What percentage of fingerprint residue is typically made up of fats and oils?

The composition of fingerprint residue is primarily made up of a mixture of substances, including fats and oils, which play a crucial role in the identification process. Typically, fingerprint residue consists of about 3% fats and oils. This small percentage is significant because it contributes to the unique characteristics of each person's fingerprints. The primary components of fingerprint residue include water, salts, and proteins, alongside the fats and oils.

The presence of fats and oils in the residue helps create a clear print when placed on surfaces, as these lipids interact with various surfaces differently, aiding in detection and analysis during forensic investigations. Understanding the composition of fingerprint residue is vital for forensic scientists when developing effective methods for lifting and analyzing prints at crime scenes.