COMPARISON OF PROPYLENE-OXIDE AND EPICHLOROHYDRIN EFFECTS IN 2 TRANSFORMATION TESTS (C3H 10T1/2 AND SHE CELLS)/

The neoplastic cell transformation induced by propylene oxide (PO) and epichlorohydrin (ECH) was studied in two in vitro assays, mouse embry o fibroblasts (C3H/10T1/2) and Syrian hamster embryo (SHE) cells. In C 3H/10T1/2 cells treated with PO (2.5-10 mM), the transformation freque ncies were enhanced about 2-4 times in the presence of 12-O-tetradecan oylphornol-13-acetate (TPA), compared with the transformation frequenc ies in the absence of TPA. In SHE cells, an even higher increase (abou t 6-9 times) was reached at concentrations of 2.5-20 mM. The presence of TPA strongly influenced the ability of ECH to induce the morphologi cal transformation at low-moderate concentrations (0.25-1 mM). At the highest concentrations applied, 1 mM in C3H/10T1/2 cells and 0.5 mM in SHE cells, 41- and 4-fold increases, respectively, were observed. In C3H/10T1/2 cells, the rad-equivalence (rad/mMh) of PO and ECH in the p resence of TPA was calculated to be 36 +/- 8 and 296 +/- 65 (mean +/- S.E.), respectively.