Super Glue Fuming

Did you know that “Super Glue” has a place in forensic science?

The glue commonly known as “Super Glue” or “Krazy Glue” is actually a substance that is chemically known as Methyl-2-cyanoacrylate. Another version of this glue is also known as 2-octyl-cyanoacrylate which is a medical glue with common names of “Dermabond” and “Traumaseal.”

Cyanoacrylate, or “CA” as it’s sometimes called, is able to stick a lot of things together including skin. But it also has a unique property to help “develop” fingerprints that are left on certain objects. When left uncovered in a slightly moist environment, the glue gives off a fume that attaches to fingerprints and “fixes” the print in place. Once developed, it leaves a white residue on the surface where the print is found. This can then be “dusted” with fingerprint powder and then “lifted” with fingerprint lift tape and then placed on a latent fingerprint card for comparison.

If you’ve ever looked at the inside of the plastic bubble packaging that Super Glue often comes in, you might have noticed some white powdery stuff inside… often looking like someone’s fingerprint. Well, guess what? :)

For forensic work, the CA comes in thin pouches about the size of a 4x6 photo. The glue is spread out across the inside of the front and back of the pouch which is exposed when the pouch is pulled open. Typically, for small items like handguns or soda cans or similar items, a 10 gallon glass aquarium with a lid might be used as a container to perform the fuming. A small jar of warm water is placed inside along with the item being fumed. After about 15-20 minutes, you can often see the white powder forming on the objects inside. Once the glue has “fixed” the prints, it’s there for a long time. Not only can the prints be photographed, dusted and lifted, but it can be done several times as well.

I’ve done my fair share of dusting evidence for prints… probably covering thousands of evidence items. But Super Glue fuming is one of my favorite ways to get a print off of things like guns, soda cans and plastic items.

I also recall placing several packets of Super Glue inside a van that we pulled out of the Chula Vista harbor one day. The vehicle was found partially sunken in the boat dock with the body of a woman inside. After pulling the van out of the water with a tow truck (and of course removing the body) we towed the vehicle back to the police department and used the Super Glue to try to develop fingerprints inside the van. We just rolled up the windows and placed the glue inside to do the job. Worked great!

To see a sample of what these Super Glue packets look like, visit this site.

More fingerprint techniques in future postings here. Keep visiting daily! :)