Microplastic (polyethylene) particles extracted from Garnier PureActive anti-blackhead deep pore wash.
Microplastic particles extracted from Johnson & Johnson Blackhead clearing daily scrub (left) and Tesco cucumber face scrub (right).
Microplastics are currently defined as "plastic particles smaller than 5mm in their longest dimension" (1) but those used in cosmetics preparations are considerably smaller than this and in the photomicrographs above are at least tenfold smaller. This definition is likely to be modified in the future as 5mm is hardly 'micro' but was chosen as an upper limit to include small but easily visible fragments found in the environment, in particular on beaches and in beach sand. No lower limited has yet been set.
It is an immutable fact that no matter where one is standing on the Earth water always flows downhill. This ultimately means that just about all the water flowing in the world's rivers ends up in the world's seas and oceans and by extension, most of what is in the water whether dissolved or suspended also ends up in the oceans. We are all aware of the pollution problems caused by plastic bags, bottles and other plastic packaging but how many of us over the past few decades have considered that by merely going through our morning ritual of washing with exfoliating preparations and brushing our teeth we may have become unwitting contributors to global marine plastic pollution?
Thanks to the cosmetics and personal care industry that is exactly what has happened(2). Not necessarily out of malevolence but simply through ignorance, ill thought out or thoughtless product design and the desire for greater profits.
Many cosmetic and personal care products include in their list of ingredients polyethylene which is in the form of micro plastic particulates and is incorporated into body scrubs, facial cleansers and some toothpastes as a mild abrasive. The particles are not biodegradable, are easily flushed into the waste water system but due to their extremely small size are not trapped and removed by the standard filtration systems at waste water treatment plants(3). As a consequence thousands of tonnes of micro- or nanoplastic particles, directly from personal care products, find their way into the seas and oceans annually adding to the hundreds of millions of tonnes of microplastics already in existence.
A major disadvantage with plastic is it's not biodegradable and is also very resistant to degradability under natural conditions. Just about all we produce ends up as waste that has to be dealt with. In 2013, 300 million tonnes of plastic was manufactured globally, 57 of which were manufactured in the EU. "Studies showed that 40% of plastic waste goes to landfills, 14% is recycled but 32% ends in the marine environment as litter. The Earth‘s oceans were found by selective surveys of waste to contain millions of tonnes of plastic pieces, mostly in the form of microplastics".(4)
Polyethylene ((IUPAC name: polyethene or poly(methylene))) has a specific gravity of between 0.91 to 0.96 meaning it floats in water. In the marine environment the result of this is that it circulates in the water column with zoo plankton. It is a hydrophobic material and behaving like a sponge it "is liable to concentrate hydrophobic persistant organic pollutants (POPs), which have a greater affinity for the hydrophobic surface of plastic compared to seawater".(5) POPs are known to bioaccumulate through the food web. The smaller the microplastic particle the greater the surface area-to-volume ratio and the greater the contamination with POPs. At sub millimetre sizes, micro-particles are being ingested by the co-existing zooplankton which in turn are being preyed upon by larger organisms. Plastic particles with a toxic payload are entering the food chain and the higher up the chain an organism is the greater the concentration.
|Scanning electron micrographs of microplastic particles isolated from exfoliating personal care products.
|Boots Skin Clear daily face scrub
||Tesco cucumber face scrub
|Garnier PureActive anti-blackhead deep pore wash
||Johnson&Johnson Clean & Clear blackhead clearing daily scrub
If you want to be thoroughly depressed by marine plastic pollution in general have a look at the 3-part YouTube video "Garbage Island: An Ocean Full of Plastic"
1. Proceedings of the International Research Workshop on the Occurrence, Effects, and Fate of Microplastic Marine Debris.
NOAA Marine Debris Program, National Oceanic and Atmospheric Administration, U.S. Department of Commerce, Technical Memorandum NOS-OR&R-30
2. Contributing to marine pollution by washing your face: Microplastics in facial cleansers.
Lisa S. Fendall, Mary A. Sewell. Marine Pollution Bulletin 58 (2009) 1225–1228
3. Transport and fate of microplastic particles in wastewater treatment plants. Steve A. Carr, Jin Liu, Arnold G. Tesoro.
Water Research 91 (2016) 174-182
4. Global Plastic Waste and Oceans’ Pollution. Million tons of plastic waste have gone missing in the world oceans?
Athanasios Valavanidis. Department of Chemistry, University of Athens, University Campus Zografou, 15784 Athens, Greece.
Scientific Report, 26 May, 2016
5. The physical impacts of microplastics on marine organisms: A review
Stephanie L. Wright a, Richard C. Thompson, Tamara S. Galloway
Environmental Pollution 178 (2013) 483-492