Trashed to the end of the world: The pollution caused by plastic waste is increasing at an alarming rate, as the most extensive study to date on the global problem illustrates. The oceans are particularly threatened, the researchers warn: if it continues, the entries will almost triple by 2040. However, the scientists also give room for hope: Measures on a global level can at least drastically contain the pollution, according to the model analyzes.
Everyone has already seen the problem with their own eyes, because the ugly signature of human civilization is visible in many places: rubbish lies around or bobs on the banks of the water. The plastic materials from packaging, bags and the like are particularly problematic because they only disintegrate but no longer disappear from nature. In addition to the larger pieces, it is teeming with so-called microplastics in soils and especially in the seas. These particles damage the ecosystems and ultimately humans, according to studies. So far, the entire extent of the threat from plastic pollution can only be guessed at, experts say.
But what factors play a role in the global spread of plastic waste in the environment, what will the future development look like and where could the lever be applied? An international team of 17 experts has now looked into these questions. You have collected and evaluated specific information about the entries, the causes and processes. Using the data, they developed a computer model to track the stocks and flows of plastic waste around the world and to estimate future developments.
It is getting worse!
Their calculations show that if no measures are taken, a total of 1.3 billion tons of plastic will end up in the terrestrial and marine environment between 2016 and 2040. For the sensitive ecosystems of the oceans, the pressures are particularly critical. If the current trend continues, the amount of plastic that enters the oceans each year will increase from 11 million tons to 29 million tons over the next 20 years.
Since plastic is hardly biodegraded, the amount in the oceans could increase by a total of 600 million tons by 2040 – this corresponds to the weight of more than three million blue whales. “For the first time, the study provides a comprehensive insight into the dizzying amounts of plastic waste that end up in the world’s terrestrial and aquatic ecosystems. We now also have a much clearer picture of the sources of pollution, ”said co-author Costas Velis of the University of Leeds.
As the researchers report, the basic problem is that around 95 percent of plastic packaging is used only once before it becomes waste. The researchers identified the lack of disposal of municipal waste in the poorer regions of the world as the most important cause of the spread of waste in the environment. According to this, around a quarter of all plastic waste is currently not collected, leaving it up to the individual to get rid of it himself – with fatal consequences. The “wild” landfilled waste then spreads into the environment and then ends up in the sea. Without countermeasures, this problem will worsen significantly due to demographic developments around the world, warn the researchers: by 2040, a third of all plastic waste generated could not be collected.
Main problem: lack of disposal
“The scale would be even larger if a huge amount of waste were not openly incinerated in some regions – but this incineration also causes significant environmental problems,” says Velis. His colleague Ed Cook explains: “Modern incinerators with air pollution control technology emit very few dangerous substances. But open combustion creates many types of harmful substances. This open burning process reduces the amount of plastic, but it also poses many other problems and also makes a significant contribution to global warming, ”says the researcher.
As the researchers’ modeling shows, immediate and concerted efforts can greatly reduce the environmental impact of plastic. According to this, measures that could actually be implemented would reduce the total amount from 1.3 billion tons in the period from 2016 to 2040 to 710 million tons of plastic waste. However, this would still correspond to pollution of the terrestrial environment with 460 million tons and water pollution of 250 million tons.
Countermeasures are possible!
In high-income countries, the focus should be on reducing plastic consumption and improving product design and recycling, the scientists say. In addition, there should be no more waste exports. However, the most influential single factor in reducing global pollution would be the improvement of waste collection services in poorer countries. “Our modeling shows that each additional ton of plastic collected reduces pollution of the aquatic environment by 0.18 tons,” says Velis. “The focus of the solution approaches should therefore be the provision of services and infrastructures for disposal”.
According to the researchers, it also makes sense to promote the previous informal waste collection system: many people around the world live by searching waste that has not been collected for material that they can resell for recycling. It is estimated that they collect about 58 percent of the total plastic material that is recycled worldwide. “Without the garbage collectors in the global south, the mass of plastics that get into the environment would be considerably larger,” says Velis. The involvement and promotion of waste collectors is therefore crucial for supporting the circular economy in the global south.
The scientists emphasize that there are no simple solutions that could reduce the flow of plastic waste into the environment, and especially into the oceans. However, as part of their study, they show the possible approaches that, taken together, could reduce plastic flow into the ocean by 80 percent of the level forecast for 2040. “The corresponding interventions can all be carried out with existing and already mature technologies,” says Cook. He and his colleagues now hope that humanity will actually be able to counter the global garbage problem.
Source: University of Leeds, Pew Charitable Trusts, professional article: Science, doi: 10.1126 / science.aba9475