LC3 Forensic Toxicologists

Some of the LC3 girls had the opportunity to experience a day in the life of a forensic scientist last Saturday as part of their Chemistry activity, where they recovered latent fingerprints from drinks cans.

Latent fingerprints are fingerprints that you cannot see with the naked eye. Fingerprints are developed inside the womb at five months gestation and are unique to each individual, even identical twins who will share the same DNA. Therefore they hold great evidential value. 

There are many characteristics that forensic scientists can identify within a fingerprint, to help compare a set of prints. The girls were taught about how fingerprints are taken from everyone who has ever been arrested for a crime and that these prints are held in a central database, which forensic scientists can use to make comparisons. We discussed that one main limitation is that this database is of no use for first-time offenders.

The LC3 girls collected their own sets of fingerprints, using the ink pads the police use when they arrest someone, and then observed them under a hand held microscope to see the specific characteristics identified by forensic scientists.

After this, the girls then deposited a fingerprint on a drinks can and applied aluminium powder, which is used by crime scene investigators, with special brushes in order to make their print visible. They then used fingerprint tape to recover these prints and placed them on to acetate backing so they could examine them under the microscope.

The girls loved being Forensic Toxicologists for the morning and applying the science they had learnt. They really began to appreciate the work that is done at crime scenes and the level of detail required to match a set of fingerprints.

Mrs Gill-Lang, Chemistry Teacher