The list of drugs Hong Kong’s government considers dangerous is long and tough penalties reflect its no-nonsense policy. An effort to add CBD, an extract from the cannabis and hemp plants, to the list is therefore to be expected. But a flourishing industry has grown around the substance, with it being added to a range of products and promoted as helping relieve certain conditions. Despite the impact on vested companies of an outright ban, the lack of research into the potential risks and benefits requires erring on the side of caution.

CBD, also known as cannabidiol, can be found in an increasing number of imported products from cosmetics to candies to food and drinks. Marketers make all manner of claims, variously contending it can improve sleep and alleviate anxiety, chronic pain and depression. Its growing prevalence and endorsement by overseas celebrities has created a global multibillion-dollar industry that has been spurred by the rising acceptance of marijuana by governments in some parts of the world. But while it is an extract of cannabis and hemp, it is not believed to have the same psychotropic properties of another active compound in the plants, tetrahydrocannabinol, or THC.

Therein lies the problem. Research into CBD is rudimentary and its impact on health and potential benefits have not been extensively studied. In the United States, where 19 of the 50 states have legalised recreational marijuana, only one CBD product has been approved by federal health authorities, a prescription medication used to treat seizure disorders. As is often the case with a new industry, science and law lag availability and marketing. Until randomised, placebo-controlled, clinical trials are carried out, the claimed benefits are only a hypothesis.

The mainland, which for historic reasons has an even tougher approach towards drugs than Hong Kong, has already banned CBD. That has ironically helped spur the market in the city, with it being targeted by Chinese manufacturers and mainland buyers. The growing availability has sparked the concern of local authorities; in about one-third of items tested since 2019, more than 4,100, have contained TCH. A belief that separating CBD and TCH during the extraction process is imprecise and that there are bound to be traces of the latter in undetectable quantities is in part the reason for the call by security officials for a ban to be implemented this year. They also contend that it is a simple process to convert CBD to TCH.