Substance used in cosmetics to prevent bacterial and microbial contamination of products, particularly water-based formulas. Although there’s definitely a risk of irritation 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. [1]

References Cited:

  1. Lundov M, Moesby L, Zachariae C, Johansen J. Contamination versus preservation of cosmetics: a review on legislation; usage; infections; and contact allergy. Contact Dermatitis. 2009;60(2):70-8.

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Paula Begoun is the best-selling author of 20 books on skin care and makeup. She is known worldwide as the Cosmetics Cop and creator of Paula's Choice. Paula's expertise has led to hundreds of appearances on national and international television including:

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