ASEAN drug markets continue to be inundated with methamphetamine, while as-yet legally unclassified psychoactive substances are on the rise, attendees at a regional UN conference in Vientiane heard yesterday.

Regional seizures of crystal methamphetamine are up fivefold from what they were just a half decade ago, and the purity of some confiscated batches has been “alarmingly” high, according to conference organiser the UN Office on Drugs and Crime (UNODC).

However, head of the Cambodian National Authority for Combating Drugs (NACD) Meas Vyrith said yesterday that while regional purity may be up, in Cambodia, meth quality peaked last year and is now on a downward trajectory as dealers adulterate their product with ever more cutting agents.

He attributed this in part to the destruction of what he believes to have been the last of Cambodia’s large-scale meth labs in 2012 and the NACD’s training of law enforcement and border officials to recognise precursor chemicals used in the production of synthetic drugs like meth.

Also on the agenda at yesterday’s conference – which continues this morning – were so-called new psychoactive substances (NPSs), previously unseen drugs that have not yet been covered by countries’ drug legislation, which the UNODC says have seen an increase in trafficking and production.

Vyrith said NPSs had yet to reach Cambodia, but that the Kingdom’s drug police had already begun preparations for the arrival of kratom, a herbal narcotic that he said can be smoked or drank as a tea and puts users in a euphoric, hallucinatory state.