A mixture of poly(vinyl halide) and epoxidized benzyl fatty acid ester, preferably epoxidized benzyl soyate (EBS), is disclosed. The epoxidized benzyl fatty acid ester as a plasticizer replaces common high molecular weight phthalates, such as diisodecyl phthalate (DIDP), which are conventionally used for the manufacture of wire and cable insulation and jacketing. The epoxidized benzyl fatty acid ester, a bio-plasticizer, unexpectedly outperforms the higher molecular weight DIDP as demonstrated by superior retention of Strain at Break after accelerated aging at elevated temperatures.