When producing a cosmetic cream using hemp seed oil, they probably do not use the original, virgin seed oil, but convert it before introduction it to cream manufacture.
Hemp seed oil contains high content of organic acids, which have not a favourable action on skin due to their acidity. The virgin hemp seed oil is therefore treated with ethanol to convert the acids to esters. The excess ethanol, which is used in this conversion step, is removed by destillation in vaccum. During the removal of the excess organic solvent, all other volatile constituents, predominately the cannabinoids, are also destilled away due to their volatile characters. The residue, which contains mostly the fatty acid esters is than used with favourable action in the production of skin creams.
The level of cannabionoids in cosmetics therefore is reduced um serveral levels, and this contributes additional to the product safety of the skin creams.
If there are remaining very, very low levels of cannabinoids in the hemp seed oil preparations, they might have a synergistic effect on the "feeling of the cream" on a human skin. The action can be considered to be synergistic to a smoothing, relaxing feeling. These remaining levels of cannabiniods in skin creams are still much too low to produce a considerable level in a users' urine, not compareable to those levels when smoking a MJ cigarette.