.2%of them. The average lead and mercury levels in a pRBC unit were 16.3±10.8 µg/l and 3.75±3.23 µg/l respectively. The rate of infants who receive lead above the reference dose was 69.7%. Twenty seven percent of the infants received mercury above the reference dose set by Enviromental Protection Agency and 1.3%set by World Health Organization. In 68 enrolled infants whose pRBC unit, pre- and post-transfusion lead levels are obtained, average pre- and post transfusion RBC lead levels were 10,6±10.3 µg/l and 13±8.5µg/l respectively (p0.05). There was a weak correlation between the mean difference in pre-and post transfusion mercury levels and the amount of mercury delivered by PRBC units (r=0.28, p0.05). Transfüzyon sonrası ve öncesi ortalama eritrosit civa düzeyi farkı ile eritrosit süspansiyonlarıyla verilen kurşun dozu arasında düşük derecede korelasyon vardı (r=0.28, p=<0.05). Sonuç olarak, eritrosit süspansiyonlarının kurşun ve civa konsantrasyonları çok yüksek olmasa da bebeklerin önemli bir kısmında yaşamın kritik evresinde toksik dozda kurşun ve civa verilmektedir. Eritrosit süspansiyonları transfüzyon sonrası eritrosit kurşun düzeylerinde anlamlı yükselmeye neden olurken, eritrosit civa düzeylerinde anlamlı bir fark oluşturmamıştır
