Trace element contamination of total parenteral nutrition. 1. Contribution of component solutions.

Background: Trace elements have been shown to contaminate total parenteral nutrition (TPN) solutions.

Methods: This study used the multi-elemental technology of inductively coupled plasma-mass spectrometry to demonstrate the extent to which trace elements were present in amounts above (ie, as contaminants) or below expected levels in eight TPN component solutions.

Results: Of the 66 trace elements scanned, there were 12 trace element contaminants in amounts >1 microg/L (zinc, copper, manganese, chromium, selenium, boron, aluminum, titanium, barium, vanadium, arsenic, and strontium) in the eight component solutions studied. Trace element contaminants were present in all solutions, and different trace elements contaminated the solutions at various concentrations. Component solutions of amino acid, potassium chloride, calcium gluconate, and sodium chloride contained the greatest numbers of trace element contaminants, whereas the lowest numbers were present in sterile water and magnesium sulfate. Interlot and intermanufacturer variations were apparent. Measured concentrations of trace elements in the multi-trace element additive solution also were higher than the labeled values. A comparison of the amounts of contaminated trace elements delivered by a typical TPN mixture relative to the amounts typically absorbed by the gastrointestinal tract indicates that the inadvertent delivery of trace elements from contaminated TPN solutions may be substantial.

Conclusions: All eight components tested were contaminated with trace elements not intended to be present in the product, and similarly, the multi-trace element component contained trace elements either above or below that which the label claimed.