What is "paraben"

n. Any of a group of chemicals used as preservatives in cosmetics and pharmaceuticals, wherein the hydrogen of a parahydroxybenzene molecule is replaced by an alkyl group

Parabens are a class of widely used preservatives in cosmetic and pharmaceutical products. Chemically, they are a series of parahydroxybenzoates or esters of parahydroxybenzoic acid (also known as 4-hydroxybenzoic acid). Parabens are effective preservatives in many types of formulas. These compounds, and their salts, are used primarily for their bactericidal and fungicidal properties. They can be found in shampoos, commercial moisturizers, shaving gels, personal lubricants, topical/ parenteral pharmaceuticals, spray tanning solution, makeup, and toothpaste. They are also used as food additives.

Their efficacy as preservatives, in combination with their low cost, the long history of their use, and the inefficacy of some natural alternatives like grapefruit seed extract (GSE), probably explains why parabens are so commonplace. No effective direct links between parabens and cancer have been established.