Preparation and Evaluation of Fish Scalederived Powder for Latent Fingerprint Visualization

One of the most commonly used techniques at the forensic crime scene investigation stage is powder dusting of latent fingerprint. The conventional fingerprint powders on the other hand: pose health risks, environmental issues, and they are of a high price. The research has focused on preparing a low-cost and a safe-to-handle fish scale-derived powder as an alternative, non-toxic powder for the visualization of latent fingerprint on non-porous surfaces. The fresh fish scales were obtained from the fish market. A chemical-free extraction method was then carried out which involves washing, sun drying for about 24-48 hours, heating at low temperature, grinding (using a mortar & pestle followed by a mixer grinder) and sifting of fish scales to achieve a fine homogeneous powder that can be stored in a sealed plastic container. Powder dusting of the latent fingerprint using the brush method was carried out on 5 non-porous surfaces (painted metal, ceramic, glass, stainless steel and plastic). There are 20 samples of fingerprint per surface were taken (total 100). The quality of the visualized fingerprint was assessed on a standard fingerprint grading scale of 0-5 and a statistical analysis was performed on their respective mean values using SPSS (Version 20). A Forensic Utility Rate of 90% was obtained and 4.70 on stainless steel, 4.35 on plastic, 4.15 on glass, 3.70 on ceramic and 2.75 on painted metal surface respectively with a mean of 3.93 on all the surfaces. The findings confirm that fishery biowaste can serve as a functional latent fingerprint powder through a simple, accessible preparation protocol, contributing to the field of green forensic science.