16 January, 2017
Cosmetics. Everyone uses them, women and men alike. Cosmetics include many different materials with various roles that determine the activity, texture, color and smell of the final product. People are not aware of the fact that, unlike medications, cosmetics are not tested as rigorously by the regulatory authorities and the included chemicals may be harmful. The external placement and targets for use should not distract us from investigating potential systemic ill-effects. For example, ingredients in cosmetics may have an effect on a variety of hormonal pathways. A recent review, which analyzed possible associations with age at menopause, concluded that there is lack of data on the relevant risk outcomes of cosmetic use .
A review of the ingredients in the best-selling and top-rated products of the top beauty brands in the world, as well as a review of highlighted chemicals by non-profit environmental organizations, revealed 11 chemicals and chemical families of concern: butylated hydroxyanisole/butylated hydroxytoluene, coal tar dyes, diethanolamine, formaldehyde-releasing preservatives, parabens, phthalates, 1,4-dioxane, polycyclic aromatic hydrocarbons, siloxanes, talc/asbestos, and triclosan . A previous review pointed at the same problematic chemicals and expressed concerns that, despite laboratory and animal incriminating findings, studies in humans have rarely been done and therefore there is no clear proof for harm . Of interest, parabens exhibit very weak estrogenic activity in vitro and in vivo, but evidence of paraben-induced developmental and reproductive toxicity in vivo lacks consistency and physiological coherence. Evidence attempting to link paraben exposure with human breast cancer is non-existent. Still, a study from Japan demonstrated a negative association between estrogen-equivalent total paraben (odds ratio 0.73, 95% confidence interval 0.56–0.96) and butyl paraben concentrations (odds ratio 0.83, 95% confidence interval 0.70–0.99) and menstrual cycle length . Phthalates (plasticizers) are industrial contaminants which are endocrine disruptors and may affect reproductive health and pregnancy . Phthalates are almost ubiquitous in personal care products such as perfumes, cosmetics, moisturizer, nail polish, liquid soaps, and hair spray. These chemicals are sometimes added intentionally as a solvent and a fixative. In fact, examination of 47 branded perfumes showed untoward exposure to phthalates through the skin in almost all of them . Another aspect related to cosmetics is environmental contamination. A survey identified ten potential harmful chemicals: polydimethylsiloxane, butylated hydroxylanisole (BHA), butylated hydroxytoluene, triclosan, nano titanium dioxide, nano zinc oxide, butylparaben, diethyl phthalate, octinoxate methoxycinnamate and benzophenone . Skin care products had the highest quantities of chemicals of concern, with titanium dioxide and zinc oxide nanomaterials being dominant potential contaminants.
Another interesting aspect of potential harm relates to molecules with estrogen-mimicking properties and breast cancer risk. The breast may be exposed to a range of estrogenic chemicals applied as cosmetics to the underarm and breast area . These cosmetics are left on the skin allowing a more direct dermal absorption route for breast exposure to estrogenic chemicals.
The modern world makes our life better in many ways, but there is a clear health-related tag-price which we usually overlook. Contamination of our environment, mainly the result of air pollution and toxic chemicals, seems to be a problem that cannot be solved. However, data are accumulating in regard to individual exposure to cosmetics of all sorts that might be sources for serious adverse health consequences. Proper awareness, education and implementation of defensive strategies to minimize exposure and contamination might change these personal risks.
Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
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