Forensic toxicology focuses on the medical-legal aspects of chemical exposure and toxic injury. It involves analyzing samples like urine, blood, hair, oral fluid, and other bodily tissues or fluids to detect and quantify the presence of toxins and drugs. The concentration and type of substance present can provide information about factors like dosage and timing of exposure. A variety of analytical techniques are used, including chromatography methods and mass spectrometry, to screen for and confirm the identity of substances in biological samples as part of a forensic investigation.