Substance used in cosmetics to prevent contamination of products, particularly water-based formulas. Although there’s definitely a risk of aggravation from these types of ingredients, the risk to skin and eyes from using a contaminated product is considered by many scientists to be even greater.

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About the Experts

Paula Begoun is the best-selling author of 20 books about skincare and makeup. She is known worldwide as The Cosmetics Cop and creator of Paula’s Choice Skincare. Paula’s expertise has led to hundreds of appearances on national and international radio, print, and television including:

The Paula's Choice Research Team is dedicated to busting beauty myths and providing expert advice that solves your skincare frustrations so you can have the best skin of your life!