skinsafecheck Ingredient Checker

PEG 100 / PEG 150 Distearate

PEG 100, which our list names PEG 100 / PEG 150 Distearate, is rated 2 on our list, in the low band, and the number is traced: Fulton 1989 graded it 2 and Fulton 1989 graded it 2.

Like every rating here, it is for the raw ingredient tested alone, and a label does not print how much of it a product holds.

Is PEG 100 comedogenic?

2 Low

PEG 100 is rated 2 on the comedogenic scale, which is the low band.

Synthetic polymers used to cleanse the skin and thicken liquid formulations.

Comedogenic rating
2 out of 5
Band
Low: Little plugging in the rabbit-ear test. Fulton 1989 counts 0 to 1 as not significant and 2 as borderline.
Where the number comes from
Traced to Fulton 1989. The section on who rated it prints each grade.
Composition
Emulsifier / Alcohols & Derivatives
Also written as
PEG 150 Distearate
Where PEG 100 / PEG 150 Distearate sits on the 0 to 5 comedogenic scale. A single rating on our list, so the scale carries one mark. The papers we checked it against are under Sources we checked this rating against further down this page.

What a 2 means in practice

One and two are the low band. In the rabbit-ear test, Fulton 1989 counted 0 to 1 as not significant and 2 as borderline. A low grade on a rabbit's ear, which reacts more readily than human skin, is weak evidence of a problem on a person.

Two things change what this number is worth. Ingredients are listed in descending order of concentration, so peg 100 near the top of a label matters far more than peg 100 at the bottom. And the rating describes the raw ingredient on its own. A 2006 review in the Journal of the American Academy of Dermatology found that a rating for a single ingredient does not reliably predict how a finished formula behaves on human skin. The full story of the scale is here.

Check a whole ingredient list

Who rated it

Our list gives peg 100 2. These are the figures the published rabbit-ear studies we have read give it, as printed in each paper's table.

Paper Grade Tested as
Fulton 1989
rabbit ear, 10% in propylene glycol unless stated, two weeks
Grade 2 Tested as PEG 100 distearate
Fulton 1989
rabbit ear, 10% in propylene glycol unless stated, two weeks
Grade 2 Tested as PEG 150 distearate

Our list's figure is within what these papers report.

A grade is for the raw ingredient tested alone on a rabbit's ear, which reacts more readily than human skin. It says nothing about how much of it a product holds or what the rest of the formula does.

Fungal acne

PEG 100 matches rule 2, ester of a C12 to C24 fatty acid , on the fungal acne checker. An ester of stearic acid, C18. The rule comes from lab studies of what Malassezia yeast can feed on, and it is not a verdict on any product.

Common questions

Is PEG 100 comedogenic?
PEG 100 is rated 2 on the comedogenic scale, which is the low band.
Is PEG 100 non comedogenic?
Not exactly. PEG 100 is rated 2, which is the low band rather than 0. Low and non-comedogenic are different things, and only a 0 means the second one.
What is PEG 100's comedogenic rating?
2 out of 5 on our list. It is classed as Emulsifier / Alcohols & Derivatives.

Sources we checked this rating against

  1. Kligman AM, Kwong T. “An improved rabbit ear model for assessing comedogenic substances.” British Journal of Dermatology, June 1979;100(6):699–702. (opens in a new tab) The rabbit-ear assay behind published 0 to 5 comedogenicity grades.
  2. Fulton JE Jr. “Comedogenicity and irritancy of commonly used ingredients in skin care products.” Journal of the Society of Cosmetic Chemists, November/December 1989;40(6):321–333. (opens in a new tab) Rabbit ear. Each ingredient at 10 percent in propylene glycol unless stated, applied five days a week for two weeks, and graded 0 to 5 from the width of the follicles, measured by micrometer and under the microscope. The paper counts 0 to 1 as not significant, 2 to 3 as borderline and 4 to 5 as positive. Some grades depended on the supplier of the raw material, and some oils were also tested refined.
  3. Draelos ZD, DiNardo JC. “A re-evaluation of the comedogenicity concept.” Journal of the American Academy of Dermatology, March 2006;54(3):507–512. doi:10.1016/j.jaad.2005.11.1058 (opens in a new tab) Tested finished products on the backs of six people and concluded that “Finished products using comedogenic ingredients are not necessarily comedogenic.”

The rating and description above are the ones this site publishes on its A–Z list. The papers above are the ones we checked it against, and the section on who rated it says whether any of them graded this ingredient.