An in vitro evaluation of a new plasticizer for polyvinylchloride medical devices

The rate of Hatcol-200 (H-200) leaching from polyvinylchloride (PVC) by serum is one-hundredth that of di-2-ethylhexyl phthalate (DEHP) as determined by radioassay. There is a proportional decrease in leachability of DEHP but not of H-200 as the plasma proteins are diluted. Saline extracts of DEHP demonstrated a low but progressive rate of leaching with an accumulation of 11 microgram/ml after seven weeks whereas H-200 showed only a constant residue of 0.35 microgram/ml. Normal human serum incubated for three weeks at 37 C with PVC strips plasticized with DEHP produced significant growth-inhibition of human diploid fibroblasts. Human serum incubated in an identical manner with PVC plasticized with H-200 for up to four weeks demonstrated no effect on tissue culture. These studies indicate that H-200 deserves further evaluation as a replacement for DEHP in PVC biomedical devices.