Drug analyzer helps neutralize illicit trade

Unlike the twisted drug maker in the popular US television series Breaking Bad－Chen Yuemeng uses his knowledge of chemistry to solve crimes.

Chen, 43, works for the Guiyang Public Security Bureau in Guizhou province. Since he started drug analysis work in 2010, he has handled more than 30,000 drug cases, examined more than 40,000 samples and is confident he has not made a single mistake.

He works in the laboratory and occasionally goes to crime scenes to gather samples. However, he always reminds himself to be cautious as every examination of drug-related evidence is crucial to the outcome of a case and influences the sentence a convicted criminal receives.

On the job

After graduating from Guizhou University's chemistry school in 2001, Chen worked for a company in Guiyang for five years. In 2007, he became a police officer at the city's public security bureau and worked in its drug investigation unit for three years.

He recalled a drug raid in 2009 when the intelligence differed from the situation on the ground. He approached the target room cautiously but was forced to draw his gun and shout "don't move!" when he encountered several drug dealers. After subduing the dealers, he immediately called his colleagues for backup.

Chen transferred to the technical division with the bureau's drug identification center in 2010. There were only two people in the division at that time, and Chen's co-worker later applied for a transfer over health concerns about the chemicals used in their work.

However, over the years more technical personnel have been hired and the team now has 12 members. "I've stuck with the job because I like it," Chen said. "I like the feeling of working in the lab surrounded by the apparatus, reagents and glassware, and I can use my knowledge to solve cases."

Chen handles about 3,000 cases every year and analyzes more than 4,000 suspected drug samples.

Sometimes it's just as important for the forensics team to establish that what has been seized is not illicit drugs.

Chen once received samples of what police believed was ketamine seized in a drug operation. He and his colleagues used five different methods to analyze the sample but could not detect any illegal drugs.

The sample was later sent to the Ministry of Public Security for further testing and found to be sugar.

"Officers at the scene should consider the seizure as suspect drugs, but a conclusion can only be drawn after that seizure has been examined," he said. "Every forensic report determines the nature of the case. Detection personnel must have both professional skills and a high sense of responsibility."

Technical challenges

Police drug examination procedures usually involve grinding, weighing and dissolving the seized materials and using forensic equipment－such as mass and infrared spectrometers－for final analysis before a report is issued. The procedure can sometimes be as quick as an hour, which speeds up the processing of cases, Chen said.

In 2019, Chen and his colleagues further developed near-infrared spectroscopy analysis－a method used by police departments around the world－to examine drugs.

Examiners can get information about a sample's organic molecules by scanning the near-infrared spectrum, shortening the time it takes to identify drugs such as methamphetamine, heroin and ketamine, to around five minutes. When trying to determine whether a suspect has used drugs, urine, saliva, blood or hair samples are usually required.

However, the nature of some drugs can present tougher challenges for proper identification. Identifying cannabis on a suspect is a challenge for inspectors. The main psychoactive ingredient of cannabis, tetrahydrocannabinol, has a low rate of binding to melanin in the hair and easily degrades after prolonged exposure to light.

Synthetic drugs

Identifying new synthetic laboratory drugs is another obstacle. While their long-term use can cause mental and physical problems, they are difficult to identify because of the wide varieties produced and their complex chemical structures, Chen said.

By the end of 2019, China had about 2.14 million drug users, down 10.6 percent year-on-year, according to a report released by Office of China Narcotics Control Commission in June. It said new forms and types of drugs are emerging, making identification of them more difficult. Some drugs were even disguised as milk tea and chocolate.

"The biggest challenge is helping drug users to control their temptations and stop them taking drugs," Chen said. "Even people who have been off them for a long time may return to drugs if they can't control themselves."

Police in Guiyang regularly examine the urine samples of recovered drug addicts to ensure they aren't using alternative substances. Since 2018, Guiyang's sewage has been routinely tested for the concentration of drugs.

Family life

Although Chen has achieved a lot in his work, he regrets not spending more time with his family and also the fact he cannot talk about his job with them.

He usually arrives at the office before 8 am and leaves around 6 am. It is common for he and his colleagues to work to 2 am, or wait until the next day for samples of suspect drugs that need to be tested.

"Some tasks are unexpected and we have to be ready all the time to offer support, so it is hard for me to balance work and home life," he said. "My wife occasionally complains that I often ignore the family and only care about work. But she understands me well and often worries about my health."

Chen has two children, ages 2 and 11, who he said aren't fully aware of what his job entails. "My older kid once saw a report about me on the TV, and he was quite proud of that and showed it to his classmates," he said.

Wang Jin contributed to this story.