For many years, parabens were considered safe preservatives with low systemic toxicity. Due to their broad spectrum antimicrobial activity they are used in many cosmetic, food and pharmaceutical products. Parabens are alkyl hydroxy benzoate preservatives (namely methyl-paraben, ethyl-paraben, propyl-paraben, and butyl-paraben). Parabens are permitted as preservatives in food up to 0.1%. In cosmetics they are permitted in concentrations of up to 1%.
Recently the safety of parabens has been in question. Currently, there is evidence of the endocrine disrupting effects of these preservatives because they are estrogen mimics (xenoestrogens) which bind to your cells estrogen receptor sites. Parabens are easily absorbed through your skin and can be stored in your body's tissues. When parabens enter your body they affect your hormonal system by mimicking estrogen and promoting cellular growth in breast tissue. Subsequently parabens have been linked to breast cancer tumors.