Millions of women use mascara to make their lashes lush. It's been around since the 19th century, and those tubes and wands are still making eyes more alluring.
Here's a look at what's inside the tube.
Mascara's ingredients typically include a carbon black or iron oxide pigment to darken lashes; a polymer to form a film that coats lashes; a preservative; and thickening waxes or oils such as lanolin, mineral oil, paraffin, petrolatum, castor oil, carnauba wax, and candelilla wax.
There are two basic choices: formulas with no water, or emulsions of water and oil. The no-water formulas tend to be waterproof and less likely to smudge or flake. But they can be difficult to remove. Emulsions are easier on lashes but may flake or smudge.
In the 1930s, lash darkeners contained scary ingredients such as turpentine, lead-containing kohl, and aniline, a hair-dye ingredient, all of which left more than one woman blind. Now regulations strictly limit the ingredients to those that are safe to apply in the eye area, but you should be on the lookout for thimerosal, a preservative that can cause conjunctivitis and eyelid dermatitis (a rash). Thimerosal is still used in some mascaras.
To find out if your mascara will flake or run, check how much water it contains. The lower water is on the ingredients list, the less likely you'll get smeared.
Still, experts suggest limiting your use of waterproof, smudge proof formulas made with little to no water. The extra effort needed to remove these products can damage lashes, causing them to break or fall out.