JYJ Yuchun, "Hair Removal" and "staining" of Hot Topic in Korea.

Investigators typically perform "urine tests" and "hair tests" as evidence of narcotic use.

● Urinalysis: Drop urine in the test kit to check for drug reactions. It is said that there is less scope for human rights violations than hair testing, but the scope of determination of duration of use is narrow. The traces usually disappear in about a week. Yuchun conducted a urine test as a simple test on the 16th of the house search, and the drug reaction was "negative".

● Body hair and hair inspection: The discrimination period is longer than urine inspection. It can be determined from several months ago to one year ago drug use. Not only discrimination but also the frequency of drug use can be grasped. However, hair removal and staining often make it impossible to detect components.

● Leg Hair and chest hair that are not "hair removed" and "stained" are thin and short, so drug detection is often not easy.

● There may also be an eyebrow inspection. According to the recent results of the Korean police, the National Institute of Forensic Investigation researched the 200 eyebrows of narcotic suspects who had hair removal and hair staining of the entire body, and the result of "Methamphetamine POSITIVE" appeared and was prosecuted.