Nail polishes have previously been bashed for containing harmful chemicals linked to tons of health problems. It’s one simple way of ruining the simple pleasures of life- getting a manicure and pedicure because they tend to be oh-so-relaxing.

However, a new study sheds light on the fact that nail polish manufacturers may not be completely open to you despite what the labels say. Such compounds contained in nail polishes correspond with health concerns such as thyroid dysfunction, allergic reactions, obesity, cancer, and birth defects.

Due to the concerns raised about such chemicals in the past, nail polish manufacturers started labeling their products as 3-free. This means that the nail polish does not contain the three chief harm-causing chemicals, toluene, dibutyl phthalate (DnBP), and formaldehyde.

The “3-free” practice commenced about a decade ago. In the present time, manufacturers also label their nail polishes as “5-free” this means that in addition to the trio of toxic ingredients, the product does not contain two more harmful chemicals knowns as camphor and formaldehyde resin that are potential allergens.

Others have started to claim that their nail polishes are “6-free” and the practice goes on until “13-free.” However, the researchers of this study point out that this is where the issue surfaces.

The researchers examined 55 polishes from 44 popular brands that were sold in nail salons and stores. They compared the labels and ingredient lists, tallying what they claimed as free from toxic ingredients.

The researchers concluded that as long as the nail polish was labeled “3-free” it stuck to its promise. However, as the rating increased beyond “5-free,” the consistency of the composition started to vary. In other words, they were less likely to be truly free of the toxins that they claimed that they did not contain.

Therefore, the next time you decide to get your nails done, pay close attention to their ingredient list while keeping in mind the findings of this study. After all, it is better to be safe than to be sorry.