The Chinese police seize fentanyl substances in July, 2015 during the first case of fentanyl trafficking in the country. [Photo: customs.gov.cn]
China is to ban the use of carfentanil, which is usually used as a tranquilizer for elephants and other large animals, and three related opioids beginning next month.
The four psychoactive substances, namely carfentanil, Furan fentanyl, Acrylamide fentanyl and oxalyl fentanyl, are also known as lab drugs potent enough to prove fatal in small doses.
Deng Ming, a deputy director from China's anti-drug office, said among the four drugs, carfentail is particularly potent.
"Carfentanil is a typical fentanyl substance and capable of medicating pain. It is 1,000 times more potent than morphine, and two milligrams of it can kill an adult. It's more powerful than other fentanyl varieties," said Deng.
Carfentanil has also been used as a chemical weapon and described as a potential substance used in terrorist attacks.
The US has accused China of being the top source of fentanyl in North America, but the US Drug Enforcement Administration called the upcoming restriction a potential "game-changer" that is likely to reduce supply of key chemicals behind a surge of overdoses and deaths among unsuspecting drug users.
Domestically, fentanyl abuse has only been discovered on a relatively small scale in China, with 22 reported police seizures of the substance in Yunnan, Hubei and Liaoning Provinces throughout 2016.
Police authorities say people dealing the new psychoactive substances are usually professionals with medical, chemical and even international legal knowledge regarding them, which makes it difficult to combat drug trafficking.
To tackle the challenge, the anti-drug office said it will establish a national standard substance bank to collect information and help people identify new psychoactive substances.
To date, China has restricted the use of 134 psychoactive substances.