Rarely has a global environmental issue aroused public and political concern more rapidly than plastic pollution of the oceans. Images of litter-coated beaches on once idyllic islands — and sea creatures entangled in lethal debris or poisoned by plastic pieces mistaken for morsels of food — are forcing governments and companies into overdue action to reduce the estimated 8m tonnes of waste plastic that find their way into the oceans every year. So too is alarm about the almost invisible threat of tiny microplastic particles and fibres, resulting mainly from the disintegration of larger items, which may pose a toxic time bomb for marine life and eventually humans too.
This initial drive for action must not only be maintained but intensified in the years ahead. The threat to our oceans is too great to release the political pressure even if plastic pollution falls out of the news.
Unfortunately it will not be practical for the foreseeable future to remove more than a small fraction of the trillions of plastic pieces in all shapes and sizes that are already fouling the oceans. Yes, beaches and estuaries should be cleaned — and it is worth supporting projects to extract plastic from places where currents concentrate floating debris such as the notorious Great Pacific Garbage Patch — but purifying the oceans on a global scale is an unrealistic technical challenge.
Policymakers should therefore focus their efforts on rapidly reducing the flow of fresh material into the ocean, by increasing recycling and restricting non-essential uses of plastics. This will require a huge change in behaviour by the world’s consumers, pushed by government regulations such as mandatory deposits on plastic bottles, charges for plastic bags and coffee cups, and bans on certain products, such as the one proposed last week by Theresa May, UK prime minister, on plastic straws and cotton buds. At the same time the manufacturing and retail sectors must go further and faster than most have announced so far to phase out unnecessary plastic packaging.
Even so, millions of tonnes of plastic will still need recycling every year for the time being. Product designers have an important role to play in the creation of a “circular economy”, making it simpler to separate different components at the end of their life and identify different plastic ingredients.
A priority for research is to improve recycling technology. A hint of what might be possible came last week when an international team announced the discovery of an enzyme that can break down PET, the polymer used to make bottles; it was extracted from bacteria evolving to eat waste plastic in Japan. The next big EU research programme could lead the way by adopting plastic-free oceans as a “grand challenge”.
All these actions must take place on a global scale, since most plastic reaches the sea from the developing world and particularly from the larger Asian economies. That may mean transferring money and even technology to help poorer countries handle the huge recycling job that they face.
Fortunately plastic pollution, unlike climate change, is an environmental cause without a vociferous band of sceptics denying the scientific consensus that action is needed urgently. In that respect it is more like the 1980s crisis over the destruction of the protective ozone layer in the upper atmosphere. Then international agreement quickly banned the non-essential use of ozone-destroying CFC chemicals in aerosols, fridges and elsewhere. The battle against unnecessary plastics will not be so straightforward but we can draw some encouragement from successful phase-out of CFCs 30 years ago.
Letter in response to this article:
Get alerts on Waste management & recycling when a new story is published