Parabens:
Parabens are chemicals that are commonly used as preservatives in cosmetic and pharmaceutical products. Parabens disrupt hormones in your body. Once in your body, parabens can act like the hormone estrogen in both males and females. This could have an effect on things like fertility, sperm count and length of menstrual cycle.
Formaldehyde:
Formaldehyde is a carcinogen and dangerous preservative that can be absorbed through your scalp as well as seep from packaging and into the air over time. This additive can cause toxicity, affect or cause asthma, and has been linked to cancer. Formaldehyde is a highly toxic systemic poison that is absorbed well by inhalation. The vapor is a severe respiratory tract and skin irritant and may cause dizziness or suffocation. Contact with formaldehyde solution may cause severe burns to the eyes and skin.
Propylene Glycol:
Propylene Glycol is used in many styling gels, conditioners, shampoos and is the active ingredient in antifreeze. Direct contact can cause brain, liver, kidney abnormalities, renal damage, allergic reactions, and skin rashes.
Sodium laureth sulfate:
Sodium laureth sulfate (aka sodium lauryl sulfate) is used in shampoo and could potentially irritate skin conditions and cause an allergic reaction and skin rashes.
Triclosan:
Triclosan is an antibacterial and antifungal agent present in some consumer products, including toothpaste, soaps, detergents, toys, and surgical cleaning treatments. Exposure to Triclosan can lead to reproductive problems and may also affect immune response and cardiovascular function.
Phthalates:
Phthalates (aka plasticizers) are chemicals used to make plastic more durable and are linked to harmful health effects. Phthalates are linked to an increased risk of developing breast cancer and birth defects. They’re often found in hairspray and fragrance added to hair products.
Fragrance:
Fragrance (aka parfum, fragrance oils, aroma, natural fragrance) is associated with various kinds of allergic contact dermatitis. There is no legal definition for the word “natural.” So, there is a chance that what you mean by “natural” differs from what a company means by this word. Products that have “fragrance” on their label contain thousands of hidden chemicals. Some ingredients in fragranced cosmetic products can disrupt the reproductive systems. They can also cause cancer, asthma and make their way into women’s breast milk. Like many ingredients on this list, it is also an irritant to the skin and scalp, which can lead to hair loss.
Alcohol:
Alcohol is added to hair products to help hair retain moisture; however, many alcohols have a drying effect that can damage delicate strands. Alcohols that wreak havoc on dry hair usually have a “prop” in their name, like Isopropyl alcohol or propanol.
Sulfates:
You have to be careful with sulfates in shampoo. Sulfates are surfactants and they help your shampoo do its job much more effectively, but some sulfates are linked to skin irritation and may contain carcinogens. You’ll want to avoid ammonium lauryl sulfate, sodium laureth sulfate, and sodium lauryl sulfate.
Dimethicone:
Dimethicone (aka Polydimethylsiloxane or dimethylpolysiloxane) is a silicone polymer with a wide variety of uses, from cosmetics to industrial lubrication. It is particularly known for its unusual rheological properties. PDMS is optically clear and, in general, inert, non-toxic, and non-flammable.
Silicones:
Silicones are microplastics that temporarily soften and add shine to the hair for a short time. But after a while, they cause product buildup and weaken hair follicles, causing hair to become dry, dull, and prone to breakage. Silicones are hard to spot on the ingredient list, as they hide behind terms ending in cones, conols, silicones, and siloxanes.