What is Hair Testing?

Hair is made up of keratin, a strong structural protein that comprises three parts, the medulla, the cortex, and the cuticle. Beyond its anthropological and biological meaning, this biomaterial has the ability to store what passes through the body. That’s why the courts use hair testing as a way to remove a person from suspicion or connect certain suspects with criminal activity. Forensic toxicologists are the people responsible for the analyzing of hair for the courts.

Hair testing by a forensic toxicologist refers to the methods of assessing the different characteristics of hair so that a sample can either be compared to hair found at the crime scene, evaluated for the presence of drugs, or used for DNA fingerprinting. Chemical substances circulating in the blood stream at the time that the hair is growing become part of the hair, eventually leaving proof of drug exposure. This proof can be used by toxicologists to find drugs used in sexual assaults, too.

To date, most drug screening for court evidence has been done using urine samples, but it is often impossible to detect most drugs in urine after 48 to 72 hours have elapsed, since the drugs can be out of the body by then. Hair analysis is proven to solve these problems, providing an accurate, secure, and retrospective window of detection.