The sorption of hexyl acetate and ethyl butyrate into polypropylene from vapors and 40% ethanol solution was studied. The effect of concentration and interactions with co-sorbants was investigated. The vapors were sorbed in amounts that were related to feed concentrations, without any interactive effects of co-sorbants, in the concentration range (i.e. 0.12-3.4 ?g/mL) and the mixtures investigated Compounds from a dissolved mixture, on the other hand, were generally sorbed in smaller amounts than from a single compound solution. Hexyl acetate was sorbed in larger amounts from a mixture of five compounds at high concentration (i.e. 1000 ?g/mL each) than when it was the sole solute.