The question of microplastics and their impact on both the environment and human health is currently a hot topic of research and discussion. Unsurprisingly, cosmetics have also come under scrutiny.

Fact: The biggest sources of microplastics in the environment are fishing nets, washed clothing (due to synthetic fibers), and plastic bottles. Cosmetics rank somewhere around 10th place on this list.

In humans, microplastics mostly enter the body through wastewater, which carries particles from the sources mentioned above. Criticism aimed at cosmetics—and particularly sunscreens—in this context is often exaggerated and unfortunately increases public anxiety.

The highest concentration of microplastics in cosmetics is found in makeup products, where they are used to enhance sensory properties—such as texture and visual effects on the skin. Interestingly, the claim that "microplastics are cheap fillers" is inaccurate. In many cases, these ingredients are actually quite expensive.

There is a study (available under the original title: "Assessment of human dermal absorption of flame retardant additives in polyethylene and polypropylene microplastics using 3D human skin equivalent models") in which researchers used cultured skin cell models (recognized alternatives for dermatological studies). They applied various substances—specifically those related to textiles, not cosmetics—and tested what happens when fabric containing microplastics and flame retardants is worn on dry and moist skin for 24 hours.

What did they find? Systemic absorption (meaning absorption into the entire body) was minimal. The substances were generally not detected in the body, except under specific conditions. These included heavily moisturized skin under occlusion (like a film barrier) and impaired desquamation. In such cases, certain forms of microplastics could be absorbed. While this does not reflect typical real-life exposure, the findings still provide a foundation for improved legislation, which is a positive outcome. Unfortunately, the same study is already being used as a tool to spread fear and misinformation.

Another study by Korean researchers examined the impact of microplastics on the skin. They found that high doses of microplastics can trigger the production of inflammatory cytokines—but only if the particles penetrate deeply into live keratinocytes or fibroblasts, which is virtually impossible through normal external skin contact.

Can you identify microplastics through the INCI (International Nomenclature of Cosmetic Ingredients) list?
Some ingredients are always microplastics—for example, nylon, which is still found in some decorative cosmetics but will likely be banned in the future. Others, such as polypropylene (once used in scrubs), have already been banned and are no longer used.

However, copolymers are not always microplastics—it depends on their solubility and particle size ("building block size"). For example, polyquaterniums, which often appear in alarmist claims, are not considered microplastics.

Article author cosmetic chemist
Yuliia Gagarina