When it comes to chemicals in your cosmetics, nail polishes can be some of the worst offenders. So when you can, opt for polishes that don't have ingredients like formaldehyde and toluene.
Here are some brands to look for:
Scotch Naturals, $15 per bottle
Zoya nail polish, $8 per bottle
SpaRitual Nail Polish, $5 for the mini bottle, $10 for the regular size