Nail polish is one of the few cosmetics that almost no one looks at the ingredients of. We look at the INCI of a €20 cream and then paint our nails with anything. We see it daily in the pharmacy, so this guide is about that: what conventional polishes contain, what "non-toxic" or "12-free" labels really mean, and how to distinguish marketing from the formula.
What's hidden in conventional nail polish
The classic nail polish formula is lacquer chemistry: solvents, resins, and plasticizers derived from petroleum. The names that clean brands remove first will sound familiar from reading labels: toluene (solvent), formaldehyde and its resins (hardener), dibutyl phthalate (DBP) (plasticizer), and camphor. You don't need to memorize them: just know that they are the reason why an entire category of reformulated polishes exists.
What "X-free" means
"5-free," "9-free," or "12-free" is an industry convention: the number indicates how many controversial ingredients the formula has eliminated compared to conventional polish. A 5-free removes the five classics (the four above plus formaldehyde resins); from there, each step adds exclusions: synthetic fragrances, parabens, xylene, or animal-derived ingredients. A 12-free is, for now, at the high end of the requirement.
Two honest caveats, because there's marketing here too: "X-free" is not an official regulated seal, so two brands can count the list differently. And just because a polish is 12-free doesn't make it edible: it's still a lacquer. It means they've removed the ingredients with the worst records, not that it's rose water.
Bio-based: the other half of the story
Removing is half the work; the other half is what it's replaced with. Bio-based polishes replace part of the petrochemicals with plant biomass —in the formulas we work with, derived from potato, corn, cassava, and cotton— reaching up to 84% bio-based percentages. The practical result: same shine and coverage, much less harsh chemicals, and removal with acetone-free nail polish remover.
"Vegan" and "natural" are not the same
Vegan means without animal-derived ingredients —watch out for carmine in reds and guanine in pearlescent, which are common stowaways—. Natural or bio-based refers to the plant origin of the formula. A polish can be vegan and petrochemical at the same time. Those that meet both are the small intersection, and that's what we look for when choosing our catalog.
How to choose without going crazy
Our pharmacy rule in three steps: look for the number of "frees" and make sure the brand specifies them (if it doesn't say which ones, be suspicious); check if it declares the bio-based percentage, which is the hard data to fake; and verify how it's removed, because a clean formula that requires acetone and filing takes away with one hand what it gives with the other.
In our selection, the brand that meets the full standard —12-free, vegan, and 84% bio-based— is the one you'll find in the green nail polishes collection. If you want to know more about it, here is the complete brand guide. And if you're coming to this article with nails damaged by semi-permanent polish, it's best to start with how to remove it without damaging your nails and recover them.
Frequently Asked Questions
Do "non-toxic" polishes work just as well?
Current bio-based formulas offer shine and coverage comparable to conventional polish. Where there may be a difference is in extreme durability: a salon semi-permanent lasts longer, at the cost of a much more aggressive removal.
Is "non-toxic" an official seal?
No. Neither "non-toxic" nor "X-free" are regulated as seals. That's why it's advisable for the brand to detail exactly what it excludes and what percentage of the formula is bio-based.
What nail polish remover goes with these polishes?
An acetone-free one. Bio-based formulas are easily removed, so you don't need a strong solvent, and your nails and cuticles will appreciate it.
Is a 12-free polish suitable for fragile nails?
It's the gentlest option, and even so, a fragile nail would rather have a hardening treatment base and a few days of rest than any color. First the nail, then the polish.
This article is for informational purposes only and does not replace the advice of a healthcare professional.