Microplastics : A thread for male fertility

What are microplastics?

Plastic is a petrochemical (i.e. oil-based) polymer used as a basic material in almost every industry, including cosmetics, in the form of a dissolved (liquid) polymer as a texturizing, thickening or stabilizing agent. The concern however, is that plastics spontaneously fragment over time into smaller particles, ultimately becoming what are known as "microplastics" (≤ 5 mm) or "nanoplastics" (≤ 1µm). 

Photo : Oregon State University

How microplastics affect the human body ?

These micro- and nanoplastics can penetrate biological membranes and enter our bodies. Some plastics or plasticizers have already been shown to have harmful effects on human health, such as bisphenol A, classified by the Swiss Federal Office of Public Health as "endocrine disruptor" and banned from use in baby bottles throughout Europe in 2011.

Scientists now believe that microplastics may act on male fertility, namely as a testosterone suppressor. Phthalates, for example, have been the subject of numerous studies demonstrating their association with genital anomalies, such as reduced penis size, incomplete testicular descent, and erectile dysfunction^1-4. Although a number of phthalates have been banned by the European Union, others are listed in the REACh  regulation as substances of concern but are still authorized in Switzerland (for instance in cosmetics) provided they do not exceed a content of 0.1% of the object's total weight. 

Also alarming, a meta-analysis including data on 42,935 men worldwide showed that sperm quality declined by 50-60% between 1973 and 2011⁵. Although the association with the global presence of microplastics cannot be proven, the authors strongly suspect that plastic pollution is one of the causes.

Microplastics in the environment

Plastic does not biodegrade. Once the polymer has reached a sufficiently small size, it can easily travel through water and air, loading itself with pollutants. Unfortunately, plastics often end up in the oceans, where they are absorbed by marine fauna, posing a major threat to species and entering the food chain.

Zero plastic in Beyond Men's Care products

Despite these worrying data, almost 80% of cosmetics contain some form of plastic. Yet there are natural alternatives to replace plastics in cosmetics. It is possible to use natural gums instead of plastic thickeners, or emulsifiers based on renewable raw materials. That's why at Beyond Men's Care, our formulations do not contain any type of plastic, whether phthalates, dissolved polymers, colloidal polymers or crosspolymers.

How to identify polymers and microplastics in products ?

On the product's INCI list, look for endings like -one, -oxane, -siloxane, -polymer, -vinyl, -cellulose, which are plastics. They may also contain -co-, -polymer-, -acrylate-, -polyquat-, -carbomer-. Finally, you may recognize polyethylene glycol (PPG) and polypropylene glycol (PPG) polymers.

References

1. Thompson RC, Moore CJ, vom Saal FS, Swan SH. Plastics, the environment and human health: current consensus and future trends. Philos Trans R Soc Lond B Biol Sci. 27 juill 2009;364(1526):2153‑66. 

2. Swan SH, Main KM, Liu F, Stewart SL, Kruse RL, Calafat AM, et al. Decrease in Anogenital Distance among Male Infants with Prenatal Phthalate Exposure. Environ Health Perspect. août 2005;113(8):1056‑61. 

3. Swan SH. Environmental phthalate exposure in relation to reproductive outcomes and other health endpoints in humans. Environ Res. oct 2008;108(2):177‑84. 

4. Kortenkamp A, Scholze M, Ermler S, Priskorn L, Jørgensen N, Andersson AM, et al. Combined exposures to bisphenols, polychlorinated dioxins, paracetamol, and phthalates as drivers of deteriorating semen quality. Environment International. 1 juill 2022;165:107322. 

5. Levine H, Jørgensen N, Martino-Andrade A, Mendiola J, Weksler-Derri D, Mindlis I, et al. Temporal trends in sperm count: a systematic review and meta-regression analysis. Hum Reprod Update. nov 2017;23(6):646‑59. 

By Valentine Du bois

Master's degree in medical biology, University of Lausanne, Switzerland

Valentine holds a Master's degree in medical biology from the University of Lausanne, following a Bachelor's degree from the University of Geneva. During her Masters, Valentine specialised in the fields of pharmacology and toxicology, focusing on applied laboratory research for the development of new treatments.