Microplastics: can we clean up the oceans and seas using technology?

They might not be more than a millimetre in length, but they can cause irrevocable harm to our health and the planet. Microplastics are fragments of synthetic materials produced as a result of waste decomposition and industrial processes. This went unnoticed and uninterrupted for years at first, and consequently they are now all around us, particularly in the water of our seas and oceans.

Getting rid of microplastics altogether is a utopia, but several groups of scientists from all over the world are hard at work developing technology that may help us to identify them, analyse them and evaluate the risks on a case-by-case basis. Furthermore, some scientists are even trying to devise strategies for capturing microplastics or at least stop them spreading by coming up with new, biocompatible materials to substitute what we currently use.

But where do microplastics actually come from and how are these invisible enemies created? And what are the innovation solutions that could – one day – eliminate them from the face of the earth all together?

 

The heart of the problem

Microplastics – named as such on account of their size, unsurprisingly – come from many different sources. They might be released into the environment as ingredients in detergents and cosmetics, or as a result of manufacturing processes in sectors like clothing. They can also be generated as a result of the gradual fragmentation and disintegration of objects like containers, bags, construction materials and tyres.

There are around 90,000 tonnes of plastic floating in the Pacific Ocean around the islands of Hawaii alone, a phenomenon that has been dubbed the Great Pacific Garbage Patch. This island of rubbish began forming in the 1980s as a result of ocean currents, which swept in garbage from all over the world. To make matters worse, there is a similar phenomenon forming in the Atlantic, leaving no doubt that the proliferation of microplastics is out of control and will prove nigh-on impossible to stop.

 

Think big

One of the largest initiatives pushing to solve the problem is Ocean Cleanup. Currently in the trial phase, the project is aiming to get rid of the Great Pacific Garbage Patch we spoke about earlier. How? By using a gigantic, floating trap which uses the natural power of waves to attract rubbish, thus allowing boats to come and collect it. It’s a colossal task involving huge barriers on the surface of the water, yet despite the big promises (and high expectations) surrounding the plan, Ocean Cleanup has so far failed to achieve its objective. Not only are contraptions like the one being used in the Pacific unable to capture microplastics, which float beneath the surface, but right now it’s struggling to contain the larger, surface plastic too. Needless to say, there’s a lot of work to do.

 

Think small

Another approach is to work from the bottom up, by adopting a detailed, almost surgical strategy to clear up these materials. These initiatives use chemicals in all sorts of different ways to tackle the problem.

One strategy is to build filters capable of capturing large quantities of substances that have been let out into the water. These are micro- and nano-particles specially designed to identify and join up different types of harmful substances, grouping them together make them easier to collect and dispose of. These miniscule, smart sponges could be a useful tool for collecting metals, hydrocarbons, pesticides and – why not? – microplastics in some of the most difficult-to-reach places.

The idea of bioplastics is another strategy that’s worth pursuing alongside this. It would involve us ceasing to produce non-recyclable materials and instead producing objects using natural resources such as algae and by-products of the food and agriculture industry such as cereal husks and salad leaves. Scientists are no longer under any illusions: plastic should not just be recycled and disposed of safely, but completely rethought.