Objectives: 1) to determine zinc and copper levels of contamination in the individual component solutions used to prepare the pediatric total parenteral nutrition mixtures in Argentina; 2) to compare zinc and copper amounts prescribed by the physician with the true amount given to a neonate weighing 1.2 kg and to a child weighing 10 kg, who would receive total parenteral nutrition formulas prepared with those component solutions.
Materials and methods: Zn and Cu were determined by atomic absorption spectrophotometry in 59 individual solutions belonging to 14 components chosen between the commercial products available in Argentina.
Results: zinc and copper, as contaminants, were found neither in the sterile water, nor in the potassium chloride or in the vitamin solutions. Zinc, but no copper, was detected in sodium chloride, manganese sulfate, chromium chloride and seleniose acid solutions. Zinc and copper were detected in dextrose, amino acids, calcium gluconate and lipid solutions at variable levels. Zinc sulfate solutions contained between 90.4% and 140% of the declared content and a variable contamination with copper. Copper sulfate solutions presented between 4% and 18% less the declared copper concentration and a variable contamination with zinc. Dextrose and lipid solutions presented the highest amount of zinc and copper. Therefore, the total parenteral mixtures prepared with the analyzed solutions must have had an excess of zinc and copper in relation to the prescription: ranging between 103% and 161% and between 7%-426% higher than the Zn and Cu amounts prescribed for neonates, respectively; the excess in the total parenteral nutrition for a child weighing 10 kg would ranged between 105% and 189% and between 7%-365% higher than the prescribed for Zn and Cu, respectively.
Conclusions: 1) Nine components presented Zn and five Cu, both of them not declared in the label; 2) the usually prescribed total parenteral nutrition mixtures must have had a zinc and copper amount higher than the prescribed one according to international recommendations; 3) those figures would be safe in patients without complications, but it would be harmful in renal failure, hepatic compromise or colestasis mainly in pediatric patients; 4) It would be advisable to declare in the label the true content of zinc and copper, with the aim to avoid deficiencies and excess which would compromise the evolution of pediatric patients.