The Dirty Dozen: 12 Skincare Ingredients to Avoid and Why

Most people check the nutrition panel on food but never read the ingredient list on their skincare. If you have ever thought about doing it, this is a good place to start. The Dirty Dozen is a term used in clean beauty to describe 12 ingredients most commonly called out by dermatologists and environmental health researchers as worth avoiding. Some are linked to hormone disruption. Others are known carcinogens or skin sensitisers. Others sit in a murkier zone of emerging research.

This is not meant to cause alarm. It is meant to help you make informed choices, starting with the products you use most and leave on your skin the longest.

1. Parabens

Synthetic preservatives that appear as methylparaben, propylparaben, butylparaben, and ethylparaben. The concern is that they can mimic oestrogen in the body and have been detected in breast tissue samples. Paraben-free formulas are now widely available across all price points.

2. Phthalates

Plasticising chemicals that extend fragrance and improve product texture. Often hidden inside the words "fragrance" or "parfum" on ingredient labels. Linked to reproductive and developmental issues in research. Avoiding products with undisclosed fragrance significantly reduces your exposure.

3. Sodium Lauryl Sulfate (SLS)

A harsh foaming detergent found in most conventional cleansers and shampoos. SLS strips natural oils and disrupts the skin barrier, which can worsen reactive skin conditions. Gentler surfactant alternatives are now widely available.

4. Formaldehyde and formaldehyde-releasing preservatives

Formaldehyde is a carcinogen. It also appears indirectly through preservatives like DMDM hydantoin and imidazolidinyl urea that slowly release it into a formula over time. Worth scanning labels for both direct and indirect sources.

5. Mineral oil

A petroleum byproduct that creates a barrier on skin and can trap bacteria and prevent proper skin respiration. Plant-derived alternatives like jojoba or rosehip are more beneficial for the skin and more environmentally responsible.

6. Synthetic fragrances

The word "fragrance" on a label can represent hundreds of undisclosed chemicals. Some are allergens, some are hormone disruptors, some accumulate in body tissue. Fragrance-free products or those using disclosed natural fragrance are the cleaner option, particularly for sensitive or reactive skin.

7. Oxybenzone

A UV filter in many chemical sunscreens linked to hormonal disruption. It has been detected in blood and breast milk after topical application, and is toxic to coral reefs. Mineral SPF with zinc oxide is the alternative most dermatologists now recommend.

8. Propylene glycol

Used in moisturisers to enhance absorption and retain moisture. Can cause skin irritation and contact dermatitis in some people, particularly at higher concentrations. Worth noting if you have reactive or sensitised skin.

9. Toluene

A petrochemical solvent used primarily in nail polish to achieve a smooth finish. Toxic to the nervous system with significant exposure and potentially harmful to fetal development during pregnancy. Most nail polish brands now offer formulas that exclude it.

10. Ethanolamines (MEA/DEA/TEA)

Used as emulsifiers and foaming agents. Can react with other ingredients to form nitrosamines, compounds classified as potentially carcinogenic. Found in many conventional moisturisers, shampoos, and cleansers.

11. Triclosan

An antibacterial agent shown to disrupt thyroid function and contribute to antibiotic resistance. Banned or restricted in many countries but still present in some products. Worth checking labels on antibacterial products specifically.

12. Hydroquinone

A skin-lightening agent that can cause irritation and a paradoxical darkening condition called ochronosis with prolonged use. Restricted or banned in the EU and several other countries. Natural alternatives like alpha arbutin, vitamin C, and niacinamide are widely considered safer options for hyperpigmentation.

Where to start

You do not need to overhaul your entire bathroom. Start with your daily leave-on products: moisturiser, sunscreen, and body lotion. Scan for parabens, synthetic fragrance, and oxybenzone first. Those three changes will cover the majority of your exposure. Apps like INCI Beauty can help you scan products before you buy.

If you want to know what is in our masks, our full ingredients glossary breaks down every ingredient we use and why it is there.