This is part 2 involving the potential dangers of antiperspirants. Again, the main culprit appears to be aluminum, although parabens (commonly found in deodorants) have also been found to play a possible role in breast cancer. Parabens are synthetic antimicrobial preservatives used in a wide array of cosmetics and even as food additives.
An article in the European Journal of Cancer Prevention by Kris McGrath in 2003 ("An Earlier Age of Breast Cancer Diagnosis Related to More Frequent Use of Antiperspirants/Deodorants and Underarm Shaving": 479-85) studied age at time of breast cancer diagnosis in relation to how long the patient had been shaving and using antiperspirants/deodorants. As stated in the journal, "in conclusion, underarm shaving with antiperspirant/deodorant use may play a role in breast cancer. It is not clear which of these components are involved. Reviewed literature insinuates absorption of aluminium salts facilitated by dermal barrier disruption."
Again, no true causal link could be definitively established, but the end conclusion is that there is most likely some nexus between breast cancer and use of antiperspirants/deodorants and underarm shaving. The role of shaving in this process is that it alters the normal barrier of the skin, possibly making absorption of aluminum and/or parabens easier or greater than normal.
Philippa Darbre also more recently published an article in the same journal that shows experimental links, stating "evidence shows that at these tissue concentrations, aluminium has the potential to adversely influence breast epithelial cells and the breast microenvironment leading to alterations associated with carcinogenesis, progression and metastasis" ("Aluminum and breast cancer: Sources of exposure, tissue measurements and mechanics of toxicological actions on breast biology." European Journal of Cancer Prevention (Nov. 2013): 257-61; http://www.ncbi.nlm.nih.gov/pubmed/ 23899626).
This same researcher also published an article years earlier that stated "the strongest supporting evidence comes from unexplained clinical observations showing a disproportionately high incidence of breast cancer in the upper outer quadrant of the breast, just the local area to which these cosmetics are applied. A biological basis for breast carcinogenesis could result from the ability of the various constituent chemicals to bind to DNA and to promote growth of the damaged cells" (Darbre, P. "Underarm cosmetics and breast cancer." Journal of Applied Toxicology 23, No. 2 (2003): 89-95; http://www.ncbi.nlm.nih.gov/pubmed/12666152).
An author I mentioned previously in regards to his research on aluminum and Alzheimer's Disease has also extensively studied aluminum and breast cancer. In 2007, Christopher Exley published a study titled "Aluminum in human breast tissue", finding confirmation of "the presence of aluminium in breast tissue and its possible regional distribution within the breast. Higher content of aluminium in the outer breast might be explained by this region’s closer proximity to the underarm where the highest density of application of antiperspirant could be assumed." He notes that the upper outer quadrant, the breast area closest to the underarm, consistently showed higher aluminum levels than other quadrants. Although this does not prove that aluminum is the cause, it should make us all think more about our exposures. This study goes on to say that "aluminium is a metalloestrogen, it is genotoxic, is bound by DNA and has been shown to be carcinogenic. It is also a pro-oxidant and this unusual property might provide a mechanistic basis for any putative carcinogenicity. The confirmed presence of aluminium in breast tissue biopsies highlights its potential as a possible factor in the aetiology of breast cancer” (Journal of Inorganic Biochemistry 101(9) (2007): 1344-6; http://www.ncbi.nlm.nih.gov/pubmed/17629949).
Some of these same authors have looked at the effects of parabens as well - Darbre published an article called "Concentrations of Parabens in Human Beast Tumours" in which she notes that parabens can bind to estrogen receptors and can effectively increase the growth of MCF7 human breast cancer cells (Journal of Applied Toxicology 24 (2004): 5-13; http://www.ncbi.nlm.nih.gov/pubmed/14745841). Here are links to related articles:
- http://www.ncbi.nlm.nih.gov/pubmed/12975767
- http://www.ncbi.nlm.nih.gov/pubmed/18484575
- http://europepmc.org/abstract/MED/21155623
Again, I am in no way implying that there is data supporting a direct link between breast cancer (and Alzheimer's) and aluminum from antiperspirants. What I am trying to show is that there is growing evidence suggesting a link. My thinking is that even a potential cause and effect relationship is worth being aware of, and possibly worth taking action against. In the next blog entry I will conclude with some of those actions that are worth investigating.