Who regulates cosmetics in the United States? NO ONE. In 1938 the cosmetic industry was granted self-regulation. Nothing has changed since 1938. The FDA isn't even authorized to approve cosmetic ingredients. The U.S. Federal Government doesn't require health studies or pre-market testing on personal care products. Manufacturers are free to use almost any ingredient they choose. As a result, we are exposed to thousands of harmful chemicals that are banned in other countries.
So what can you do?
Read labels - you can't bank on the what the bottle says. Unfortunately in this country, we have issues with label laws too. If a product has one natural ingredient, added to 10 chemicals, they are legally allowed to label the bottle as "all natural". Be sure to always read the label and read every ingredient.
Familiarize yourself with chemicals - you need to know what chemicals to stay away from. Refer to the Dirty Dozen list that highlights the 12 most common toxic & carcinogenic compounds found in cosmetics.
Take advantage of EWG - Environmental Networking Group is a non-profit, non-partisan organization dedicated to protecting human health and the environment. If you click on the EWG Verified tab, they review thousands of personal care products and give their approval on products that meet their strict standards.