Qualitative analysis is very important in forensic science because it helps identify unknown substances found at crime scenes. Here’s how it is used:
- Drug Identification:
- Detects illegal drugs or controlled substances in blood, urine, or other samples.
- Helps determine the type of drug present (e.g., cocaine, opiates, or methamphetamine).
- Toxicology:
- Identifies poisons, heavy metals, or toxins in tissues, blood, or stomach contents.
- For example, detecting arsenic, cyanide, or lead in a suspected poisoning case.
- Explosives and Gunshot Residues:
- Identifies chemicals from explosives or residues left after firing a gun.
- Helps trace the origin of explosives or confirm firearm use.
- Fibers, Paint, and Ink Analysis:
- Determines the composition of fibers, paints, or inks found at a crime scene.
- Helps link suspects to objects or locations.
- Blood and Bodily Fluids:
- Identifies the presence of blood, semen, or saliva using chemical tests.
- Can help confirm whether a sample is human or animal in origin.
- Trace Evidence:
- Detects small amounts of substances such as soil, glass, or residues.
- Provides clues about the environment or actions of a suspect.
In short:
Qualitative analysis in forensic science reveals what substances are present at a crime scene, helping investigators establish evidence, identify suspects, and understand events related to a crime. It is often the first step before quantitative tests determine amounts or concentrations.