[Correspondence] The rise of nicotine analogues in vaping products

Synthetic nicotine analogues are a new class of compounds making their way into the European and US vaping markets, raising urgent questions about public health, regulation, and scientific research.1 At the centre of this issue is 6-methyl nicotine. 6-methyl nicotine has attracted growing attention as a synthetic derivative that is promoted as an alternative to nicotine. The emergence of 6-methyl nicotine is no coincidence, but rather a direct consequence of the regulatory efforts targeting synthetic nicotine in the USA and Europe.