Micro and nanoplastics are increasingly familiar words, as people become aware of the environmental impact of decades of over-use and poor disposal of the plastics endemic to modern society. Thrown ‘away’ is still somewhere, as we are increasingly learning, and the plastics that slip through our fingers don’t disappear but too often find their way into ecosystems far from ourselves. Not just from the plastic bags that we are learning not to use, or the bottles, crisp packets and babies’ nappies that we see littering the beach, but also the plastics that we don’t see, that dominate production, transport and operation in all aspects of modern life. The usefulness of this miracle material that entered our lives in the early 20th century is reminding us of its indestructible nature as we reap the consequences of its use in the 21st century.
Once released into the environment and exposed to factors such as UV-light and mechanical forces (such as water), large plastic structures break down into smaller sizes that can be dispersed widely both on land and in water. These tiny plastic particles are increasingly demonstrated to be accumulated within ecosystems and, as technology becomes available to measure on a smaller and smaller scale, we start to see these particles in water, soil and organisms down to a single cell. Out of sight is definitely not out of mind – just ask a plankton.
The dawn of microplastics and a step into the nano-unknown
‘Microplastic’ is the term officially used to describe plastic fragments smaller than 5 mm (0.5cm), and this includes particles right down into the nanoscale, so smaller than 100nms (0.000001cm). Although science is increasingly good at the precise measurement of the nanoparticles that we manufacture, collection and identification of nanoscale plastic particles from the wild is much harder, and methods are only just starting to be validated. Difficulties include the huge variety of particles that are captured, with naturally occurring materials, such as clays and organic matter, the hugely dominant fraction of any sample. It’s a nano needle in a haystack when nature also works at the nanoscale and a long way from measuring a pristine example of a known nanomaterial in a jar.
What’s in a name?
When it comes to nanomaterials, plenty. Governments around the world have precisely defined regulatory frameworks that companies use to gain approval for market access. The REACH framework in the EU is probably the daddy of them all, with the EU’s precautionary principle (‘prove that it’s safe’, rather than the ‘prove that it’s not’ position of the US), setting the standard for the approvals needed for chemicals, including those at the nanoscale.
However, before you start your regulatory journey, you need to define what a nanomaterial actually is, not just the size of a particle but also where it comes from. Here you enter the world of engineered (manufactured) nanomaterials compared to naturally originating (incidental) nanomaterials.
The natural world is literally full of materials at the nanoscale – nature is the ultimate chemist. From your glass of milk to the colours in a butterfly’s wing, you are looking at complex natural nanomaterials and structures.
Incidental nanomaterials do not bring quite such lovely visions, these are produced as a by-product of a process and we need look no further than car exhaust fumes as an example, or a candle burning on the windowsill. Our own lifestyle produces more incidental nanomaterials than we will ever manufacture.
Neither naturally occurring nor incidental nanomaterials are covered by regulatory frameworks such as REACH. It is intended for engineered or manufactured nanomaterials, where a company registers a substance (e.g. titanium dioxide) that it intends to manufacture for specific uses, with detailed information on its properties and safety. These nanomaterials carry with them extensive characterisation and safety testing so that regulators can be sure that they are safe for products and processes in approved types of applications (e.g. bound into a matrix, rather than released as an aerosol).
In the commercial nanomaterials sector, there is no such thing as a ‘nanomaterial’ on its own – it’s engineered or incidental or naturally occurring, and nanomaterial-producing companies, from tiny start-ups to multi-nationals, use their language with precision to ensure that products are fully identified at all times and by all people. An Engineered Nanomaterial is exactly that – enabling the ‘smaller, harder, further and faster’ that we see in products all around us.
Nanoplastics – an identity unmasked
The ‘Nanoplastics’ in our newspapers have a more complex identity than their name suggests. These nanomaterials have never seen the inside of a nanomaterials company and started their life as part of a much larger material – they are incidental nanomaterials and should always be defined as such.
The nanomaterials industry in Europe works to ensure that safe engineered nanomaterials are used in products world-wide. Use of the term ‘nanoplastics’, without describing their origins, risks the perception that the plastic particles now being found throughout our ecosystems were intentionally produced. Infact the opposite is true, there are almost no engineered nanoplastics in production or use, with scientific research using tiny quantities of material as one of the primary applications.
From zero to hero
The engineered nanomaterials sector (researchers and companies) can in fact, play a very positive role in helping to identify and understand the incidental nanoplastics that are increasingly visible to us in our landscape. Rapid advances in characterising and understanding engineered nanomaterials, will help scientists worldwide to find, identify and understand the biological interactions of incidental nanoplastics and address their impact on the environment. This can enable all measures necessary to reduce their occurrence, reaching back up through the long industrial and societal pathway through which they were produced.
Dr Claire Skentelbery
Following a degree in agriculture and PhD in biochemistry, Claire worked within scientific marketing and cluster development, working within the Cambridge (UK) biotechnology cluster. She has spent the majority of her career within scientific networks and associations, having been a founder (and manager) of the Council of European BioRegions and also Secretary General of the European Biotechnology Network.
She has been the Director General of the Nanotechnology Industry Association since 2017 and focuses on the market access barriers for nanomaterials, including regulations, with a particular interest on overall economic development of the nanomaterials industry and its evolution policy-wise at a global level.
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