The amount of di-(-2 ethyl hexyl) phtalate (D.E.H.P.) is measured in the liquid contained in plastic bags or glass bottles for blood storage. Comparisons between the results show that D.E.H,P. has an equal level in plastic and glass container liquid except for one blood packs series. Particular attention has been paid to obtain solvents and glassware free from D.E.H.P., and to the specificity and the sensitivity of the detection method: a mass fragmentographic technic has been used.