China is adding all nitazenes, along with 12 other new psychoactive substances, to its controlled drug list in its latest move to address the growing challenge of emerging synthetic drugs.

Nitazenes are powerful synthetic opioids that have recently gained a foothold in the illicit drug market. Compared with traditional opioids, nitazenes are more likely to cause severe respiratory depression, making them particularly dangerous.

The new regulation, announced on Thursday by the Office of China National Narcotics Control Commission, will take effect on July 1.

In July last year, China placed 46 new psychoactive substances — including certain nitazenes — under regulation.

Shan Yehua, deputy director of the office, said the decision to schedule all nitazenes follows the detection of new substitute compounds being abused despite existing controls.

She said the move reflects China's ongoing innovation in drug control, following its blanket regulation of all fentanyl-related substances in 2019 and all synthetic cannabinoids in 2021.

It also marks part of China's broader response to the increasingly prominent abuse of unregulated substances, Shan said, noting that the country is monitoring substance abuse through its antidrug laboratories.

"The control of new psychoactive substances is a difficult issue for all countries in the world. It can hardly be solved by only one country," she said.

China has adopted tough counternarcotics measures and explored more effective approaches, such as scheduling entire classes of substances and acting quickly to add new ones to its controlled list.

"We stand ready to contribute China's solutions and China's wisdom to addressing the challenge," Shan said.

At the request of the United States, China regulated all fentanyl-related substances in 2019, becoming the first country in the world to do so. Since the ban, China has not detected criminal cases of smuggling or selling the substances abroad.

However, the US imposed additional tariffs on Chinese goods twice this year, citing fentanyl as the reason — a move described by Chinese officials as "typical bullying".

"This has undermined the two countries' trust and basis for dialogue in the counternarcotics field," said Wei Xiaojun, head of the Ministry of Public Security's narcotics control bureau.

Wei said China, which has some of the world's strictest antidrug policies, has kept the percentage of drug abusers to less than 0.06 percent of its population of more than 1.4 billion. As a major chemical producer, China also does not face a fentanyl abuse problem, he said.

In contrast, more than 10 percent of the over 300 million people in the US are drug abusers, he said.

"Ultimately, this is a result of the governance deficiency of the US government," Wei said, urging Washington to reflect on itself and take more effective action to reduce demand for illicit drugs.

"We hope the US will respect China's efforts, face the truth and correct its wrongdoing as soon as possible," he said.