Lipstick Evidence

It turns out collecting lipstick evidence at a crime scene, whether off a paper cup, cigarette butt or piece of clothing, is a difficult and tedious process. So most lipstick brands are identified while still on the object using complex techniques—an expensive and tricky process.

Bellott’s team first examined current methods of lipstick extraction, whittling away unnecessary steps and experimenting with new solvents. The result? A two part process in which one chemical removes oils and waxes from the lipstick and then a different compound captures the remaining lipstick residue. This residue can be analyzed using a method known as gas chromatography—which is relatively inexpensive and does not require extensive training.

Since each brand of lipstick is composed of a unique array of organic molecules, brands leave a revealing ‘chemical fingerprint.’ Bellott and his colleagues compiled a database of 40 different lipstick brands, which crime scene investigators can eventually use to identify the maker of lipstick marks.

https://www.smithsonianmag.com/smart-news/csi-sephora-new-technique-helps-identify-lipstick-brands-crime-scenes-180958451/#cbzjV1CwESijMEez.99