Microplastics in Sunscreens

Microplastics are one of the most important health and environmental problems we face today (1). They are insidiously everywhere. Finding their way from products we consume, into our bodies and out again.  

Although almost invisible to the naked eye microplastics fill our solid waste on land, and are eventually washed into the sea. Almost all microplastic waste in our ocean originates on land (1) but finds its home in the plastic soup in our oceans. 

Microplastics have been linked with health risks in the respiratory, immune, reproductive, and digestive systems (2).  Two common microplastics that have been linked with genotoxicity, cytotoxicity, DNA damage, inflammation, and immunological responses in humans  are polystyrene and polyvinyl chloride (PVC)  (2).  Both of these chemicals are used in cosmetics to form a film on top of your skin, or to put it another way, to cover your skin in a layer of plastic.  

Microplastics are also intentionally added to sunscreen formulations for such reasons as waterproofing or to hold the product together (3). They can also be used as cheap alternatives to more expensive ingredients. This is the case of Sunspheres which are styrene/acrylate copolymers that do not absorb UV irradiation but instead enhance the effectiveness of the active organic UV filters (4). They are polymer beads which are filled with water that eventually leaves the particle, leaving behind tiny air filled spheres (4).  These spheres redirect the sunlight to the actual working UV filters, allowing less of the filter to be used. 

When buying a sunscreen it is important to check for plastic packaging, but also fundamental to check inside the product too. Let's reduce this plastic environmental disaster by choosing products that are completely plastic free. For more information check out the Beat the Microbead website and download their app to do a home investigation on all your personal care products. 

1. Golwala, Harmita, et al. "Solid waste: An overlooked source of microplastics to the environment." Science of the Total Environment 769 (2021): 144581.
2. Guerranti, C., et al. "Microplastics in cosmetics: Environmental issues and needs for global bans." Environmental toxicology and pharmacology 68 (2019): 75-79.
3. https://www.beatthemicrobead.org/72-of-sun-care-products-contain-microplastics/
4. Kaimal, Sowmya, and Anil Abraham. "Sunscreens." Indian Journal of Dermatology, Venereology and Leprology 77.2 (2011): 238.