WS-23 vs natural menthol in UK vape liquids (2026): a safety and flavour comparison for shoppers and regulators

Introduction

Cooling agents have become an integral part of modern e-liquids. Two of the most discussed options in 2026 are natural menthol (the classic minty compound) and the synthetic coolant WS-23 (chemical name: 2-Isopropyl-N,2,3-trimethylbutyramide). WS-23 delivers a pronounced "ice" sensation without adding a minty flavour, and its use has expanded rapidly across fruit, candy and menthol-style vapes. This article compares WS-23 and natural menthol on flavour, consumer experience, prevalence and safety evidence — with practical recommendations for both shoppers and regulators.

Feature-by-feature comparison

1. Chemistry and sensory effect

WS-23 is a synthetic amide-based cooling agent. It activates cold receptors to give a strong cooling sensation while remaining virtually flavourless, so it preserves the base liquid's fruit or candy notes. By contrast, natural menthol is a terpene-like compound that combines cooling with a distinct minty aroma and taste.

2. Flavour profile and applications

• WS-23: Favoured where manufacturers want a sharp ‘ice’ or ‘cool’ effect without altering the chosen flavour. This is why synthetic coolants now appear in non-menthol fruit and sweet liquids as well as menthol blends.
• Natural menthol: Used where a mint character is desirable — classic menthol vapes and blends that rely on mint as part of the flavour profile.

3. Prevalence and marketing

Independent testing has shown WS-series compounds are widespread: WS-3 was detected in 24 of 25 refill e-liquids sampled, and WS-23 turned up in nearly all (13 of 14) Puffbar disposable flavours examined in a particular survey. In the UK, WS-series chemistry traces back to Wilkinson Sword (hence the 'WS' name), and suppliers and retailers openly market WS-23 as an additive — making it easy for DIYers and commercial brands to include it.

4. User experience and acceptability

Multiple user-experience studies and lab evaluations report that WS-23 tends to increase perceived smoothness, perceived coolness and willingness-to-reuse compared with uncooled liquids. Many vapers rate WS-23 blends as smoother and less harsh than menthol at comparable cooling intensity.

5. Safety data and toxicology indicators

Safety debate is central. Risk-modelling work has reported margin-of-exposure (MOE) values below conventional safety thresholds (MOE <100) for many products containing WS-series coolants. In a notable assessment, MOEs for WS-23 were under 100 for 11 of 13 Puffbar products across typical vaping scenarios — a finding that prompted calls for regulatory review. Public-health commentators and researchers have highlighted gaps in inhalation-toxicity data and raised concerns about potential long-term pulmonary or systemic effects from regular exposure to synthetic coolants.

6. Labelling and consumer transparency

Because WS-23 is often described as a neutral 'cooling agent', it may be included without obvious 'menthol' labelling; consequently consumers can be exposed even if they specifically avoid menthol-labelled liquids. This is an important practical difference for shoppers and for policy-makers focused on labelling transparency.

Pros and cons

WS-23 (synthetic cooling agent)

• Pros: Strong cooling without mint flavour; enhances fruit/candy liquids; perceived smoothness and reduced harshness; easy to dose for consistent effect.
• Cons: Widespread presence even in non-menthol products; inhalation toxicology data limited; MOE analyses have flagged exposures below safety margins for many products; regulatory scrutiny increasing.

Natural menthol

• Pros: Long history of use; identifiable flavour so consumers know what they’re choosing; more established toxicological literature for menthol itself (though not without questions).
• Cons: Adds a minty flavour that not all users want; may be perceived as harsher than synthetic coolants in some formulations; still subject to regulatory limits in some jurisdictions.

Practical recommendations

For shoppers

If you want a strong cooling sensation without mint: WS-23 formulations deliver that effect, but be cautious. Consider lower-strength products and favour reputable brands that disclose ingredients and concentrations. If you prefer transparency or want to avoid synthetic additives, choose clearly labelled menthol liquids — for example, Vape Emporium stocks menthol and ice shortfills such as Big Bold Menthol Series 100ml and ice options like Fantasi Ice 100ml or Fantasi Ice Remix 100ml if you want to sample different cooling styles without hidden additives.

If you prefer fruity or candy flavours but want a cooling touch, check product labels and descriptions carefully — some non-menthol liquids may contain WS-23 or related coolants. For those seeking a milder ice effect or concerned about synthetic additives, consider products that explicitly state they use natural menthol or no added coolants.

For regulators and policy-makers

Evidence of frequent WS-23 use and MOEs below conventional safety thresholds for many products suggests a need for focused review. Recommended actions include tighter labelling rules (disclosure of cooling agents and concentrations), standardised inhalation toxicology testing for WS-series compounds, and exposure-based risk assessments that reflect realistic vaping behaviours. Because synthetic coolants are being added to products not labelled as 'menthol', targeted surveillance of non-menthol flavours is also important.

Conclusion

WS-23 and natural menthol offer distinct trade-offs. WS-23 excels at delivering intense cooling without mint flavour and is popular with manufacturers and many users for that reason; however, its widespread, often undisclosed use and emerging MOE concerns mean shoppers and regulators should treat it with caution. Natural menthol gives a recognisable flavour profile and a longer usage history but may not suit vapers who want a neutral-cooling effect.

For consumers: choose products from transparent brands, check labels, and consider lower-strength options if you’re concerned about inhalation exposures. For regulators: prioritise inhalation safety testing, labelling transparency and continued monitoring. Both groups will benefit from more robust, long-term data on inhalation effects of synthetic cooling agents before wholesale acceptance becomes the norm.

Note: This article summarises public testing and research findings available up to 2026 and is intended to inform shoppers and policy-makers rather than provide medical advice.

Further reading and product exploration: for menthol/ice e-liquids available at Vape Emporium, see options such as Dr Vapes Pink Frozen 100ml.