1.  Butylated HydroxyAnisole and Butylated Hydroxytoluene (BHT)

Use: These synthetic antioxidants are commonly used to extend product shelf life.

Con: These are not like natural, good-for-you antioxidants. Instead, they are likely carcinogens and hormone disruptors that may cause liver damage.

2.  Ethylenediaminetetraacetic Acid (EDTA)

Use: EDTA is a chelating (binding) agent added to cosmetics to improve product stability. It’s supposed to keep active ingredients in a formula from binding with trace elements, like minerals, present in water. It also prevents a product’s texture, odor, and consistency from changing.

Con: It has been shown to cause irritation to the eyes, skin, and lungs. And it may be toxic to non-reproductive organs.

3.  Hydroquinone

Use: This skin-bleaching and skin-lightening chemical is meant to inhibit the production of melanin.

Con: In the short term, this can help with dark spots and discoloration. In the long term, though, the chemical is linked to cancer, organ toxicity, and skin irritation.It can also cause a skin disease called ochronosis, which causes permanent blue-black lesions to appear on the skin.

4.  Oxybenzone

Use: This sunscreen agent and ultraviolet light absorber are found in the majority of over-the-counter sunscreens.

Con: It acts like estrogen in the body and, as a result, is linked to endometriosis and altered sperm production.

This high-risk chemical can cause irritation, sensitization, allergic reactions, and possible hormone disruption. On top of that, it has been known to be harmful to coral reefs, which is why it’s been banned in Hawaii.

5.  Parabens (methyl-, isobutyl-, propyl- and others)

Use: Parabens are a family of preservatives (methylparabens, propylparabens, butyl parabens, and ethyl parabens) that are commonly used to extend shelf life by preventing the growth of bacteria and mold.

Con: According to the European Commission’s Scientific Committee on Consumer Products, longer chain parabens like propyl and butyl paraben – along with their branched counterparts, isopropyl and isobutyl parabens – may disrupt the endocrine system and cause reproductive and developmental disorders.

Overall, the FDA acknowledges several studies linking parabens – which also mimic estrogen – to breast cancer, skin cancer, and decreased sperm count. Despite that, it has yet to rule them as harmful.

6.  Phthalates (DBP, DEHP, DEP and others)

Phthalates are a class of plasticizing chemicals used to make products more pliable and to make fragrances stick to the skin.

Con: They can be extremely dangerous, particularly to children. It’s best to avoid them altogether (even if you’re an adult) as they can be serious endocrine disruptors and may even cause birth defects and breast cancer. Congress has already banned several types of phthalates from children’s products.

7.  Polyethylene Glycol (PEG compounds)

Use: PEGs are widely used in cosmetics as thickeners, solvents, softeners, and moisture carriers. They are also the primary components of those tiny plastic beads found in face scrubs and exfoliating washes.

Con: While PEGs themselves aren’t harmful, they can cause irritation when used on broken skin.

And they go right through our sewage systems into waterways, where they are often consumed by marine animals.

8.  Silicone

Use: It’s used to enhance the feel and texture of the product and the skin, making it feel soft and smooth.

Con: Silicone is interesting because it’s not actually a toxic ingredient. That said, it can prevent additional moisture from getting into your skin, thereby dehydrating your pores and throwing off your skin’s natural regulatory processes.

9.  Sodium Lauryl Sulfate and Sodium Laureth Sulfate (SLS and SLES)

Surfactants, also known as surface-active agents, are substances that reduce the surface tension between two liquids, a liquid and a gas, or a liquid and a solid

Con: SLS and SLES are surfactants that can cause skin irritation and trigger allergic reactions. They have been shown to contribute to significant skin irritation, canker sores, disruption of the skin’s natural oil balance, and eye damage – yikes! They’re also widely believed to contribute to cystic acne, particularly around the mouth and chin.

Also known as: Sodium laureth sulfates, sodium lauryl sulfate, sodium laureth sulfate, alkylbenzene sulfonate, sodium cocoyl sarcosinate.

10.  Formaldehyde

Use: Formaldehyde is a preservative used to prolong the shelf life of many self-care products.

Con: It is widely understood to cause allergic reactions and rashes in beauty products

11.  Aluminum

Use: It’s primarily found in the form of alumina (aluminum oxide) or other aluminum-containing compounds, and is sometimes used as a thickening agent, absorbent, or abrasive.

Con: Some research suggests that aluminium may have endocrine disrupting properties and has been linked to breast cancer, breast cysts, and Alzheimer’s disease.

Aluminium production can be resource-intensive and environmentally damaging.

12.  Siloxane

Use: Siloxane can provide smoothness and lubricity, so you’ll often find it in moisturizer and foundation.

Con: It is among the toxic skincare products for its effect on endocrine disruption and links to fertility issues.