THE PLASTICS PROBLEM
As plastic pollution covers the globe, can science provide solutions? MICHAEL LUCY investigates.
NURDLES, AS THEY are disarmingly called, are pellets of plastic resin, the raw material shipped to manufacturers making plastic goods, and I am searching for them on a foggy midwinter morning at Shelly Beach in southeastern Australia, a seemingly pristine cove where endangered hooded plover nest among the rocks and waves roll in off water that stretches a clear 3,000 km to Antarctica.
My nurdle-hunting teacher and guide, Colleen Hughson, holds up several examples for inspection. Hughson is a filmmaker and producer who lives nearby in the town of Warrnambool. She has become something of an expert since nurdles began washing up on Shelly Beach in the hundreds of thousands in November 2017.
It takes a minute or two sifting through the sand and several false starts before I find my own: first a smooth speck of pumice, then two shell fragments, and finally a nurdle. Once I have my eye in I spot nurdles everywhere, tiny monuments to human endeavour that might live on here for centuries.
When Hughson first saw the nurdles, she says the whole beach “was just covered”. She had started a Facebook group of volunteers to tidy up litter on beaches around Warrnambool, inspired by the efforts of environmentally minded surfers who set out to protect the world-famous Bells Beach 180 km to the east. One Sunday she got a call from a member of the group who told her Shelly Beach was awash in plastic beads. “So I went down there the next morning to have a look.”
Over the next few days the lightweight, highly buoyant nurdles washed up along a 30 km stretch of coast. Hughson contacted the Victorian Environmental Protection Authority, as well as Wannon Water, the local water authority in charge of a sewer that discharges into the sea near Shelly Beach. The event was declared a state emergency.
The sewer outlet was quickly confirmed as the source. An unknown quantity of pellets – perhaps more than 4 million – had been dumped by a truck emptying a septic tank into a “sludge acceptance point” near Warrnambool Golf Course. The water treatment system was designed to catch objects sized down to 6 mm. About 3 million nurdles were caught inside the plant, but many slipped through, going down the drain and out to the sea.
No one knows how the nurdles got into the septic tank in the first place, or if they do they’re not talking. Wannon Water’s investigation narrowed it down to 20 suspects, but went no further.
As difficult as nurdles are to clean up, an estimated 570,000 were recovered from the coast over several months. An unknown number remain at large. Storms regularly churn up more from deep in the sand.
Now, more than six months later, after sifting through the sand for about 15 minutes we – mostly Hughson, whose sense for nurdles is unerring – collect a handful of nurdles and some other plastic debris.
The pollution feels particularly stark against the apparent isolation and purity of Shelly Beach, which Hughson describes as “the beach you come to if you don’t want to see anyone”. In Warrnambool, a town of 35,000, that’s saying something. But no place is isolated enough to avoid plastic now. Mount Everest is littered with water bottles; the Mariana Trench, the deepest spot in the oceans, is strewn with plastic bags. Microplastic fragments dot the Arctic ice and remote South Pacific island beaches are covered by a tide of trash. The problem is everywhere.
More than 8 billion tonnes of plastics have been produced since the 1950s, and most of that has been thrown away. By 2050, on current trends, plastic manufacturing will account for 20% of global oil use and 15% of carbon emissions. But arguably the most devastating environmental impact is caused by the amount of plastic waste washed into waterways and ultimately out to sea. More than 8 million tonnes ends up in the oceans each year, and that number too is growing exponentially. By mid-century it is estimated the amount of plastic in the world’s oceans will outweigh all the fish.
The millions of bottles and other plastic items that wash up on remote beaches are just the most visible tip of the plastic berg. Bags, straws and wrapping strangle fish, turtles and birds. Of greater concern is what happens to plastic exposed to the elements. Plastic is not biodegradable but it is photodegradable: sunlight breaks it down into progressively smaller pieces. These fragments turn the ocean into a plastic-- laced soup, its morsels slowly sinking to the bottom or eaten by fish. Mistaken for plankton, they are devoured by everything from krill to whales. This poses health dangers not only to those animals but to the entire food web, including humans.
The plastics themselves can contain toxins – often additives such as phthalates and bisphenol-a, which are used to change the properties of the plastic, but may be “endocrine disruptors”, which have undesirable hormonal effects on animals. Floating plastic particles can also behave like sponges, soaking up pollutants in seawater and delivering a concentrated dose to whatever is unlucky enough to eat them.
Human intake of microplastics is already widespread. The health impacts are still unknown but in 2017 a British Medical Journal editorial declared it “time to pull our heads from the sand” regarding the risks.
The nurdle I held in my hand at Shelly Beach, gave me a small grip on a problem of unfathomable dimensions. Thought it weighs a fraction of a gram and is worth around a thousandth of a cent, it will no doubt outlive me.
It sits on my desk as I wonder: can science, which created plastic, also provide solutions?
FROM THE CARBONIFEROUS TO THE ANTHROPOCENE
The nurdles at Shelly Beach are tiny lumps of polypropylene, the second most common kind of plastic, after polyethylene.
Like most plastics they are made from petroleum
byproducts, which means their story likely began hundreds of millions of years ago, when algae or zooplankton died and settled to the bottom of the ancient ocean. As sediment collected above, the heat and pressure grew and the sludgy mixture formed a solid substance called kerogen, made up of both organic and mineral material. Millions of years passed and the kerogen sank deeper into the Earth’s crust, where more heat and pressure slowly transformed it into the hydrocarbon slurry we know as petroleum. There it sat as the ages went by, until humans appeared on the surface above and developed the tools to tap its chemical properties.
In the 19th century, the aftermath of the industrial revolution saw a demand for new materials – at first as substitutes for rare or expensive materials like ivory – and the scientific and manufacturing knowhow to make them mass commodities. The first widely available plastic, celluloid, was plant-derived, made from a nitrocellulose and camphor resin. Patented in 1869 by an American inventor named John Wesley Hyatt, celluloid was designed to win a prize offered by a billiard-table manufacturer seeking a synthetic replacement for ivory billiard balls. Celluloid did the trick, though it was not without its drawbacks: as Hyatt recalled in 1914, “occasionally the violent contact of the balls would produce a mild explosion like a percussion guncap”. (Nitrocellulose is highly explosive.)
Nonetheless the age of plastic had begun. As oil extraction grew in the second half of the century (in 1859 US oil production was 2,000 barrels, by 1899 it was 57 million), to provide fuel oil and kerosene, chemists turned to petroleum as a source of the raw molecules that bind together into the long chains of carbon and hydrogen which give plastics their characteristic combinations of malleability and toughness.
By the 1940s, plastics were becoming part of everyday life. They were in the celluloid film that made motion pictures possible, in the ubiquitous Art Deco Bakelite jewellery, in the cheap toothbrushes in any corner shop. According to a 1941 article in Harper’s Magazine, they were “wonder materials” made from “such simple ingredients as air, coal and water”.
It was World War II that really helped plastics come into their own. As metals and other materials were requisitioned for military use, manufacturers sought alternatives. Nylon, for instance, became popular for stockings because all the silk was going to make parachutes. The military also embraced plastics for their desirable properties of strength, heat resistance, electrical insulation and flexibility.
By 1955 disposable and single-use plastics were celebrated. A LIFE magazine article titled ‘Throwaway Living’ showed a family joyfully tossing away food containers, vases, curtains, nappies, and dozens of other items in a modern triumph over the drudgery of cleaning and reuse.
Worldwide production of plastics quadrupled from 2 million to 8 million tonnes a year in the 1950s. By 1970, it was 35 million tonnes. In 2017, it was 400 million tonnes. Production is estimated to continue doubling every dozen years. Of the 8 billion tonnes of plastic produced in the past seven decades, more than half has been produced in the past two. Of that, 30% is still in use, about 10% has been incinerated and almost 60% has ended up in landfill or as litter. And because humans tend to live near waterways, a significant percentage of that plastic litter gets washed into rivers and the ocean – some 80% of ocean plastic arrives this way. The rest is what’s tossed out of boats.
With discarded plastic now forming a thickening skin over the planet, the presence of plastics has been proposed as one of the key markers of the Anthropocene, the present epoch in which the planet has been unmistakably transformed by human activity. Indeed, archaeologists are already using strata of different kinds of plastic polymers to establish eras.
How long plastic particles will stay in the environment is unknown, says oceanographer Juliana Assunção Ivar do Sul of the Leibniz Institute for Baltic Sea Research in Germany. She is the plastics expert in the Anthropocene Working Group of the International Commission on Stratigraphy, which sets the official names and boundaries of periods in the deep history of Earth.
“Once plastic is deposited in sediment we know it degrades very slowly,” she says.
WHAT CAN BE DONE?
Just as there is no single “cure for cancer”, there is unlikely to be a single cure for plastic pollution. Plastics comprise hundreds of materials used for thousands
Worldwide production of plastics was 2 million tonnes in 1950. In 2017, it was 400 million tonnes.