Parabens were found in breast milk and breast cancer tumors. In a 2004 study, tests found parabens in breast cancer tumors in nineteen out of twenty women with breast cancer. This study, while small and statistically insignificant, proves the ability of paraben preservatives to penetrate skin and accumulate in living tissue, such as breasts. In the body, parabens mimic our own hormones and can have an endocrine-disrupting action.
British molecular biologist Philippa Darbre reported that found in breast cancer tumors came from something applied to the skin, such as an antiperspirant, cream or body spray. This could explain why up to 60% of all breast tumors are found in just one-fifth of the breast – the upper-outer quadrant, nearest the underarm.
“The presence of intact paraben esters in human body tissues has now been confirmed by independent measurements in human urine, ” writes Dr. Darbre, “The ability of parabens to penetrate human skin intact without breakdown by esterases and to be absorbed systemically has been demonstrated through studies not only in vitro but also in vivo using healthy human subjects.” In addition, the parabens have now also been shown to possess androgen antagonist activity, to act as inhibitors of sulfotransferase enzymes and to possess genotoxic activity.
A 2004 study at Northwestern University found that breast cancer now affects younger women which could be related to more frequent use of antiperspirants with aluminum and underarm shaving. “I personally feel there is a very strong correlation between the underarm hygiene habits and breast cancer,” said immunologist Dr. Kris McGrath.
The American Cancer Society stated that “larger studies are needed to find out what effect, if any, parabens might have on breast cancer risk.”
One of the recent studies in June 2011, found that parabens not only act as hormone mimickers in breast cancer, but also trigger the genes that are involved in breast cancer formation. Korean scientists from Chungbuk National University investigated the xenoestrogenic activity of a panel of parabens (methyl-, ethyl-, propyl-, isopropyl-, butyl-, and isobutylparabens) in animal pituitary cancer cell line. Following the treatment, they found a significant increase in estrogenic biomarker gene – Calbindin-D. Interestingly, co-treatment with fulvestrant, a pure antiestrogen largely reversed the paraben-dependent induction of estrogenic biomarker gene. These results indicate that estrogenic biomarker gene is induced by parabens.
With the continued use of parabens in the majority of mainstream cosmetics, there is a need to carry out detailed evaluation of the potential for parabens to increase female breast cancer incidence, to interfere with male reproductive functions and to influence development of malignant melanoma which has also recently been shown to be influenced by estrogenic stimulation.
