A verdict here starts with a label, because for most buyers it is the only ingredient disclosure there is. A South Korean test batch puts a number on what that document is worth.

The country’s Ministry of Food and Drug Safety examined 105 vaping products sold as nicotine-free and reported nicotine in 13 of them and 6-methyl nicotine in 12, as reported by Tobacco Reporter on 4 August. The report does not say whether any product held both, so the number failing its own label sits between 13 and 25 out of 105 — either way, a shelf whose whole proposition is the absence of the thing found inside it.

The analogue is the interesting half

Thirteen products carrying undeclared nicotine is a familiar sort of failure. The twelve carrying 6-methyl nicotine are a structural one. The compound is not nicotine, so a rule drafted around the word can miss it, and a bottle can be truthful about nicotine while telling a buyer almost nothing. Industry figures quoted in the same report describe goods that sidestep tobacco rules while trading on a nicotine-free claim.

Duke and Yale researchers, senior author Sven Eric Jordt, reported in 2024 that analogue products are unreliable on their own terms too: a Spree Bar declaring 5 percent 6-methyl nicotine measured roughly 88 percent below label. That work also cited rodent experiments describing the compound as far more potent than nicotine at the brain’s receptors.

The timing is not accidental. The same report says synthetic nicotine came under South Korea’s tobacco rules and higher taxes in April, and that imports declared nicotine-free rose from 95 tons in 2022 to 164 tons in 2025, most sourced from China. A category defined by what it does not contain is a convenient place to stand when the definition next door has just tightened. Toxicity assessments and investigations into unlicensed sellers are described as under way.

What it does to a tasting note

For a desk that reads a bottle before judging it, this is the uncomfortable part. If a declared nicotine content — the one number on the panel with a legal consequence attached — can be wrong on this many products at once, the softer declarations carry less weight still. The PG/VG split, the sweetener position, the flavour percentages, the batch code: nobody is checking any of them.

That is not an argument that every bottle lies: at least 80 of the 105 turned up neither compound. It is an argument for reading an unverified spec sheet as a claim, not a fact — the same way the nicotine cocrystal filing reads, as a proposal on paper until someone independent measures it.

The compound at the centre of this, declared or not, is nicotine: an addictive chemical, sold to adults of legal purchase age — 21 or over in the United States, 18 or over in most other markets — and to nobody else.