Current Perspectives in the Forensic Analysis of Timbers using Vibrational Spectroscopy: A Review

Abstract

Wildlife crime has increased significantly with respect to timbers such as illegal timber trading, logging, harvesting, and counterfeiting. It has tremendously drained the economy of different countries since timber trafficking at the global level has an average annual net worth of US$ 50-150 billion. Moreover, timbers can act as important forensic evidence as they can be found at the crime scenes revealing the relationships between the crime scene and corpus delicti. Since ancient times, various traditional techniques have been used for timber identification such as anatomical investigation by visual method at the macroscopic and microscopic levels. However, morphological and anatomical techniques have some advantages, such as cost effectiveness, and limitations as they require experienced personnel. Vibrational spectroscopic tools such as infrared and Raman spectroscopy help in discriminating various species of timber as different timber species have unique phytochemicals. By examining the concentrations of cellulose, lignin, and hemicelluloses, the chemical composition can also be estimated. Herein, this review is carried out using vibrational spectroscopic methods for timber identification to combat criminal activities related to timbers for the dissemination of justice. Recent advancements and prospects are also emphasized in this review paper.