PEG-16 Lanolin
PEG-16 lanolin is rated Clogging, on one 1989 rabbit-ear reading. What Fulton printed matters more than usual here: his row reads "PEG 16 lanolin (Solulan 16)," and Solulan 16 is a four-component emulsifier blend, so the 4 belongs to the blend as printed rather than to the ethoxylated lanolin alone — and the man who produced the 4 wrote that its non-lanolin ingredients, not the lanolin, were probably doing the clogging.
Ethoxylated lanolin. Scored positive, though Fulton blamed its non-lanolin co-ingredients.
What it is
An ethoxylated lanolin: whole lanolin reacted with ethylene oxide until it turns into a water-dispersible surfactant, used to emulsify oil and water and to stabilise foam. It is the kind of ingredient that lets an otherwise oily conditioner or lotion rinse and spread, rather than an emollient you would add for its own feel. The name to hold on to is the trade name, because the whole page turns on it. Fulton tested a product he called Solulan 16, and printed the row as "PEG 16 lanolin (Solulan 16)." Solulan 16 is still sold — by Lubrizol — and its current technical datasheet describes it as "a 100% active complex of ethoxylated lanolin and ethoxylated fatty alcohol," with the INCI name Ceteth-16 (and) Laneth-16 (and) Oleth-16 (and) Steareth-16. In other words it is not a single molecule. It is the ethoxylated lanolin (laneth-16) blended with three ethoxylated fatty alcohols — ceteth-16 from cetyl alcohol, oleth-16 from oleyl alcohol, steareth-16 from stearyl alcohol. The supplier lists it as an oil-in-water emulsifier and foam stabiliser for shampoos, mousses, body washes and body lotions, creams and gels. So the label ingredient people look up as "PEG-16 Lanolin" and the material Fulton actually put on a rabbit's ear are joined by his own parenthetical — and that material is a blend. Keep that in view; it is the difference between a score for the ethoxylated lanolin and a score for the mixture it ships in.
Why we rate it Clogging
We rate it Clogging at Low confidence, on a single legacy rabbit-ear assay. The number, and its scale. In James Fulton's 1989 rabbit-ear survey in the Journal of the Society of Cosmetic Chemists — the source of nearly every comedogenic score in circulation — Table I prints one row: "PEG 16 lanolin (Solulan 16) — 4," on his 0–5 scale. By Fulton's own published key, a 4 is in the band he called "considered positive" (0 to 1 "not considered significant," 2 to 3 "borderline," 4 to 5 "positive"). The asterisk that appears on several rows nearby — his footnote "results depend on source of raw material" — is not on this one, and it is not on this section, so no such caveat attaches to the number. What is unusual here, and worth saying plainly, is that the label name does appear in the row. Most numbers this site examines turn out to belong to a different molecule than the label they follow around — the famous coconut 4 is coconut butter's, and so on. This one is not quite that. Fulton prints PEG 16 lanolin, but he prints it with a parenthetical, "(Solulan 16)," and the parenthetical is the whole of the matter: what he scored was a four-component trade blend. The 4 is the blend's, as printed, and that is how we attribute it. But the material Fulton named is a blend, and he said so himself, in the same paper. His prose reads: "PEG 16 lanolin (Solulan 16) is quite comedogenic and irritating, perhaps secondary to the combination of nonlanolin additives: ceteth-16, oleth-16, and steareth-16." The author of the 4 suspected the ethoxylated fatty alcohols in the mixture, not the ethoxylated lanolin, of producing the result. That is his hypothesis, offered with "perhaps," not a second experiment isolating the parts — and it is worth exactly what a hypothesis is worth. But it means the paper does not tell you that the lanolin component is what clogs. It tells you a blend containing it scored 4, and that the person who ran the assay would not pin that on the lanolin. Two smaller readings of the same table point the same way. Fulton's concluding list of the paper's "major offenders" — isopropyl myristate, the acetylated-lanolin-alcohol material, and the lauric-acid derivatives such as laureth-4 — does not include PEG-16 lanolin, even though it scored as high as some materials that are on the list. And his ethoxylated lanolins do not fall on any single line: in the same section anhydrous lanolin scored 0–1*, laneth-10 scored 2, the more heavily ethoxylated PEG-75 lanolin scored 0, and PPG-12/PEG-65 lanolin oil scored 2. Fulton's own text remarks that the classic anhydrous lanolins are "not as comedogenic as the moderately ethoxylated derivatives (laneth 10)." A reader could build a tidy story about ethoxylation out of those numbers; we are not going to, because a handful of rows from one survey is not a rule, and the rows do not agree on one. One reading from the wider family is worth recording, and it is not a second reading of this material. Fulton's earlier 1984 rabbit-ear table prints "Ethoxylated lanolin — 3," which under that paper's own key — 1 to 2 not significant, 3 or above considered positive — is a positive result. But "ethoxylated lanolin" there is an umbrella name for a class, not the Solulan 16 blend, and the two papers do not share a grade key. It sits beside the 4 as related-family evidence, not as corroboration of it. The rating is Clogging because the blend Fulton printed as "PEG 16 lanolin (Solulan 16)" scored in his positive band, and nothing we found pulls the other way. It is Low confidence because that is the whole of the evidence: one rabbit-ear reading, from one laboratory, in 1989.
What the evidence doesn’t tell you
Everything above rests on a single assay, and on rabbits' ears. The method, stated plainly: roughly 10% of the ingredient in propylene glycol, about 1 mL applied to the inner ear of three New Zealand albino rabbits, five days a week for two weeks, the follicles then scored for keratosis under a micrometer. Fulton called his own survey "not at all definitive but simply designed to stimulate research," and warned that the rabbit ear is sensitive enough that "not everything that irritates this model will also irritate human skin." Those cautions apply to this 4 as much as to any other number he printed. We found no second measurement to check it against. We identified no other comedogenicity assay of PEG-16 lanolin or Solulan 16, and no human study of either, in the sources we searched. Morris and Kwan's 1983 rabbit-ear survey — the other assay of this era, on the same 0–5 scale, in a different laboratory — tested seven lanolin materials (anhydrous lanolin, two lanolin oils, lanolin alcohol, isopropyl lanolate, the lanolin acids, and an acetylated-lanolin-alcohol material) and none of them was this one. Fulton's own 1984 table carries no row under either name, only the umbrella "Ethoxylated lanolin" discussed above, and Nguyen's 2007 series carries neither. So the 4 stands alone; it is neither corroborated nor contradicted by a second document. And the deeper limit is the one built into the material. The 4 is a score for a multi-component emulsifier, and we found no assay that takes the blend apart and tests the ethoxylated lanolin on its own. How much of the number belongs to the lanolin and how much to the ceteth-16, oleth-16 and steareth-16 alongside it is not something the paper settles. Fulton's own suspicion points away from the lanolin — but "perhaps secondary to" is a sentence, not a control arm, and reading it as an exoneration would be the same error, run in reverse, that this site exists to correct. What is established is narrow: the blend as tested, printed as "PEG 16 lanolin (Solulan 16)," scored 4. What each part of it does alone is unmeasured. A concentration caveat cuts both ways and we will not lean on either edge of it. The rabbit assay used the ingredient at roughly 10%; how that relates to the levels PEG-16 lanolin is used at in a finished product is unestablished, and we hold no measured in-use figure for it. Fulton warned in his conclusion against assuming that lower concentrations of his positive materials are automatically safe — but he measured no dose-response for this one, so neither "it is diluted, therefore fine" nor "it clogs at any level" is a claim the evidence supports.
Where you’ll see it
As an oil-in-water emulsifier and foam stabiliser. Lubrizol's datasheet for Solulan 16 lists it in shampoos and mousses, body washes, and body lotions, creams and gels — those are the supplier's stated application categories, not a market audit we have run, and a position on an ingredient list is not a dose. On a label it appears as PEG-16 Lanolin, or, when the material is the Solulan 16 blend, as its component names: Ceteth-16, Laneth-16, Oleth-16 and Steareth-16.
Sources
Each source says what it actually is. Several widely-cited “sources” for comedogenic ratings are republishing the same 1989 assay, and counting them as independent agreement is how a thin evidence base gets made to look thick.
- Fulton JE. "Comedogenicity and irritancy of commonly used ingredients in skin care products." J Soc Cosmet Chem 40:321–333 (1989) The primary source, and the origin of essentially every comedogenic number in circulation, including this one. Read off a verbatim transcription of Table I taken from the journal scan rather than from a list quoting it. Method: the ingredient at roughly 10% in propylene glycol, inner ear of New Zealand albino rabbits, three rabbits per assay, five days a week for two weeks, follicular keratosis measured under a micrometer — a 0–5 scale on which Fulton's own key makes 4–5 "considered positive." Its Section I row reads "PEG 16 lanolin (Solulan 16) — 4," with no section or cell asterisk, and its prose states the material "is quite comedogenic and irritating, perhaps secondary to the combination of nonlanolin additives: ceteth-16, oleth-16, and steareth-16." Fulton called the survey "not at all definitive but simply designed to stimulate research." Cited both for the score and for the author's own account of what he thought caused it.
- Fulton JE, Pay SR, Fulton JE III. "Comedogenicity of current therapeutic products, cosmetics, and ingredients in the rabbit ear." J Am Acad Dermatol 10(1):96–105 (1984) Fulton's earlier rabbit-ear paper, on its own 0–5 key — 1 to 2 not significant, 3 or above considered positive. It prints "Ethoxylated lanolin — 3," a positive result under that key. Cited as related-family evidence only, and not as a second reading of this page's material — "ethoxylated lanolin" is an umbrella name for a class, and the table carries no PEG-16 lanolin or Solulan 16 row. It is the same investigator, not an independent laboratory, and it is still a rabbit's ear.
- Solulan™ 16 lanolin derivative, Lubrizol technical datasheet, as reproduced by SpecialChem Manufacturer documentation for the trade product Fulton tested, read on SpecialChem's reproduction of Lubrizol's datasheet rather than on Lubrizol's own page. It describes the product as "a 100% active complex of ethoxylated lanolin and ethoxylated fatty alcohol," INCI Ceteth-16 (and) Laneth-16 (and) Oleth-16 (and) Steareth-16, an oil-in-water emulsifier and foam stabiliser. Not a comedogenicity study; a statement of what the tested substance is — and it corroborates, from a different direction, the multi-component makeup Fulton named in 1989. The limit is the usual one: it confirms what Lubrizol sells today, not that the 1989 sample had this exact composition.
- Morris WE, Kwan SC. "Use of the rabbit ear model in evaluating the comedogenic potential of cosmetic ingredients." J Soc Cosmet Chem 34:215–225 (1983) An independent rabbit-ear assay on the same 0–5 scale, six years before Fulton 1989 and in a different laboratory — not a republisher of him. Cited here for what it does NOT contain: we hold its transcribed rows, and among its seven lanolin materials there is no PEG-16 lanolin and no Solulan 16. It is the obvious place a second reading of this material would live, and it isn't there — which is why Fulton's 4 stands uncorroborated rather than confirmed.
Others in the same family
Lanolin & derivatives behave similarly enough that the evidence for one is often wrongly read across to the others. These are its structural relatives, not a guess. What the evidence says about lanolin & derivatives as a family ›
Last reviewed 2026-08-12 · How we decide