By Dave West
Microbeads are tiny plastic microspheres added to a range of products as a gentle abrasive in personal care (exfoliants, body washes toothpaste, etc.) and household cleaning (detergents, waxes, and polishes) and are also used in health science research, microscopy techniques, fluid visualization and fluid flow analysis, and process troubleshooting.
Microbeads at 50 times zoom
Generally made from polyethylene (but can be also be made of polypropylene (PP), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) and nylon), microbeads are commercially available in particle sizes from 10 µm to 1000 µm (1mm) in diameter. To give perspective on how small these microbeads are - a human hair is around 18 µm in diameter.
Although useful in some of their medical applications, microbeads pose an environmental hazard when disposed of in waste water, as they are so small pass through filtration systems in sewage treatment plants without being captured.
Their use and disposal creates plastic particle pollution of our waterways, coastline and oceans. Like all plastics, micro and nano scale plastics like microbeads have significant potential to act as a toxic sponge – sucking up persistent organic pollutants and heavy metals to become a major vector for distributing toxic materials across the environment and importantly into our food chain. Micro and nanoplastics are seen to be a more direct threat than plastics generally as they are readily mistaken for fish eggs, zooplankton and other sources of marine food. There are serious concerns that when seafood ingests microbeads it creates significant potential to pass through the food chain and onto our dinner plates.
Reports have shown that even if using sophisticated (and expensive) processes for settling solids in sewage to remove up to 99% of microbeads from the final effluent that is pumped into our waterways, these processes would still create a major source of pollution. For example, it has been estimated if just 1% of microbeads escape capture in the sewerage treatment plants across the San Francisco Bay area, some 471 million microbeads would be released every single day. Screening systems in Australian sewer capture very few if any microbeads.
While the extent of the problem in Australia remains unknown, a single tube of deep facial cleanser can contain 350,000 microbeads, demonstrating that the level of microbead pollution is substantial. Based on international estimates it is likely around 650 tonnes of microbeads enter Australia’s marine ecosystems annually.
Microbeads can play a constructive and vital aspect of some products, but justification for the use in consumer goods is very problematic.
As a result of high profile campaigns in Australia and across the globe many manufacturers and retailers have begun to phase out their use. Last year, the Microbead-Free Waters Act of 2015 was passed in the U.S.A. prohibiting the manufacture and introduction into interstate commerce of rinse-off cosmetics containing intentionally-added plastic microbeads, by July 1, 2017.
There is strong momentum for a ban in Australia, Federal Environment Minister Greg Hunt announced in December 2015 that state and territory governments had agreed to a voluntary phase-out of microbeads in cosmetics by July 1, 2018. In January of this year Coles and Woolworth’s both announced that they would stop using microbeads in their own products from 2017, while global companies including Unilever, Beiersdorf, Johnson & Johnson and The Body Shop have already commenced the phase-out.
While we congratulate the Federal Government on their commitment to a phase out, the timetable of July 2018 is too slow. There may also be problems with ‘free riders’ under a voluntary agreement and legal action will likely be necessary to capture all producers.
Boomerang Alliance is calling for the ban on microbeads to include laundry detergents and cleaning products as well as cosmetics and personal care products by July 2017, and must be underpinned by legislation to ensure any substitutes are safe to enter the environment.