Parabens are a group of chemicals that have been widely used as preservatives in many cosmetics and hair products to ensure the products remain free of bacteria, fungus and other microbes. They also help extend the shelf life of cosmetic products. In 1998, the United States Environmental Protection Agency released a report stating that parabens – butyl, ethyl, methyl and propyl varieties – demonstrated “estrogenic activity.”
This means that these chemicals could possibly imitate hormones found in the human body and have an adverse effect on our endocrine system when absorbed by the skin or flushed into our drinking supply.  Further studies have indicated that the level of parabens in topical ingredients is very low and are safe for use. Alternative preservatives to parabens are available and are offered in many cosmetic products.