By: Dr. Christina Mossaad and Mrs. Vanessa Ralph, M.S. Pharmaceutical Chemistry
The claim of “Paraben-free” is as common to cosmetics as “BPA-free” is to plastic food ware. As we hear these claims often, it is important to know of parabens and their significance. First lets explore their structure, where they are commonly found, why there is concern surrounding them in the media, and the mechanism(s) by which they affect the human body.
What are parabens?
Structurally, parabens are a series of parahydroxybenzoates (hydroxybenzoic acids in which the bonds are para, or on either side, of the benzene structure). Parabens act as effective preservatives in many formulas containing water. Thus, they are used to extend the shelf life of aqueous compound products (most commonly cosmetics).
Shown in the images above, paraben (left) is structurally similar enough to estradiol (a derivative of the hormone estrogen shown right). This is the most prominent concern for researchers assessing the potential toxicity of parabens. Estrogen receptors (ER) have delicate mechanisms in place to alter the genetics associated with squamous cellular growth, various metabolic processes, and, if accumulated, can play a role in oxidative stress.
Upon the dissection of breast and other squamous cell cancers, parabens and other estrogen receptor activators (ligands) can be found amassed within the tumors. Although no direct link between parabens and breast cancer have, as of now, been scientifically documented, the accumulation of these substances around and within tumors is what is stirring cause for concern.
Where can Parabens be found?
Parabens can be derived from a plant source, but are more often produced synthetically via the Fisher Esterification mechanism involving para-hydroxybenzoic acid and propanol (an alcohol). The most common are methylparaben, propylparaben, ethylparaben, and butylparaben varying the number of carbon chains.
Parabens are often found in various shampoos, conditioners, lotions, shaving gels, lubricants, spray tanning, sanitary products, toothpaste, and other cosmetics. As many of these products are externally applied, there is much research to confirm that human skin does absorb and retain trace amounts of parabens upon exposure.
Scientific Review of the Potential Risks concerning Paraben Exposure…
According to multiple research papers in increasing numbers, parabens are endocrine disruptors and warrant further investigation into their role in breast tissue accumulation and tumor growth. They have also been found to be chemoresistant in some individuals, complicating the treatment of progressive breast cancer.
Studies have been slowly working towards illuminating why parabens are found within tumors, how they are absorbed and retained in the skin, and whether or not this directly leads to increased rates of breast cancer. A study just published by Lillo et. al. (2017) found methylparaben stimulates tumor cells in estrogen responsive breast cancer models.
Investigation and discovery will continually be evaluated until the mechanisms and underlying principles are clearly defined. In the meantime, evaluate what products you are currently using regularly, and take care, as the use and accumulation of parabens is additive (it appears as though parabens have no natural exit from the human body and thus accumulate). Educate and inform yourself as to the contents of your products and do what you can to minimize exposure.
Please note, some companies have resorted to listing parabens as an ingredient under their less commonly known name of: alkyl parahydroxy benzoates.
Alternatives to Parabens, what to look for in your cosmetics…
- T-50 Vitamin E oil is an antioxidant as well as a healthy skin augmentation
- Grapefruit Seed Extract (GSE) is an antimicrobial commonly blended with vegetable glycerin for a non-irritating delivery
In regards to LipSense Gloss and Color…
You will note that LipSense colors are in fact, paraben-free. Yet, the glosses used to set the color and hydrate the lips do contain “propylparaben”.
This excerpt is from our detailed blog post on the ingredients found in LipSense’s gloss.
INGREDIENT #9: Propylparaben
All research suggests it is a non-toxic, non-irritant when used in 0.5-1% concentrations (the gloss contains a fraction of this percent). Thus the exposure is minute but still worth assessing.
Read more about the ingredients comprising LipSense gloss here.
Take care in the substances you place on your skin and the skin of those in your care. While minute exposures are unavoidable and while it is impossible to know the potential effects of your personal biochemical make-up with every potential ingredient known to man, you should do what you can to minimize exposure.
Ensure to do breast exams regularly and speak to your healthcare provider about testing for precursors or genetic markers that could influence your risk and likelihood of breast cancer development. Best of luck out there ladies!
Please comment below as to what you would like for us to explore next!
Resources and References:
- Lillo et. al. https://www.ncbi.nlm.nih.gov/pubmed/27581495 (2017)
- Podcast “How make-up works” by Stuff You Should Know.
- Darbre and Harvey http://onlinelibrary.wiley.com/doi/10.1002/jat.1358/full (2008)
- Berkeley News release http://news.berkeley.edu/2015/10/27/lotion-ingredient-paraben-may-be-more-potent-carcinogen-than-thought/ (2015)
- Qianhui Mao, Feng Ji, Wei Wang, Qiquan Wang, Zhenhu Hu, Shoujun Yuan, Chlorination of parabens: reaction kinetics and transformation product identification, Environmental Science and Pollution Research, 2016, 23, 22, 23081 https://link.springer.com/article/10.1007%2Fs11356-016-7499-y
- Hitomi Ozaki, Kazumi Sugihara, Yoko Watanabe, Shigeru Ohta, Shigeyuki Kitamura, Cytochrome P450-inhibitory activity of parabens and phthalates used in consumer products, The Journal of Toxicological Sciences, 2016, 41, 4, 551
- http://www.ewg.org/enviroblog/2015/07/myth-natural-parabens Widespread environmental parabens is a myth
- http://pubs.rsc.org/en/content/articlelanding/2016/ew/c5ew00240k#!divAbstract Parabens in urban rivers as a pollutant from water runoff.
- http://www.nature.com/jes/journal/vaop/ncurrent/full/jes201633a.html Skin Permeability of Parabens