Compatibility of plastic infusion devices with diluted N-methylformamide and N,N-dimethylacetamide

Leaching of the plasticizer di-2-ethylhexyl phthalate (DEHP) from i.v. sets and polyvinyl chloride bags was studied with solutions of a new anticancer drug, N-methylformamide (NMF), and N,N-dimethylacetamide (DMA), a structurally related solvent used in the formulation of some anticancer drugs. Solutions of 0.9% sodium chloride, 5 and 10% DMA in 0.9% sodium chloride, and 20, 40, and 60% NMF in 0.9% sodium chloride were used to fill i.v. administration sets ( Venoset -60, Abbott Laboratories) and polyvinyl chloride bags ( Viaflex -500, Travenol Laboratories). The solutions were kept in the containers for 20 hours at ambient temperature. Simulated infusions were also studied using 0, 20, and 40% NMF plus 5 and 10% DMA in 0.9% sodium chloride; both glass bottles and Viaflex -500 bags were used with the i.v. administration sets. DEHP was assayed using gas chromatography. Very small or unmeasurable amounts of DEHP were leached into 0.9% sodium chloride and 5 or 10% DMA solutions during 20-hour storage. DEHP concentrations increased exponentially with increasing NMF concentrations after 20-hour storage in both the i.v. sets and bags. Similar results were found in the simulated-infusion portion of the study. DEHP extraction from i.v. sets and polyvinyl chloride bags containing NMF and DMA in 0.9% sodium chloride is related directly to the concentrations of these organic compounds. The amount of DEHP leached into solutions is important only for solutions containing 60% NMF.