Answer 1: A gun shot residue is the powdery discharge that release after the firing process of the firearm. The powdery discharge consists of unburnt or partially burnt primer, propellants, fragments of the projectiles, cartilage cases and residues present inside the firearm.
It is important for the forensic scientists so as to detect the culprit as these residues are left on the clothes and hands after firing. It can be used to identify the direction and distance of firing.
Answer 2: The complications associated with gunshot residue are:
1. The particles are very small and may exhibit low density they are likely to blow by wind so they may not be found at some crime scene.
2. As the powdery discharge consists of explosive particles in small amounts but on testing can explode and can cause harm.