Substances with foaming, cleansing and solubilising properties. They are obviously present in a wide range of body and hair care products.The most popular are Sodium Lauryl Sulfate (SLS) and Sodium Laureth Sulfate (SLES).
Sodium Lauryl Sulfate
Synthetic surfactant derived from ethylene oxide, used in detergents, soaps, shampoos, and shower gels. Irritating, drying, comedogenic, it can promote the formation of acne and comedones or blackheads; the damaged caused by this type of surfactant depends on concentration and duration of contact. It causes alteration of the epidermis and irritation may not be evident immediately after use. It can remain deposited on skin surface and in the follicles.
Sodium Laureth Sulfate
Synthetic surfactant derived from ethylene oxide with emulsifying and foaming properties. It is used to increase the consistency of the product. Although it is better tolerated by skin if compared with the previous one, it can cause irritation, especially to eyes, depending on quantity and concentration.
Parabens are the most widely used preservatives in cosmetic products. The six main parabens are:
There is strong evidence that these substances penetrate the skin, remain intact and are accumulated proportionally on the frequency of use.
Formaldehyde is a chemical substance that naturally is in gaseous form, but is best known as an aqueous solution. Its name is derived from formic, produced naturally by the ants, which has stinging characteristics and a very bad smell.
Thanks to its various properties, the Formaldehyde is used for multiple uses and in different areas, both in industry and in medicine. In particular, it is used in cosmetics as an antibacterial agent, a fungicide and as a preservative. It can be found in fact in hair products such as shampoos, coloring substances and smoothing, as well as in detergents and soaps.
Formaldehyde was the main ingredient in all products for straightening hair, on which was applied in the form of formalin. Some studies have shown that such use may cause toxicity, because the substance comes into direct contact with the scalp. For that reason, in 2006 the IARC (International Agency for Research on Cancer) has officially classified formaldehyde as carcinogenic to humans, by inserting it in class (proven toxicity by inhalation and ingestion suspected) of compounds with this feature.