Plastic products are omnipresent in our lives. When they are no longer needed, we throw them away. But what happens to the plastics afterwards? For the first time, scientists have taken a global inventory of the plastic waste that accumulates in the environment. According to the results, some countries throw away significantly more plastic waste than others and do not dispose of it in an environmentally friendly manner. Among the less glorious hotspots, India, Nigeria and Indonesia are at the forefront. One reason: in poorer countries in particular, there is often no garbage collection service; instead, the waste is burned or thrown away. The survey is now intended to help politicians improve regional waste disposal and recycling. This would not only benefit nature, but also our health.
We use countless plastic products in our everyday lives. More than 400 million tons of plastic are produced every year. They were once invented to create lightweight yet durable materials for packaging and everyday objects. But plastic is usually so robust that it only breaks down extremely slowly in nature and therefore increasingly accumulates in the environment. This plastic pollution represents a global challenge because it has a negative impact on ecosystems and human health. But exactly how, in what form and in what quantities does the plastic end up in nature? And where is a particularly large amount of plastic thrown away?
Where and how much plastic ends up in the environment?
A team led by Joshua Cottom from the University of Leeds has now investigated these questions in detail for the first time. To do this, they used AI and computer models to evaluate available data on local material flows from 2020 and used this to determine the local and regional plastic waste in 50,702 cities and countries worldwide. This waste includes so-called macroplastics, i.e. all plastic particles larger than five millimeters. In theory, plastic of this size is easy to dispose of and recycle. If this does not happen, the plastic breaks down into microplastics over time.
The global inventory showed that around 52.1 million tonnes of plastic waste end up in the environment every year. This corresponds to 21 percent of the total plastic waste generated. Around 57 percent of the improperly disposed waste is burned on the street or in unofficial landfills without environmental regulations or pollutant filters, while the rest ends up largely unchanged in nature. The reasons for this are different: while waste in the global north is mainly created because it is carelessly thrown away, in the global south it accumulates because it is not collected and disposed of in a controlled manner. A total of 15 percent of the world’s population live without a garbage collection service, the researchers report. “At least 1.2 billion people have no access to garbage collection and are forced to ‘dispose of their garbage themselves’, often by disposing of it on land or in rivers or burning it in open fires,” says Cottom.
As a result, particularly large amounts of plastic waste are generated in poorer countries in South and Southeast Asia and in sub-Saharan Africa. However, the largest emitter of waste by far is India with 9.3 million tons of macroplastics per year – almost a fifth of the world’s plastic waste that is not disposed of in an environmentally friendly manner. Nigeria and Indonesia follow in second and third place with 3.5 and 3.4 million tons of macroplastics per year. China – identified as the main polluter in older analyses – is “only” in fourth place with 2.8 million tons. By comparison: In North America and most European countries the figure is less than 0.1 million tons, in Germany it is 7,725 tons per year.
Political action required
Policymakers could now use these findings to improve regional waste disposal and recycling so that less plastic waste ends up in the environment. “We need to focus much, much more on combating open burning and uncollected waste before even more lives are unnecessarily affected by plastic pollution,” says senior author Costas Velis from the University of Leeds. Waste disposal needs to be improved, particularly in poorer countries. The researchers are also calling for a global “plastics treaty” in which signatories commit to the proper and documented disposal of plastic in their country. This proposal is to be discussed at the upcoming UN Plastics Summit in South Korea in November.
Greenhouse gases and pollutants that are produced when waste is incinerated and can harm the climate or the reproduction and development of unborn children could also be partially reduced through better waste management. “But the inventory also underlines the fact that strategies for dealing with large pieces of plastic waste can increase emissions of other pollutants, including microplastics, dangerous air pollutants and greenhouse gases,” writes Matthew MacLeod of Stockholm University in a commentary on the study. He therefore advocates producing less plastic overall instead of just worrying about its disposal.
Source: University of Leeds; Nature, doi: 10.1038/s41586-024-07758-6