ROKer Roosa asked for my take on the harmful effects of Parabens, something I’ve been curious about my self, and I’m more than happy to have a closer look at. There’s been a lot of focus on parabens in cosmetics lately.
These compounds, and their salts, are used primarily for their bactericidal and fungicidal properties. They can be found in shampoos, commercial moisturizers, shaving gels, personal lubricants, topical/parenteral pharmaceuticals, spray tanning solution, makeup,and toothpaste. They are also used as food additives.
For simplicities sake, I’ll do it this way:
1.Parabens and pregnancy: So far, parabens have only been associated to decreased male reproductive function in rat offspring, after mothers were exposed to parabens. This is due to the mild estrogen like effects of parabens. There has not been any study to claim that parabens exert any other adverse consequences on fetal development.
2. Parabens and cancer: This is perhaps the most feared aspect of parabens, much due to a study published in 2004 (Darbre, in the Journal of Applied Toxicology), which detected small quanteties of parabens in breast tumors. The study discussed this information in the context of the weak estrogen-like properties of parabens and the influence of estrogen on breast cancer. Estrogen, and synthetic chemicals that act like estrogen, play a role in stimulating the division of breast cells and affect other hormones that stimulate breast cell division. Your body does not easily break down synthetic estrogen, and it can accumulate in fat cells, including breast tissue. However, the study left several questions unanswered. For example, the study did not show that parabens cause cancer, or that they are harmful in any way, and the study did not look at possible paraben levels in normal tissue. Although parabens can act similarly to estrogen, they have been shown to have much less estrogenic activity than the body’s naturally occurring estrogen. For example, a 1998 study (Routledge et al., in Toxicology and Applied Pharmacology) found that the most potent paraben tested in the study, butylparaben, showed from 10,000- to 100,000-fold less activity than naturally occurring estradiol (a form of estrogen). Further, parabens are used at very low levels in cosmetics. In a review of the estrogenic activity of parabens, (Golden et al., in Critical Reviews in Toxicology, 2005) the author concluded that based on maximum daily exposure estimates, it was implausible that parabens could increase the risk associated with exposure to estrogenic chemicals. An alternative mechanism by which parabens can indirectly affect estrogen levels is via inhibition of sulfotransferase activity inside the human skin cells. By blocking sulfotransferases, the estrogen levels can remain higher than normal. If this same action occurs in breast tissue, then these compounds may be linked to increased rates of breast cancer.
3. Parabens, hormones and sperm quality: Due to the mild estrogen mimicry effect of parabens, there is evidence for decreased male sex-hormone levels (testosterone) in rats, as well as decreased sperm counts, and daily production. Testosterone decreased in a dose dependent manner related to paraben concentration. Parabens have also been suggested as endocrine disruptors which can lead to early puberty in adolescent girls and boys, as reported by the New York Times. In a recent study, levels of parabens detected in urine samples from males were positively associated to sperm DNA damage. Paraben’s effect on mitochondrial function has been proposed as another mechanism for their possible role in male infertility.
4. Parabens and toxicity: Studies on the acute, subchronic, and chronic effects in rodents indicate that parabens are practically non-toxic. Parabens are rapidly absorbed, metabolized, and excreted.
5. Parabens and allergy: In individuals with normal skin, parabens are, for the most part, non-irritating and non-sensitizing. Parabens can, however, cause skin irritation and contact dermatitis and rosacea in individuals with paraben allergies, a small percentage of the general population.
6. Parabens and sun-exposure: Studies indicate that methylparaben applied on the skin may react with UVB leading to increased skin aging and DNA damage.
When it comes to my personal approach to parabens, I’m of the opinion that it’s not something I need to be overly worried about at this time in my life. The concentrations of parabens used in cosmetics, is much less than those shown to have adverse effects in research so far. I will (and have previously) opted for organic and paraben free body-moisturizers as the surface area covered by such a product exceeds that of my face, but when I at one point decide to reproduce, and form my little army of mini-me’s, I will switch most, if not all my skincare products to paraben-free brands, just for the sake of inner peace. As mentioned under point 1 the estrogen activity of parabens might (stress on the might here) influence the reproductivity of my unborn male child! And that’s not something I’d like to be responsible for. Also, as parabens have been associated to UVB sensitization, a paraben free sunscreen may be something to consider. Lastly, if I were a man, I would worry more about parabens in skincare products, as a recent study established a link between paraben levels in male urine and DNA damage of sperm. Also not all parabens are equally worrisome, I will have a look out for products containing isobutyl-paraben or butyl-paraben and perhaps pass by those, as they are associated to higher estrogen- like activity. Methyl and Ethyl parabens have the least.
But, that’s just what I would do. How you choose to approach parabens in cosmetics is up to you. And as I see it, there’s no need to pull your hair out about them just yet.
Urinary Concentrations of Parabens and Serum Hormone Levels, Semen Quality Parameters, and Sperm DNA Damage
John D. Meeker,1 Tiffany Yang,1 Xiaoyun Ye,2 Antonia M. Calafat,2 and Russ Hauser3,4
Environ Health Perspect. 2011 February; 119(2): 252–257.
Published online 2010 September 28. doi: 10.1289/ehp.1002238
The use of deodorants/antiperspirants does not constitute a risk factor for breast cancer
Author(s) : Moïse Namer, Elisabeth Luporsi, Joseph Gligorov, François Lokiec, Marc Spielmann Bulletin du Cancer. Volume 95, Number 9, 871-80, septembre 2008, synthèse
Antiandrogenic properties of parabens and other phenolic containing small molecules in personal care products
Jiangang Chen,1 Ki Chang Ahn,2 Nancy A. Gee,1,3 Shirley J. Gee,2 Bruce D. Hammock,2,4 and Bill L. Lasley1,3
Toxicol Appl Pharmacol. Author manuscript; available in PMC 2008 June 15.
Published in final edited form as:
Toxicol Appl Pharmacol. 2007 June 15; 221(3): 278–284.
Published online 2007 March 27. doi: 10.1016/j.taap.2007.03.015
U. S. Food and Drug Administration March 24, 2006; Updated October 31, 2007
Methylparaben potentiates UV-induced damage of skin keratinocytes
- Osamu Handaa,
- Satoshi Kokuraa, , ,
- Satoko Adachib,
- Tomohisa Takagia,
- Yuji Naitoc,
- Toru Tanigawae,
- Norimasa Yoshidad,
- Toshikazu Yoshikawab
- Volume 227, Issues 1–2, 3 October 2006, Pages 62–72
Safety assessment of esters of p-hydroxybenzoic acid (parabens)
- M.G. Sonia, , ,
- I.G. Carabinb,
- G.A. Burdockc
- Food and Chemical Toxicology
- Volume 43, Issue 7, July 2005, Pages 985–1015
Decreased Sperm Number and Motile Activity on the F1 Offspring Maternally Exposed to Butyl p-Hydroxybenzoic Acid (Butyl Paraben)
Kyung-Sun KANG1), Jeong-Hwan CHE1), Doug-Young RYU2), Tae-Won KIM1), Guang-Xun LI1), Yong-Soon LEE1)
1) Department of Veterinary Public Health, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University 2) Department of Environmental Health, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University
Effects of butylparaben on the male reproductive system in rats
- Shinshi Oishi
doi: 10.1191/0748233701th093oa Toxicol Ind Health February 2001 vol. 17 no. 1 31-39
Toxic Effects of the Easily Avoidable Phthalates and Parabens
Walter J. Crinnion, ND