There have been many questions surrounding the labeling of nail polishes being 5 Free, 7 Free, or 9 Free. This is the true difference:
Generally nail polish will, at the very least, be 3 Free. This means that the nail polish is free of what is known as the “Toxic Trio”, which are Dibutyl Phthalate, Formaldehyde, and Toluene. These ingredients are commonly used to assist in reducing cracking and improving flexability. Chip free formulas often still contain these ingredients so always read the labels if you are concerned.
5 Free nail polish is the common standard now. While still free of the “Toxic Trio”, it is also free of formaldehyde resin and camphor.
In addition to 3 Free and 5 Free, many companies are increasing the number of chemicals they are removing. Our polishes are 7 free. This means that they are free of ethyl tosylamide and xylene.
The number of ingredients that nail polishes tend to claim to be free of keeps on climbing. Currently there are also 8 free products and 9 Free products. However, while accurate in a way, these ingredients are often ones that are not typically used in nail polishes anymore or that pose no real harm to the user.