What Is WS-23 In Vape E Liquid?

WS-23 is a man made cooling agent added to some vape e liquids to create an icy, menthol like sensation on the tongue and throat without adding a minty taste. Its full chemical name is methyl diisopropyl propionamide. Flavour houses use it in small amounts inside all sorts of flavours, from fruit to dessert to tobacco. WS-23 is a flavouring ingredient, not a nicotine strength. That is all it does.

We get asked about this one a lot. Usually from someone staring at an ingredient list, wondering why a mango or a bubblegum pod suddenly hits icy cold on the exhale. It is a fair question, and the honest answer takes a bit of chemistry and a bit of UK rule book. Below we go through what WS-23 actually is, how it compares with menthol, where it shows up in prefilled pods and nic salt e liquids, and what the research does and does not say about it so far.

WS-23 Flavouring Explained, What Methyl Diisopropyl Propionamide Means

Methyl diisopropyl propionamide is the proper chemical name behind the trade name WS-23. Most people never use it. It belongs to a small family of synthetic compounds developed originally for the food and fragrance industry, built to switch on the body's own cold sensing system without using menthol itself. The "WS" in WS-23 is simply a reference code used across this family of cooling compounds, in the same way paracetamol has a longer chemical name that most people never use either.

Flavour houses supply WS-23 to e liquid manufacturers as a concentrated additive, measured in tiny percentages, usually well under one percent of the total mix. It sits alongside everything else already in the bottle. It never replaces the propylene glycol and vegetable glycerine base, and it never replaces the nicotine salt either. On an ingredient list it may appear by its own name, by a trade name a particular supplier uses, or grouped under a general flavouring description, which we cover later in this piece.

It helps to be precise here. The word "menthol" and the word "cooling" get used almost interchangeably by vapers, when they are not the same thing at all. Menthol is a natural compound extracted from mint plants, with its own distinct minty taste as well as its cooling effect. WS-23 is a different molecule entirely, built in a laboratory, and it was specifically designed to strip the taste away from the cooling sensation.

The propylene glycol and vegetable glycerine base that carries every e liquid flavour also plays a small part in how a cooling agent feels in practice. A higher vegetable glycerine mix tends to carry flavour and sensation a little more slowly across the palate. So a WS-23 finish in a thicker, glycerine heavy nic salt can feel like it builds for a second after the exhale, rather than arriving instantly. None of that changes what WS-23 itself is doing chemically, it simply affects how quickly you notice it.

 

How WS-23 Creates A Cooling Sensation Without Menthol's Taste

The cooling feeling from both menthol and WS-23 comes from the same place in the body, a receptor called TRPM8. Think of TRPM8 as a temperature sensor. It sits in nerve endings across the mouth and throat, the same sensor that fires when cold water touches your lips or a gust of winter air hits your face. Both menthol and WS-23 switch this receptor on chemically, tricking the nerve into reporting cold even though nothing has actually dropped in temperature.

That is the mechanism in short. Cold without actual cold.

Where the two compounds part ways is in what else they do once they arrive. Menthol's structure also happens to taste minty on its own. So whenever menthol turns up in anything you vape or eat, you get the cooling sensation and the mint flavour bundled together, whether you want both or not. WS-23 activates that same TRPM8 pathway but, because its shape is different, it does not carry that mint taste along with it.

That is the whole reason flavour developers reach for it. A fruit flavour built with menthol ends up tasting like fruit and mint together, which is a particular taste some vapers love and others actively avoid. The same fruit flavour built with WS-23 instead can keep its true fruit character on the tongue while still finishing with a cold, almost icy rush on the exhale. The flavour stays where it should, and the cooling arrives as a separate sensation layered on top.

This is also the direct answer to why some vapes taste icy without menthol anywhere on the label. The label rarely says so outright. If an e liquid lists WS-23, or a general cooling or icy flavouring, rather than menthol, that icy hit you feel is almost certainly coming from this synthetic compound rather than from any mint extract at all.

There is also a difference in how the two sensations reach you. Flavour chemists sometimes describe this as the taste pathway and the trigeminal pathway working separately. Your tongue reads sweetness and the fruit or dessert notes through ordinary taste receptors. The cold sensation from WS-23 or menthol travels through a different set of nerve endings entirely, ones that respond to temperature and irritation rather than flavour. Because WS-23 barely touches the taste pathway, the fruit or dessert flavour stays clean, while the cold sensation runs alongside it as its own separate signal.

WS-23 Vs Menthol In Prefilled Pods And Nic Salt E Liquids

This is where it gets practical.

Once you know what each compound actually does, choosing between a WS-23 pod and a menthol pod becomes a question of what flavour experience you actually want, rather than which one is stronger or which one is somehow more vape like. Both are legitimate, widely used flavouring choices across prefilled pods and nic salt e liquids sold in the UK, and neither one says anything about the nicotine strength inside the pod.

That table is a rough guide, not a fixed rule. Individual e liquids blend ratios differently. Even so, it reflects the pattern most WS-23 and menthol flavours follow.

Fruit And Dessert Flavours With A WS-23 Ice Finish

WS-23 turns up most often in fruit and dessert style e liquids that want a cold edge without becoming a mint flavour. A watermelon ice pod or a mango and passion fruit ice pod is usually built this way. The fruit concentrate does the work of delivering the actual taste. Strawberry, melon, citrus, whatever the flavour profile calls for. The WS-23 sits underneath it, delivering that cold rush on the exhale that gives the flavour its "ice" name.

Done well, the effect is genuinely pleasant rather than overpowering. The fruit arrives first on the inhale, then a clean, almost refreshing chill follows through on the exhale, without a hint of mintiness muddying the fruit character. Done badly, with too much WS-23 in the mix, the cooling can tip into a mild numbing feeling on the tongue and throat instead. That is one reason makers keep the amount low and test the balance carefully before a flavour goes into production.

Classic Menthol Pods And Their Own Flavour Profile

Menthol flavoured pods sit in a different lane entirely. The mint taste is the point here, not a side effect to be managed. Vapers who choose menthol tend to want that traditional, slightly medicinal, cooling mint character that has been part of tobacco and vaping products for decades. A menthol pod will usually carry a more pronounced minty note on both the inhale and the exhale, rather than the cold arriving mainly on the finish.

Some e liquids actually combine the two, using a smaller amount of real menthol for its taste alongside a touch of WS-23 to boost the overall chill without needing a heavier dose of menthol itself. This is a common approach across the flavour industry, not something unique to any one brand. It is one more reason an ingredient list is worth a proper read, rather than a glance at the flavour name on the front of the box.

Synthetic Cooling Agent Vape Ingredients, Where WS-23 Appears On The Label

WS-23 is one of a small group of synthetic cooling agents used across the flavour industry, alongside close relatives such as WS-3 and WS-5. Each one is built around the same basic idea, activating TRPM8 without a strong taste of its own. These compounds did not start life in vaping. They were developed for use in chewing gum and toothpaste, and in various confectionery lines, where food safety authorities had already assessed them for that kind of use. Flavour houses only began supplying them to the e liquid industry later.

In e liquids, a synthetic cooling agent like WS-23 almost never appears as the headline ingredient. It sits in the background of the flavour description, which tends to focus on the fruit or dessert name the vaper actually chose the product for. Where it is listed by name at all, it usually appears in a full ingredient declaration rather than on the front of the packaging. The rules that matter here are about what manufacturers tell regulators and retailers, not necessarily what appears in large print on the box.

Reading A WS-23 Flavouring E Liquid Ingredient List

If you want to check whether a particular pod or bottle uses WS-23, the ingredient list is the place to look, not the flavour name on the front. Read the small print. Look for "WS-23," "methyl diisopropyl propionamide," or a cooling or icy flavouring description. Some manufacturers name it directly. Others describe it only as part of a wider flavouring blend. UK ingredient guidance allows minor flavouring parts, present below a very small threshold, to be grouped under one general term rather than listed one by one, as long as the supplier has confirmed what is in the mix.

None of this changes what the ingredient does. Whether it is named on its own or folded into a general flavouring description, WS-23 is doing the same job, adding a cold sensation to the vape without altering the core flavour character. If a cooling or icy finish matters to you, the safest approach is simply to try a product described as "ice" and judge it by the sensation on your own palate. Wording on packaging varies between brands far more than the chemistry does.

It is worth saying plainly that an ingredient appearing under a general flavouring description rather than by its own chemical name is not a sign of anything being hidden or done wrong. The notification happens behind the scenes with the regulator, separately from what appears on a bottle or pod box. The rules on grouping minor flavouring parts exist so that packaging does not end up listing dozens of compounds in print nobody could actually read. If you genuinely want the detail, a quick message to the manufacturer or retailer asking whether a particular flavour uses WS-23 is a fair question, and a compliant business should be able to answer it.

Is WS-23 Safe To Vape? What The Research Says So Far

This is the question that matters most.

This is the question we think deserves the most careful, honest answer on this whole page. We are going to resist the urge to give you a tidy yes or no. Neither one would be true to what the research actually shows. WS-23 and its relatives were originally approved for food and oral care use, where they have a long track record at the low levels used in those products. Inhaling a flavouring compound through a vape is a different exposure route entirely. That is the part where the science is still catching up.

Some research bodies and trade publications have noted that synthetic cooling agents in vaping products are not yet thoroughly studied for inhaled use. A handful of academic studies have also found these compounds at levels, in some products, that run higher than menthol is typically used at in traditional menthol flavoured items. A German food safety institute has made a similar point in its own published opinion, describing the evidence base on synthetic coolants in e-cigarettes as still developing rather than settled.

One set of findings, presented by researchers including a team at Duke University, used exposure modelling rather than direct human health testing. The researchers measured how much WS-23 and a related cooling compound turned up in a batch of sampled e liquids and disposable products. They then compared those amounts against a margin of exposure. That is a toxicology tool. It checks a measured dose against the dose known to cause harm in animal studies, and it flags anything sitting too close to that line. Some of the sampled products fell inside the range the researchers considered worth flagging. That is a research method built on estimation, not a confirmed health outcome in a human vaper. The sampling was also carried out on products sold in the United States, not on the regulated UK market. It cannot be read across directly as a finding about UK stocked e liquids.

We are not going to tell you that WS-23 has been proven safe to inhale over the long term, because nobody has produced that evidence either way yet. We are equally not going to tell you it has been proven dangerous, because the published research so far is exposure estimation and laboratory receptor work, not a confirmed harm finding in vapers. That is the honest position. It is the one every responsible source on this topic currently takes, that research into inhaled synthetic cooling agents is described as limited and ongoing. If that changes, UK regulators have a process for reassessing ingredients, which we cover in the next section.

Is WS-23 A Nicotine Strength Or A Flavour

Short answer, a flavour.

WS-23 is a flavour ingredient only. It has no connection at all to nicotine strength. Adding it does not make an e liquid stronger, weaker, or more addictive in any way. A 10mg nic salt pod with WS-23 in the flavour mix delivers exactly 10mg of nicotine per millilitre, in the same way a 20mg pod delivers 20mg, no matter what the pod tastes of. If you are choosing a strength, choose it based on your own nicotine needs. Choose the flavour separately.

Does WS-23 Need To Be Declared On Vape Packaging? MHRA Notification Explained

Every nicotine containing e liquid sold legally in the UK, whatever flavour or cooling agent it uses, has to be notified to the Medicines and Healthcare products Regulatory Agency, the MHRA, before it goes on sale. This notification sits under the Tobacco and Related Products Regulations 2016, usually shortened to TRPR, which is the piece of law that sets out what manufacturers and importers must submit and what they must not exceed. You can read part 6 of the Tobacco and Related Products Regulations 2016 on legislation.gov.uk if you want to see the actual notification requirement in full.

Part of that notification is a complete ingredient list, along with toxicological data on each ingredient where it is required, submitted directly to the MHRA rather than printed in full on every pod box. Specific guidance on this is known as Chapter 6. It sets out that flavourings present below 0.1 percent of the total mix may sometimes be grouped under one general term on the submission, rather than named one by one. This only applies as long as the supplier has given written assurance of what is in the blend. A compound such as WS-23 is used at a small fraction of a percent. It can fall into exactly this category. That is one reason you will see it named outright on some ingredient lists, and only described in general terms on others. You can find the detail in the government's ingredient guidance for e-cigarette liquids.

We should be straightforward about something here rather than overstate it. No UK government source currently names or separately assesses WS-23 by name. No rule names it directly. There is no WS-23 specific notice, warning or approval from the MHRA, from Trading Standards, or from any other UK body. We are not going to pretend otherwise just to make this section sound more authoritative than it is. What exists instead is the general notification framework above, which every nicotine containing e liquid must pass through regardless of which flavouring compounds it contains, WS-23 included. That framework is the real, honest answer to whether WS-23 needs declaring, it gets captured by the same ingredient notification process every other flavouring component goes through, rather than by any rule written specifically about it.

Every range we stock at Prefilled Vapes Outlet is MHRA notified under the TRPR submission system. That covers cooling agents too. The full ingredient and toxicological information behind each flavour has already been submitted and reviewed through that process before the product reaches our shelves.

 

UK Nicotine Strength And Tank Capacity Rules For WS-23 Flavoured Pods

Whatever flavouring a pod uses, UK law sets the same hard limits around it. The limit still applies regardless. Pod and tank capacity cannot exceed 2ml, and nicotine strength cannot exceed 20mg per millilitre, full stop, with no exceptions for a particular flavour or cooling agent. These limits come from the same Tobacco and Related Products Regulations 2016 covered above. The government's regulations for e-cigarette consumer products set out the wider framework these limits sit inside, alongside packaging and advertising rules that apply right across the UK vaping market.

Every pod kit, prefilled pod and nic salt e liquid we sell sits inside those same limits, whether the flavour on the box reads mango ice, classic menthol, or plain tobacco. Packaging also has to carry a health warning covering 30 percent of the two largest surfaces, and every listing for a nicotine containing product states clearly that this product contains nicotine which is a highly addictive substance, as the law requires. Trading Standards enforces these rules at a local level across England, Scotland, Wales and Northern Ireland. It checks that retailers and manufacturers stay inside the capacity and strength limits, and that age verification is actually happening at the point of sale.

On that last point, every order on our site goes through age verification at checkout. No exceptions. Our entire range, cooling flavours and menthol flavours alike, is sold for adult smokers and vapers aged 18 and over only, and we will not sell to anyone who cannot confirm they meet that age, whatever flavour they are after.

It is also worth knowing that the UK Disposable Vape Ban took effect on 1 June 2025, which removed single use disposable vapes from sale across the country, regardless of which flavour or cooling agent they used. That ban has nothing to do with WS-23 itself. It is about battery type and device design, not flavouring. Our prefilled pod kits use a rechargeable battery with a replaceable pod. That design is what keeps a product legally on sale after the ban, whatever flavour sits inside the pod.

WS-23 Flavoured Nic Salts And Prefilled Pod Kits In Stock

If an icy fruit or dessert flavour with that WS-23 style finish sounds like what you are after, our full range lets you shop nicotine salt e liquids by flavour family and strength, so you can pick something that matches both the cooling character you want and the nicotine level that actually suits you. If you prefer your device already filled and ready to go, you can browse prefilled pod kits across our ice, fruit and classic ranges in one place.

Flavour trends move fairly quickly here. New icy and cooling variations turn up often as flavour houses refine their mixes. It is worth checking back to see the latest flavours in stock every so often, rather than assuming the range you saw last month is still the full picture. If you are still working out strengths, devices and flavour families before you commit to anything, that is worth sorting first. If you're new to vaping, start with our beginner's guide, which covers the basics in plain terms before you spend any money.

However you choose to flavour your vape, the strength decision and the flavour decision are genuinely separate choices. Treating them that way tends to get people to a pod they actually enjoy faster than picking purely on the name printed on the box. A simple way to test which cooling style actually suits you, without buying several full packs at once, is to pick one WS-23 style ice flavour and one classic menthol flavour in the same nicotine strength. Vape each for a day or two before deciding. The difference between the two is usually obvious within the first few puffs, since one carries a true mint taste throughout and the other keeps the fruit or dessert flavour clean with the cold arriving mainly on the exhale.

WS-23 Vape Juice Questions Answered

1. What is WS-23 in vape juice?
   WS-23 is a synthetic flavouring compound, chemical name methyl diisopropyl propionamide, added to some vape e liquids in small amounts to create a cold, icy sensation on the throat and tongue. It works by activating the same receptor menthol activates, but without carrying menthol's own minty taste, so fruit and dessert flavours can get a chilled finish without turning minty.
   
   
2. Is WS-23 the same as menthol?
   No. Menthol is a natural compound with its own distinct minty taste as well as a cooling effect, while WS-23 is a different, lab made molecule that triggers the same cooling receptor without that mint flavour attached. They can be used separately or together in the same e liquid, but they are chemically distinct ingredients.
   
   
3. Is WS-23 safe to vape?
   There is no confirmed answer either way yet. Research into synthetic cooling agents used by inhalation is described as limited and ongoing, with some academic exposure studies flagging levels worth further study rather than confirming harm. WS-23 has a longer track record in food, oral care and cosmetic products at low levels, but inhaled vaping use has not been assessed to the same extent.
   
   
4. What does WS-23 do in e liquid?
   It adds a cold, icy sensation to the vape without changing the underlying flavour, which is why it is used in fruit and dessert flavours that want an ice style finish. It has no effect on nicotine strength, vapour production, or any other part of the e liquid beyond that cooling sensation.
   
   
5. Why do some vapes taste icy without menthol?
   If a vape delivers a cold, icy hit but the flavour name and ingredient list say nothing about menthol or mint, that cooling is most likely coming from a synthetic cooling agent such as WS-23. It switches on the same cold sensing receptor as menthol, just without the minty taste.
   
   
6. Is WS-23 a nicotine strength or a flavour?
   WS-23 is purely a flavouring ingredient. It has no connection to nicotine strength whatsoever. A pod containing WS-23 still delivers exactly the nicotine strength stated on the label, whether that is 10mg, 20mg or anywhere between, no matter which cooling or flavour compounds are mixed in.
   
   
7. What is methyl diisopropyl propionamide?
   Methyl diisopropyl propionamide is the full chemical name for the compound commonly sold and labelled as WS-23. It is a synthetic cooling agent originally developed for food and oral care use, now also used in small amounts across the vaping flavour industry to create a cold sensation without a minty taste.
   
   
8. Does WS-23 need to be declared on vape packaging?
   No UK rule names WS-23 on its own. But every nicotine containing e liquid, WS-23 flavoured or not, must be notified to the MHRA under the Tobacco and Related Products Regulations 2016. A full ingredient and toxicology report goes with that notification, before the product can be sold.