The potential environmental and health risks posed by the inappropriate disposal of RRPs are undeniable and, if not addressed, risk being weaponised by THR opponents who have, up to now, based their arguments on largely questionable science.

Declines in RLX and Smoore highlight the importance of rigorous regulatory risk assessment. Governments' desire to protect revenue and the abstinence-based approach of the WHO suggests growing regulatory pressure. Still, investors remain positive.

RLX, now valued at $38bn, confirms investor appetite for THR and should entice entrepreneurs to raise capital to accelerate product development. High valuations and the rising threat of disruption likely also accelerate tobacco industry transformation.

Smoore's listing should provide a substantial incentive for investment in reduced-risk nicotine products. It highlights a multi-billion opportunity for entrepreneurs, but also serves to remind the tobacco industry of the need to "get THR right".

Australia's attempt to ban imports of nicotine-based vaping products highlights real obstacles to tobacco harm reduction.