Once a luxury item, nail polish is a part of the daily cosmetic routine for many. But some of the chemicals used to create modern nail polish are toxic. Learn what ingredients to avoid and which brands omit them from their lineup. Even if your nail care products are labeled nontoxic, apply them only in well-ventilated areas, and don't inhale the fumes.

Methods of nail coloring can be documented throughout the history of cosmetics. The wealthier ancient Egyptians probably dyed their fingernails with henna. But today's nail lacquer is almost entirely a 20th century invention.

Modern nail polish consists of four basic ingredients. Nitrocellulose, or cellulose nitrate, is the basic viscous film-forming agent. Resins and plasticizers are added to improve flexibility. Pigments and other coloring agents complete the rainbow of available nail polish colors. And solvents contain the coloring agents until you brush on the polish and allow it to dry.

Twentieth century improvements to nail-coloring methods come with a price. The solvents and plasticizers in nail polish are often toxic. Ingredients of special concern include toluene, butyl acetate, ethyl acetate and dibutyl phthalate. They won't hurt you once they're on your nails, but if ingested or inhaled they can make you very sick or even kill you.

Dibutyl phthalate, or DBP, has been "linked to cancer in lab animals, and underdeveloped genitals and other long-term fertility problems in newborn boys," according to a "Pittsburgh Post-Gazette" article. The article quotes Stacy Malkan of the Campaign for Safe Cosmetics, who expresses concern especially for nail salon workers. Not only do they inhale fumes all day long, but there's often no way to know what level of toxins they are exposed to. Nail polish for use in salons is exempt from laws requiring ingredients to be listed.

DBP has not been conclusively proved to be harmful, and several groups are pushing back against its growing reputation. Nevertheless, the European Union has banned DBP from personal care products sold in Europe. No such bans exist in the United States, but some salons are voluntarily removing DBP-bearing products from their shelves.

The National Healthy Nail Salon Alliance maintains a list of nail polishes you can buy that are free of the "toxic trio" of toluene, DBP and formaldehyde. It provides a list formatted to fit in your wallet.