By Rachel Chan
The clean beauty movement has gained a tremendous amount of traction in recent years. Labelling products as “clean” has become a common marketing tool. Several big names in skincare have played along- there’s even a “Clean at Sephora” label to differentiate these products. The idea behind clean beauty is to formulate products without ingredients shown or suspected to harm human health. Clean beauty has a spirited dislike for certain synthetic chemicals commonly used in skincare. Advocate groups, such as the Environmental Working Groups (EWG) and the Campaign for Safe Cosmetics, have compiled long lists of these ingredients. Amongst many demonised ingredients, one of clean beauty’s main villains is parabens. This article explores whether formulating without such ingredients is justified and whether the alternatives are any better.
Parabens are a group of esterified hydroxybenzoic acid compounds that are used as preservatives in skincare. The most common parabens are methyl-, ethyl-, propyl- and butyl- parabens. They’ve been used since the 1920s and today are present in around 85% of cosmetics,andforgoodreason(Seo, Kim and Kim,2016). Parabens are economical and effective antimicrobial agents even at low concentrations (most products only contain up to 0.3% of parabens). They’re also fairly well-regulated: the EU Commission has limited the total parabens in cosmetic formulas to 0.8% (Seo, Kim and Kim, 2016). Due to a lack of data on their safety, the EU Commission has also banned certain parabens, such as isopropyl- and isobutyl parabens. Despite this, clean beauty renounces any product that isn’t completely paraben-free. Amidst a cloud of misinformation, the controversy surrounding parabens stems from concerns over its role as an endocrine disruptor and speculated links to cancer.
A study performed in 1998 found that parabens are weakly oestrogenic (Routledge et al., 1998). An in vitro yeast-based oestrogen assay showed that this was true for the four most commonly used parabens. It also found that the oestrogenic activity of parabens increases concurrently with alkyl chain size. Butylparaben was 10,000-fold weaker than 17 𝛽-estradiol (the main natural oestrogen), while methylparaben was 2,500,000 times weaker. Rat-based experiments showed that parabens could also compete with estradiol for binding to the rat oestrogen receptor in vivo. However, butylparaben was 100,000 times weaker than estradiol, and methylparaben was completely inactive.
Despite the weak oestrogenic effects of parabens, clean beauty evangelists have been quick to sound the alarm. The EWG has jumped the gun and has claimed that parabens disrupt reproductive system functioning and fertility (Stoiber, 2019). Yet whilst parabens do have that effect when orally ingested by rats, like in the studies EWG cite (Boberg et al., 2016), the EWG doesn’t acknowledge that that’s not applicable to products that contain less than 0.8% parabens and are applied onto human skin.
The role of parabens as weak endocrine disruptors still left lingering fears with regards to excessive exposure to oestrogens and breast cancer. Cue the 2004 Darbre et. al study, which was arguably the catalyst for the sensationalised concern over parabens. The study found that parabens were present in 20 human breast cancer tumours, by extraction and analysis using thin layer chromatography (Darbre et al., 2004). This sounds worrying, but upon closer inspection, there are aspects of this study that render it an unreasonable way to pass judgement on the link between parabens and cancer.
The study found that parabens could possibly accumulate in human tissue due to long-term low-dose exposure through cosmetics, albeit at extremely low concentrations – the total mean paraben level in the tissues being 20.6 ng/g . However, the study itself is flawed, and it is unfortunate that clean beauty advertising has held onto it as proof against parabens. The most glaring issue is that there was no control group- parabens weren’t tested for in healthy tissue. There is nothing with which the paraben levels in breast tumours can be compared to. While the study recognises this, influential advocates of the clean beauty movement have completely overlooked this. Furthermore, parabens were also found in blank samples containing no tissue. Darbre et. al (2004) speculated that this was because of how widespread parabens are, which is reasonable. However, in some patients, the paraben levels were actually higher in the blanks. This could suggest that none of the parabens measured actually came from the breast tumours (Golden and Gandy, 2004).
All in all, the study is no grounds for a link between breast cancer and parabens. It seems unlikely that very low concentrations of very weak endocrine disruptors could cause breast cancer. For context, ethinyl estradiol, the oestrogen found in oral contraceptive pills, is 2,000,000 times more potent than butylparaben. Even so, it’s only linked to a small increase in cancer risk.
However, some consumers want to play it safe anyway and avoid parabens. Avoiding preservatives altogether would allow bacteria and fungi growth in products unless they’re completely sealed and airtight. Unfortunately, products can still look and smell fine despite being contaminated. Applying these products on the skin can cause infections, which is especially harmful in the eye area (Wilson and Ahearn, 1977). The bottom line is that almost any beauty product without preservatives compromises both its integrity and the safety of the user.
There is also the need to consider alternative preservatives, in the hopes that they can offer clean beauty some respite. “Natural” preservatives mostly consist of essential oils and organic acids. There are a wide variety of essential oils, and some of them have antibacterial properties. The downside is that many of them contain fragrant ingredients such as limonene and citronellol, which can be irritating (Scheinman, 1996). While essential oils are usually diluted to less than 1%, this can still trigger allergic reactions in sensitive skin types. It’s hard to just skim through an ingredient list and come to a conclusion, especially when formulations tend to include a blend of several essential oils. Parabens, however, are the least irritating and allergenic preservatives available, with an allergy incidence of 0.5-1.7% in the US and Europe (DeKoven et al., 2017). It is a little ironic that parabens are villainised by clean beauty, while essential oils are praised.
The takeaway: clean beauty advertising is misleading and promotes ingredients that are potentially irritating simply because they are “natural”. While some products are formulated as “clean” in order to be more inclusive, the clean beauty narrative itself is very deceptive. Further research still needs to be done on parabens, but as of now, there’s no direct link between parabens and cancer. Compared to its alternatives, parabens are more well-researched and have been used for much longer. If parabens still worry you, try using guidelines from the EU Commission. Methyl- and ethylparabens are of little concern, while propyl- and butylparabens are more potent.
References:
Boberg, J., Axelstad, M., Svingen, T., Mandrup, K., Christiansen, S., Vinggaard, A. and Hass, U., 2016. Multiple Endocrine Disrupting Effects in Rats Perinatally Exposed to Butylparaben. Toxicological Sciences, 152(1), pp.244-256.
DeKoven, J., Warshaw, E., Belsito, D., Sasseville, D., Maibach, H., Taylor, J., Marks, J., Fowler, J., Mathias, C., DeLeo, V., Pratt, M., Zirwas, M. and Zug, K., 2017. North American Contact Dermatitis Group Patch Test Results 2013–2014. Dermatitis, 28(1), pp.33-46.
Golden, R. and Gandy, J., 2004. Letters to the editor. Journal of Applied Toxicology, 24(4), pp.297-298.
Routledge, E., Parker, J., Odum, J., Ashby, J. and Sumpter, J., 1998. Some Alkyl Hydroxy Benzoate Preservatives (Parabens) Are oestrogenic. Toxicology and Applied Pharmacology, 153(1), pp.12-19.
Seo, J., Kim, S. and Kim, B., 2016. In vitro skin absorption tests of three types of parabens using a Franz diffusion cell. Journal of Exposure Science & Environmental Epidemiology, 27(3), pp.320-325.
Stoiber, T., 2019. What Are Parabens, And Why Don’T They Belong In Cosmetics?. [online] EWG. Available at: <https://www.ewg.org/californiacosmetics/parabens> [Accessed 1 September 2020].
Imperial Bioscience Review 