While many people are troubled by hair loss and baldness, some people take the initiative to shave a "Mediterranean" hairstyle and wear a wig.
You read that right, here's it:
(Source: Shouxian Narcotics Control Commission)
And here's it:
(Source: Qianjiang Evening News)
And something like this:
(Source: City Express)
Even stranger, a woman shaved her hair and all the body hair all over her body.
(Source: Guangdong Anti-Narcotics)
What is the purpose of their actions? Why can't you get along with good hair?
It turned out that they were trying to evade a police examination - hair test!
(Source: Haidian POLICE Emoji)
But the final outcome is the same: Skynet is restored without leakage!
Let's talk about the black technology of "hair detection".
How does it make the "addict" appear, even shaved hair and wearing a wig can not be fooled?
After drugs enter the human body, they will appear in urine, blood, saliva and hair with the metabolism of the human body, and become evidence of drug abuse violations.
However, urinary tests, blood tests, etc. can be traced back to drug use for a very limited time.
A negative blood test can only mean that the person has not taken drugs within 24 hours.
A negative urine test can only indicate that there is no drug use within 3 days.
Once the time limit is exceeded, the drug component will not be detected in the blood and urine.
In the past, the police risked all kinds of dangers to catch drug dealers and drug addicts, but it often happened that because of the negative blood test and urine test, they could not provide evidence that the person had used drugs.
Some community drug rehabilitation personnel will stop taking drugs a few days in advance before the daily urine test, and even accelerate the discharge of drugs by drinking more water, eating diuretics, etc., and then relapse after regular urine tests, which brings a lot of trouble to our anti-drug work.
Later, researchers found that after drugs enter the human body, they will enter the hair follicles with the blood circulation.
The drug and its metabolites are fixed by the keratin in the hair and remain stably in the hair, not altered by the use of shampoo or hair coloring!
(Poisons (drugs) in the metabolic process of hair.) Image source: Network)
Therefore, after the "addict" takes drugs, the drugs and their metabolites will migrate from one end of the hair root to the end of the hair as the hair grows, as a real-time record of drug use information.
When the hair carrying the drug use information grows out of the skin, the inspector can infer the person's drug history through a segmented test of the hair.
At present, the hair detection drug use technology takes only 3 to 30 minutes to find out whether the test subject has smoked or injected drugs in the 6 months before the test, and the accuracy rate is as high as 99%[1].
This technology can not only detect methamphetamine, morphine, monoacetylmorphine, ketamine, cocaine, ecstasy and other drugs, but also cover new psychotropic substances such as fentanyl, methadone, benzodiazepine, fluoroamine and so on.
In further studies, researchers can even trace the origin and origin of drugs by analyzing their metabolic component characteristics, providing reliable anti-drug clues.
Some media have compared hair testing to "1 hair can test poison" when publicizing, which is somewhat exaggerated.
In fact, we need to collect "a handful" of hairs, the total amount should not be less than 100 milligrams, about 100 or more.
(The amount of a handful of hair.) Image source: Network)
According to the requirements of the Ministry of Public Security's "Specification for the Detection of Hair Samples of Drug-Related Personnel", the collected hair should be divided into two parts, A and B, each serving is not less than 50 mg [1].
When collecting, more than 100 hairs in the occipital bone part of the back of the head (that is, the back of the head) should be cut off against the scalp, placed in a clean collection bag and sealed, and the information of the person being collected should be recorded truthfully.
You may think: hair test poison is so powerful, then dye a hair before the examination, or simply shave your head, no hair can not be detected?
Please dispel this idea as soon as possible! Black technology is not something that can be cracked casually!
(Source: Hangzhou Railway Public Security Department He Neng New Media Studio)
In addition to hair, hair from any part of the human body, such as chest hair, pubic hair, armpit hair, leg hair, etc., can be used as a sample for poison testing.
Of course, the growth and shedding of hair in different parts will vary to a certain extent, so the number and content of drugs detected using different parts of hair will also vary accordingly.
South Korean star Park You-cheon shaved his hair and body hair to avoid examination.
The South Korean police, who were desperately pursuing, searched the door and found the leg hair that Park Hadtian had shed before in his house, and tested the hair again.
The results showed "positive", confirming that he had taken drugs and that it was methamphetamine.
Therefore, even if you are cruel to yourself and shave the body hair on all parts of the body, the police still have a way to conduct drug testing.
Since shaving hair does not work, can hair dye escape detection?
Japanese actress Noriko Sakai did this "riot operation" - cutting her hair short, dyeing her hair frequently, and trying to evade drug testing.
However, because the composition between hair dye reagents and drugs and metabolites is completely different, the interference of hair dye reagents on hair tests is almost negligible.
In the end, Noriko Sakai was successfully detected by the Tokyo police for drug ingredients from her hair, and she herself was punished as she deserved.
Just as the so-called "smart is mistaken by smart", in the face of the black technology of hair testing, any trick that wants to evade detection can not hide from the police's fiery eyes, and a "cool" song is given to "addicts".
Finally, please be sure to raise awareness of drug prevention:
1. Do not accept drinks and snacks from strangers, especially bars, KTV and other places prone to drugs, and drinks that are out of sight should not be drunk.
2. Never have a first time! Refuse the temptation to taste a bite!
3. Don't make drug friends, don't stick to drugs. If you find someone taking drugs and selling drugs, don't be quiet, and privately call the police.
Review expert: Ou Xueling | Forensic Doctoral Supervisor, Chief Forensic Physician
*The content of this article is a popularization of health knowledge and cannot be used as a specific diagnosis and treatment recommendation, nor is it a substitute for face-to-face consultation by a practicing physician, for reference only.
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