Parabens in skincare: what the research says

What parabens are

Parabens are esters of p-hydroxybenzoic acid, used as preservatives in cosmetics, food and medicines.¹ On a label they are named by the chain attached to the acid: methylparaben, ethylparaben, propylparaben, butylparaben and so on.

A 2005 safety assessment found that in animal studies parabens were practically non-toxic, and that they are rapidly absorbed, metabolised and excreted. In people with normal skin they were for the most part non-irritating and non-sensitising, although products containing parabens applied to damaged or broken skin had caused sensitisation.¹

One finding matters for everything below: in laboratory tests, the ability of parabens to activate the estrogen receptor increases with the size of the chain.¹ Keep that in mind when you read the entries, which differ by chain length.

Why people worry, and what the studies show

The worry traces back to a 2004 study that found parabens in 20 samples of human breast tumours, mostly methylparaben.² It showed that parabens can be found intact in the human breast. It did not show that they cause cancer, and its authors present it as a step towards measuring how much parabens build up in the body.²

A 2005 safety assessment called the possible estrogenic hazard of parabens equivocal on the available studies, and said the concern fails to consider how quickly parabens are metabolised and eliminated. It also found that the paraben structure is not indicative of carcinogenic potential.¹

A 2010 review took a more cautious view. After absorption through the skin, parabens are broken down and excreted, and little intact paraben shows up in blood or urine, but it says the breakdown products may matter for the hormone effects seen in animals. It also said that for propylparaben the safety margin looks very low when worst-case exposure is compared with the doses that had no effect in rodent studies, and that the estrogenic burden of parabens and their metabolites in blood may exceed the action of the body’s own estradiol in childhood.³

So the research does not say parabens are harmless, and it does not say they are dangerous. The reviews disagree about how much the laboratory findings matter for people, and the answer depends on which paraben, and how much.

What regulators concluded, and how the EU and India differ

In 2021 the EU’s safety committee judged propylparaben safe as a preservative at up to 0.14%. It weighed the concern about hormone effects: the data show some indications of potential effects, but not enough to regard propylparaben as an endocrine-disrupting substance.⁴

In the United States, the Cosmetic Ingredient Review expert panel assessed 21 parabens in 2020. It concluded that 20 of them are safe in cosmetics at present practices of use and concentration, when the sum of all parabens in a formula does not exceed 0.8%, and that the data for benzylparaben are insufficient.⁵ The panel was set up in 1976 by the cosmetics industry’s trade association, with support from the US Food and Drug Administration and the Consumer Federation of America.⁶

Snifff’s summaries above set out how the EU and India differ. The EU is stricter on the longer-chain parabens and bans some for lack of safety data. India’s limits are the general 0.4% alone or 0.8% in a mixture, without those extra rules. In the Cosmetics Regulation, Annex V, entry 12 allows methylparaben and ethylparaben at up to 0.4% for a single ester and 0.8% for mixtures; entry 12a allows butylparaben and propylparaben at up to 0.14% for the sum, and not in leave-on products for the nappy area of children under three; and Annex II lists isopropylparaben, isobutylparaben and several other parabens as prohibited.⁷

What “paraben-free” does and does not tell you

“Paraben-free” on a pack tells you what a formula leaves out. It does not tell you what is used instead, or that the formula is gentler. We have not found a study that compares paraben-free and paraben-containing products for skin outcomes.

Another widely used preservative is phenoxyethanol, which has its own page.

Parabens in pregnancy and breastfeeding

Snifff’s notes differ by paraben, as the risk labels do. For propylparaben and butylparaben the concern is estrogenic activity. For isopropylparaben and isobutylparaben, Snifff cites endocrine disruption and a lack of safety data. That fits the laboratory finding that estrogenic activity rises with chain length.¹

For methylparaben and ethylparaben, Snifff found no pregnancy-specific evidence. That is different from cleared: it means unstudied.

Evidence on cosmetic products in pregnancy is limited overall, so ask your doctor or midwife about the specific product you use.⁸

What you will see on the label

Parabens are listed by name, such as Methylparaben or Propylparaben. Snifff has an entry for each, and reads them across a range: Low risk for methylparaben and ethylparaben, Moderate risk for propylparaben and butylparaben, and High risk for isobutylparaben and isopropylparaben.

Those labels describe each ingredient on its own. For the rest of the formula, see what the score means and how to read the list.

As Snifff shows it

Parabens

Methylparaben

Low risk

Pregnancy and nursing

We found no pregnancy- or lactation-specific evidence for this ingredient.

Ethylparaben

Low risk

Pregnancy and nursing

We found no pregnancy- or lactation-specific evidence for this ingredient.

Propylparaben

Moderate risk

Pregnancy and nursing

Use with caution during pregnancy and lactation: propylparaben has estrogenic activity and is linked to altered maternal pregnancy hormones.

Regulatory gap

The EU caps this paraben at 0.14% and bans it in leave-on diaper-area products for children under 3. India allows 0.4% alone or 0.8% in mixtures without that child-use ban.

Butylparaben

Moderate risk

Pregnancy and nursing

Use with caution during pregnancy and lactation: butylparaben has estrogenic activity.

Regulatory gap

The EU caps this paraben at 0.14% and bans it in leave-on diaper-area products for children under 3. India allows 0.4% alone or 0.8% in mixtures without that child-use ban.

Isobutylparaben

High risk

Pregnancy and nursing

Use with caution during pregnancy and lactation: this paraben is an endocrine disruptor and lacks sufficient safety data.

Regulatory gap

The EU bans this paraben because there is not enough safety data. India has no ingredient-specific restriction.

Isopropylparaben

High risk

Pregnancy and nursing

Use with caution during pregnancy and lactation: this paraben is an endocrine disruptor and lacks sufficient safety data.

Regulatory gap

The EU bans this paraben because there is not enough safety data. India has no ingredient-specific restriction.

Wording as it appears in the extension, which can change between releases.