Here is a quote:
<<WebMD also recommends contacting a physician before using nail polish during pregnancy. This is probably because many brands of nail polish, including products by L'Oreal, Maybelline, Oil of Olay and CoverGirl, include a hormone disrupter known as dibutyl phthalate (or DBP). According to the Environmental Working Group, DBP has been found to cause birth defects in lab animals, particularly male offspring, including "testicular atrophy, reduced sperm count, and defects in the structure of the penis."
A study by researchers at the Centers for Disease Control (CDC) reported that every single one of the 289 people they tested came up positive for having DBP in their bodies. Scientists speculate that this chemical, which stores in your body fat and can be passed through breast milk, is getting into people's bodies through common beauty aides. Women who are pregnant, nursing or who are considering having children in the future should carefully avoid all products that list phthalates in the ingredients.
Many nail polishes also contain a known carcinogen called formaldehyde. Formaldehyde is most commonly recognized for its use in embalming, but is also common in many household products. People working in nail saloons may have particular cause to be worried about this chemical because of their high rate of exposure to it. Luckily, some formaldehyde-free nail polishes can be found, if people know to look for them.>>
I can't even start to read about all the chemicals that are found in people's bodies these days, especially pregnant/nursing women and children. It is enough to make anyone paranoid. I just try to avoid the obvious things. Besides, being a SAHM with a two year old, I need short nails anyway, and I just don't see much point to painting them. But, that was never a huge thing for me. Going without highlighting my hair bugs me more, but I've gotten used to it.