pH decides what proportion of a pouch’s nicotine is in the free-base form your mouth can actually absorb, and that proportion varies enormously between products. When CDC scientists measured 37 nicotine pouch brands, pH ran from 6.86 to 10.1 and free nicotine from 7.7% to 99.2% of the total. Two cans printed with the same milligrams can therefore deliver very different doses.
This is the mechanism behind the single most common complaint I see from people new to pouches: that two products with identical numbers on the tin feel nothing alike. Part of the answer is dose, part is moisture, part is the pouch material — and a large part is pH, which almost nobody prints and no regulator requires. Here is what has actually been measured, who paid for the measuring, and where the evidence stops.
Nicotine is a weak base, and that is the whole mechanism
Nicotine exists in two forms in a wet environment: protonated (charged) and unprotonated, usually called free-base. Only the uncharged form crosses a membrane easily. The UK’s Committee on Toxicity puts it plainly: “nicotine is a weak base with pKa 8.0 and is not well absorbed in the ionised state”, and “Absorption of nicotine from saliva across the buccal mucosa increases with the pH of the saliva”. Uncharged forms, it adds, “are transferred more readily due to their higher lipid membrane solubility”.
The split between the two forms follows the Henderson–Hasselbalch equation, which is why raising a pouch’s pH by less than a single point can change the deliverable dose severalfold. The German Federal Institute for Risk Assessment gives one anchor point: “At a pH of 7.4, nicotine is present in the bloodstream in approximately 69% ionic and 31% non-ionic (free-base) proportions.”
If you want the ladder across the range a pouch actually occupies, I have to be clear that no primary source I could open publishes it as a table, so what follows is my own arithmetic from the equation, using a pKa of 8.0: roughly 9% free base at pH 7.0, 24% at pH 7.5, 50% at pH 8.0, 76% at pH 8.5 and 91% at pH 9.0. Treat those as the shape of the curve, not as measurements. The shape is the point — the curve is steepest exactly where pouches sit.
What has actually been measured
Four independent datasets exist, and they do not quite agree, which is itself informative.
The United States, 37 brands. Stanfill and colleagues at the CDC’s Division of Laboratory Sciences published the foundational survey in Nicotine & Tobacco Research on 26 May 2021. Verbatim: “Nicotine pouch products varied in pouch content mass, moisture content (1.12%‒47.2%), alkalinity (pH 6.86‒10.1), and % free nicotine (7.7%‒99.2%).” And: “Total nicotine content ranged from 1.29 to 6.11 mg/pouch, whereas free nicotine ranged from 0.166 to 6.07 mg/pouch.” Free nicotine was “calculated for each product using total nicotine, product pH, the appropriate pKa, and the Henderson–Hasselbalch equation.” The paper carries a US-government public-domain statement, so its authorship is federal; its full text is paywalled and I could not retrieve a separate funding or competing-interests declaration, which I would rather say than imply.
Europe, 46 samples. Mallock and colleagues at BfR published in Tobacco Control: “In total, 46 different pouch samples from 20 different producers were obtained.” Their result: “Analysed pH values of pouch extracts ranged from 5.5 to 10.5 with a median of 8.8”, and “Median proportion of free-base nicotine was 86% thus facilitating fast absorption.” Funding: “The project was financially supported by intramural funding of the German Federal Institute for Risk Assessment (BfR) (SFP Grant No. 1322-772).” Competing interests: “None declared.”
That European median of 86% free base is the number I would carry away from this article. It means the typical pouch on a European shelf is not delivering a fraction of its nicotine content to your mucosa — it is delivering nearly all of it, as fast as the pouch dissolves.
Two products, named. Swedish Match’s own researchers published pH figures for specific products in BMC Chemistry: ZYN dry at “8.3”, ZYN moist at “8.3”, and General Portion Original Large snus at “8.9”, with unprotonated nicotine of 4.87±0.36 mg/g, 7.87±0 mg/g and 7.11±0.28 mg/g respectively, measured with “CORESTA Recommended Method No. 69”. Funding, verbatim: “The study was funded by Swedish Match AB, who markets the ZYN and General products described in the article.” Competing interests: “All authors are either employees of or otherwise funded by Swedish Match AB.” That is manufacturer-generated data about the manufacturer’s own products, and it should be read as such — but it is the only place a named pouch’s pH is public at all. In FDA’s own review of the same company’s application for the same products, every pH value is redacted as confidential commercial information.
The comparison table
| Product category | pH measured | Free-base nicotine | Who measured it, and who paid |
|---|---|---|---|
| Nicotine pouches, US market (37 brands, 6 makers) | 6.86–10.1 | 7.7%–99.2% of total | CDC Division of Laboratory Sciences, 2021. Federal authorship; no separate funding statement obtainable |
| Nicotine pouches, European market (46 samples, 20 producers) | 5.5–10.5, median 8.8 | Median 86% (IQR 62%–98%) | BfR, 2022. Intramural BfR funding; no competing interests declared |
| ZYN dry / ZYN moist | 8.3 / 8.3 | 4.87 / 7.87 mg per gram unprotonated | Swedish Match AB researchers, 2023. Funded by Swedish Match AB, which markets the products |
| Swedish snus (General Portion Original Large) | 8.9 | 7.11 mg per gram unprotonated | As above |
| Swedish snus, 25 brand families | 5.87–9.10 | 0.08–16 mg/g free nicotine | CDC, 2020. “The authors have no support or funding to report”; no competing interests |
| US moist snuff | 5.54–8.62 | 0.3%–79.9% of total | CDC, 2008. “All research was supported by internal funds of the Centers for Disease Control and Prevention”; no conflicts |
Read down the pH column and the pattern is obvious: traditional American moist snuff is the acidic end of the oral-nicotine world, and modern nicotine pouches reach far higher. A product at pH 10 is not a slightly stronger version of a product at pH 7. It is a different delivery mechanism wearing the same packaging.
Does pH actually change how much nicotine reaches your blood?
Yes, and the size of the effect has been measured once, in a product category adjacent to pouches. Writing in Clinical Pharmacology & Therapeutics on 27 February 2022, Neal Benowitz described a trial in which smokeless tobacco pH was experimentally manipulated: “The product pH was varied from 5.0 to 8.6, resulting in a variation in freebase nicotine from 0.1 to 79%.” The outcome: “Plasma nicotine AUC increased four-fold across the pH range of 5.0 to 8.6.” He notes that the underlying study “is the first to study nicotine absorption and pharmacologic effects with experimental manipulation of the pH in a single commercial product.” His own disclosure is extensive and I will quote it rather than summarise it: “Dr. Benowitz has been a consultant to Pfizer and Achieve Life Sciences, companies that market or are developing smoking cessation medications, and has been a paid expert witness in litigation against tobacco companies.” The work was supported by NIH grants.
Two caveats that matter. That was moist snuff, not a pouch. And a fourfold swing in nicotine exposure from pH alone, with dose held constant, is the clearest statement available of how much this variable is worth.
The regulator treats it as load-bearing too. In its technical review of Helix Innovations’ on! PLUS applications, FDA explains why it compares pH between products at all: “pH moderates nicotine exposure by allowing free nicotine to more readily cross biological membranes, including oral mucosa”, citing Chen 1999, Nair 1997, Nielsen 2002 and Wilhelm 2022. The same review describes the products as containing “tobacco-derived nicotine, flavor ingredients, artificial sweeteners, stabilizers, fillers, and pH adjusters” — pH adjusters are a declared product component, not an accident.
How makers raise the pH: the ingredients
The salts are not exotic. Swedish Match’s own paper lists ZYN dry as containing “pH adjusters (sodium carbonate and sodium bicarbonate)” and ZYN moist as containing “pH adjusters (sodium carbonate and calcium chloride)”. BfR reports the same category of ingredients from manufacturer declarations — sodium carbonate and hydrogen carbonate, citric acid and flavourings — and a BfR-funded screen of 48 pouches found “acidity regulators (mostly sodium carbonate)” among the most abundant ingredient categories. FDA’s own guidance for smokeless products notes that “ingredients such as sodium carbonate, potassium acetate, and ammonia can influence the pH of a smokeless tobacco product, and a change in pH can impact the amount of free nicotine released from the tobacco product.”
So when a brand lists sodium carbonate, it is telling you — if you know how to read it — that the pH has been engineered. What it is not telling you is the resulting number.
A disagreement about nicotine’s pKa, and who is on which side
The calculation depends entirely on the pKa used, and the published values differ in a way that is not cosmetic. CDC’s 2013 paper uses the “pKa value of the pyrollic nitrogen of nicotine (8.02)”. BfR’s group uses “the pKa of 8.01 of the pyrrolidine moiety of nicotine.” BfR’s opinion and the UK’s COT both say 8.0. But a 2026 modelling paper in Scientific Reports uses “approximately 7.8 (7.7–7.9)” — and its funding statement reads: “This research, including the clinical study and all analyses, was solely funded by Altria Client Services LLC.”
I would not read that as anything sinister, but I would note the direction. A lower pKa raises the calculated free-base fraction at any given pH: at pH 8.0, 50% on a pKa of 8.0 becomes about 61% on a pKa of 7.8. When a number is derived rather than measured, the assumption behind it is part of the result, and anyone comparing free-nicotine figures across papers should check which pKa each one used before treating them as commensurable.
The part where pH is not the answer: the “hit” is partly coolant
This is the finding I think matters most, because it reframes the question. The stinging, tingling, cold sensation most people call the hit is not one thing, and nicotine is not all of it.
Nicotine is a direct irritant: a 2009 paper in Nature Neuroscience established that “micromolar concentrations of nicotine activated heterologously expressed mouse and human TRPA1” — the same receptor channel that responds to mustard oil and tear gas — and noted that “Topical application of nicotine, as used in nicotine replacement therapies, causes irritation of the mucosa and skin.” That paper contains no competing-interests statement at all, which I mention because its absence is not the same as a declaration of none.
The cooling, meanwhile, is a different receptor and usually a different molecule. Jabba and colleagues, writing in Tobacco Control on 2 January 2025, found that “Zyn Chill exclusively contained WS-3, an odourless synthetic cooling agent” at 234±7 μg per pouch, with Peppermint at 201±11 μg and Spearmint at 209±15 μg. Chill extracts activated the cold receptor TRPM8 with far higher efficacy than the mint products. And then the sentence that closes the loop: “Similar to menthol, synthetic cooling agents have analgesic activity in rodents, suggesting that WS-3 may soothe the sensory irritation caused by nicotine in ONPs.” The work was supported by National Institute on Drug Abuse grants; one co-author declares consultancy and advisory relationships with pharmaceutical companies, and “The other authors have no disclosures to report.”
FDA’s own reviewer reached a compatible conclusion from the application file, finding the coolant in ZYN’s Chill products present at concentrations “at least 5 times higher” than those reported in the literature as eliciting a cooling sensation in humans. The coolant’s identity and amount are redacted in the public version.
Put together: a high-pH pouch delivers more free-base nicotine, which irritates; a coolant may be masking that irritation while producing a cold sensation of its own. Which means a pouch that feels mild is not necessarily delivering less. If you are using sensation as a proxy for dose, that proxy is actively engineered. Our guide to nicotine salts versus free-base covers the formulation side, and how pouches actually work the absorption side.
What nobody has measured
Three honest gaps, because an article like this is only worth reading if it marks its own edges.
Nobody has measured pH inside a human mouth during pouch use. The only time-course data is in vitro, in artificial saliva, in the Altria-funded modelling paper — and it runs the opposite way to the intuition: “the pH of the artificial saliva increased over time in the presence of DRYFT and ZYN ONPs, eventually reaching a pH of around 7.5”, while “no significant change in the pH of the artificial saliva was observed by VELO”. That is the pouch raising the medium’s pH, not saliva neutralising the pouch.
No pharmacokinetic study of pouches has manipulated pH. The pooled analysis of pouch trials stratifies by milligrams only; the only experimental pH manipulation was in moist snuff. So the fourfold figure above is the best available estimate and it is borrowed from a neighbouring product.
And no source apportions the perceived hit. The mechanistic separation between TRPM8 cooling and TRPA1 irritation is established. The split — how much of what you feel is free-base nicotine, how much is alkalinity itself, how much is coolant — has not been quantified by anyone.
Nobody regulates this
Worth stating plainly: no regulator anywhere sets a limit on a pouch’s pH or on its free-nicotine content. FDA requires applicants to report pH and compare it to a predicate product, but publishes no threshold. A survey of regulatory approaches across 67 countries found limits on nicotine concentration and on additives; it records no country setting a pH or unprotonated-nicotine limit. Poland caps tobacco-free pouches at 20 mg of nicotine per gram; the Netherlands set a nicotine-mass threshold. All of these regulate how much nicotine is in the pouch. None regulates how much of it your mouth can absorb.
Frequently asked questions
Can I tell a pouch’s pH from the can? No. No manufacturer publishes a pH figure, and no label is required to carry one. The closest proxy is the ingredient list: sodium carbonate or sodium bicarbonate means the pH has been raised deliberately.
Does a higher pH mean a stronger pouch? It means more of the nicotine present is in the absorbable form, so for a given milligram figure, yes, a higher-pH product will tend to deliver more. But dose and pH are separate variables, and the can only tells you one of them.
Is a high-pH pouch more damaging to my gums? I cannot tell you that from the evidence I have. Alkalinity against mucosa is a plausible mechanism for the burning people report, and nicotine is independently an irritant via TRPA1, but I found no study measuring gum outcomes against product pH. Anyone claiming a clean answer here is going beyond the literature.
Why do two 6 mg pouches feel so different? Free-nicotine content is the largest single reason — across the US survey it ranged from 7.7% to 99.2% of total nicotine. Add moisture, which determines how fast the pouch releases, and coolants, which change what you feel without changing the dose, and the milligram number is perhaps the third most important thing about the can.
Do mints have a higher pH than fruit flavours? Not established. The flavour and the pH are independent formulation choices, and no dataset I found groups pH by flavour family.
Sources
- Stanfill S, Tran H, Tyx R, et al., “Characterization of Total and Unprotonated (Free) Nicotine Content of Nicotine Pouch Products”, Nicotine & Tobacco Research 2021;23(9):1590–1596, doi 10.1093/ntr/ntab030, published 26 May 2021. Authors at the Division of Laboratory Sciences, Centers for Disease Control and Prevention; the paper carries a US-government public-domain statement. Full text paywalled; no separate funding or competing-interests statement was obtainable.
- Mallock N, Schulz T, Malke S, et al., “Levels of nicotine and tobacco-specific nitrosamines in oral nicotine pouches”, Tobacco Control, doi 10.1136/tc-2022-057280, online 5 August 2022. Funding: intramural BfR (SFP Grant No. 1322-772). Competing interests: “None declared.”
- Bundesinstitut für Risikobewertung, Health risk assessment of nicotine pouches, BfR Opinion No. 023/2022, 7 October 2022.
- Mallock-Ohnesorg N, et al., “Oral nicotine pouches with an aftertaste? Part 1”, Archives of Toxicology, doi 10.1007/s00204-023-03538-9, 30 June 2023. Funding: intramural BfR. Competing interests: none declared.
- Back S, Masser AE, Rutqvist LE, Lindholm J, BMC Chemistry 2023;17:9, doi 10.1186/s13065-023-00918-1. Funding: “The study was funded by Swedish Match AB, who markets the ZYN and General products described in the article.” Competing interests: “All authors are either employees of or otherwise funded by Swedish Match AB.”
- Lawler TS, Stanfill SB, Zhang L, Ashley DL, Watson CH, “Chemical characterization of domestic oral tobacco products”, Food and Chemical Toxicology 2013;57:380–386, CDC Stacks. Funding: internal CDC funds; “The authors report no conflicts of interest.”
- Lawler TS, Stanfill SB, Tran HT, et al., “Chemical analysis of snus products from the United States and northern Europe”, PLoS ONE 2020;15(1):e0227837, doi 10.1371/journal.pone.0227837. Funding: “The authors have no support or funding to report.”
- Richter P, Hodge K, Stanfill S, Zhang L, Watson C, “Surveillance of moist snuff”, Nicotine & Tobacco Research 2008;10(11):1645–1652. Funding: internal CDC funds; no conflicts. The pH ceiling is quoted as 8.62 in the paper’s own table and restated as 8.61 by the UK COT; we report both.
- Benowitz NL, “The central role of pH in the clinical pharmacology of nicotine”, Clinical Pharmacology and Therapeutics, PMC9035094, 27 February 2022, discussing Wilhelm J, Mishina E, Viray L, Paredes A, Pickworth WB, doi 10.1002/cpt.2493. The underlying trial could not be opened directly (publisher returns 403), so the figures here are as Benowitz reports them. Supported by NIH grants U54 HL147127 and DA03924; his disclosure is quoted in full in the body.
- UK Committee on Toxicity, Updated discussion paper on the bioavailability of nicotine and other ingredients from the use of oral nicotine pouches, TOX/2022/22, 18 March 2022. Government advisory paper; carries no funding statement.
- FDA, Technical Project Lead Review, Helix Innovations LLC (on! PLUS), December 2025; and Technical Project Lead Review, ZYN, 13 January 2025. pH values and coolant quantities are redacted as confidential commercial information in both.
- FDA, Appendix: Information to Consider for Smokeless Tobacco Products, version 10/2/18.
- Talavera K, Gees M, Karashima Y, et al., “Nicotine activates the chemosensory cation channel TRPA1”, Nature Neuroscience 2009;12, doi 10.1038/nn.2379. Supported by KU Leuven, FWO and Belgian Science Policy grants. The paper contains no competing-interests statement.
- Jabba SV, Erythropel HC, Woodrow JG, et al., “Synthetic cooling agent in oral nicotine pouch products marketed as ‘Flavour-Ban Approved'”, Tobacco Control 2025;34(1):106–110, doi 10.1136/tc-2023-058035, 2 January 2025. Supported by NIDA grant R56DA055996 and cooperative agreement U54DA036151.
- Knopp MM, Jørgensen JR, Li X, et al., “Development of a model to predict nicotine pharmacokinetics from oral nicotine pouches”, Scientific Reports, 4 June 2026. Funding: “This research, including the clinical study and all analyses, was solely funded by Altria Client Services LLC.”
- Heshmati J, Bates EL, Shahen S, et al., Drug and Alcohol Dependence Reports 2025;17:100389, doi 10.1016/j.dadr.2025.100389. Funding: “None”.
- Duren M, Atella L, Welding K, Kennedy RD, “Nicotine pouches: a summary of regulatory approaches across 67 countries”, Tobacco Control 2024;33:e32–e40, doi 10.1136/tc-2022-057734. Funding: Bloomberg Philanthropies’ Bloomberg Initiative to Reduce Tobacco Use, with CDC/NIOSH support for one author. Competing interests: “None declared.”
Last verified 3 October 2026.