Currently, Scotch Naturals is my current go-to for completely eco-friendly and non-toxic nail polish. While there are lots of fantastic non-toxic brands out there, Scotch's water-based formula isn't objectionable in the least, and they really seem to get what's going on with color trends.
I'm always on the hunt for any other brands I can add to my repertoire, and I think I've found one in Parisian brand Kure Bazaar!
The formula is 4-free, rather than the now standard 3-free (no formaldehyde - a known carcinogen, and no DBP or toluene - known reproductive disruptors), which means it also excludes camphor (an eye, nose, and throat irritant). Plus, up to 85% of the ingredients (depending on the color) come from natural sources including wood pulp, wheat, cotton, potatoes and corn.
They generously sent me a bottle of Mon Bleu to try, and it's fantastic.
I'll definitely be purchasing more Kure Bazaar this year. It's not cheap ($16 a pop), but the exclusion of those nasty chemicals is so worth it.
Here's their entire line - what colors strike your fancy?