MICHAEL PHELAN, a famous billiards1 player and supplier2, lamented3 in 1858 that the growing popularity of the game had made the ivory4 needed for the balls scarce and costly. “If any inventive 5genius would discover a substitute”, he wrote, “he would make a handsome fortune for himself, and earn our sincerest gratitude6.” Five years later, Phelan’s company offered a reward of $10,000 (about$250,000 today) for anyone who could do just that. The result, after some tinkering7, was celluloid—the world’s first major synthetic plastic.

Though he never claimed the prize, John Hyatt, the inventor, was indeed richly rewarded. Ever since, the world has had an almost insatiable 8hunger for plastics. This is because plastics’ structure—made up of repeating molecular 9units called monomers, which can be combined and arranged in an enormous 10variety of ways to form polymers—meant that they could be used to replicate the properties of almost any other material. They could also improve on it: becoming lighter, more durable11, cheaper or easier to manufacture.

Their impact has been stunning12. The ability to ship goods much more efficiently—and perishables13 more safely—allowed supply chains to stretch 14across borders, then oceans. In 2000 some 234m tonnes of plastic were produced. By 2021 annual production had roughly 15doubled, with the trade in plastics (and goods containing it) estimated to be worth $1.2trn16 each year.

Without plastics the modern world would look decidedly 17different. Plastic packaging is significantly lighter than other materials—the weight of a one-litre18 plastic bottle is just 5% that of a glass one; a paper bag is nearly six times heavier than a plastic one (and takes three times as much energy to produce). Using cans or glass bottles for soft drinks results in greenhouse-gas emissions two and three times higher respectively than using plastic, even taking recycling into account.

Lightweight, airtight 19plastic containers allow luxuries like Argentine beef to be sold cheaply in British supermarkets. But they also facilitate 20the transport and storage of essentials 21like rice, cooking oil and powdered milk in poor countries, where refrigeration is scarce 22and roads are poor. Doing away with them would make global trade so much more fuel-intensive and expensive that much of it might disappear.

Other industries would suffer, too (see chart 1). In construction, PVC pipes and plastic-based insulation 23materials have reduced the cost of building and maintaining homes, making housing more affordable. Plastic casings and circuit 24components are needed to make mobile phones, laptops and fibre-optic cables. In health care, single-use plastic syringes 25and protective equipment, such as gloves and masks, are crucial for infection control.

But all those gains have come at a cost. The production of plastics, which generally involves breaking down fossil fuels into their constituent 26hydrocarbon building blocks, such as ethylene and propylene, releases lots of carbon dioxide. The production and disposal 27of plastics is currently responsible for around 3.4% of the world’s annual greenhouse-gas emissions, more than the aviation 28industry’s 2.5%.

Then there is what happens to the 350m tonnes that are thrown away each year. Roughly 50% of plastic waste ends up in landfills. This is less environmentally ruinous than widely thought, as long as they are properly built and managed to prevent harmful chemicals (like those used in flame retardants) and microplastics from leaching out and contaminating 29the surrounding soil and water, or gases such as methane 30from escaping to the atmosphere.

The problem is collecting the waste in the first place. McKinsey reckons that 95% of all the plastics used in packaging (itself roughly 30% of the total plastic produced by volume) are disposed 31of after just one use. Of this, a third is never collected at all. Instead, it litters 32the natural environment and clogs up33 ecosystems (see chart 2).

In recent decades alarm has been growing about how exposure to the elements34, particularly within the oceans, causes plastic litter to break down into minuscule 35“microplastics”, and even smaller “nanoplastics”. These enter the food chain, including sources such as table salt, and wind up36 in various parts of human bodies.

It is unclear exactly how damaging this is to people, not least because a large proportion 37of the thousands of chemicals found in plastics have not been assessed for health risks. But worries are growing that plastics may cause irreversible 38health effects. These have been intensified 39by the finding that microplastics trigger inflammation40, the basis for many chronic diseases.

Possible health risks have generated a renewed focus on where much of the world’s plastic waste ends up, and have led to a growing number of countries adopting ambitious recycling targets. The EU, for example, wants to recycle 55% of all plastic packaging by 2030.

Yet only 9% or so of used plastic is ever turned into something else, up from 4% in 2000. In part, that is because even well-intentioned41 people often slip up when trying to recycle: you can contaminate an entire batch when binning 42the wrong sort of plastic. And the chemical diversity that makes plastics so wildly useful also makes it hard to turn one type into another. No amount of washing, shredding 43or melting will turn polystyrene (used for takeaway containers and packaging inserts) into PET (used for drinks bottles and some food trays). Many additives, such as colouring dyes44, can make plastic entirely unrecyclable.

Moreover, no plastic can be recycled indefinitely45. Each time it is broken down it loses some of its structural integrity. That means most do not become another version of the object they once were. Instead they are turned into something with lower-quality requirements—a drinks bottle becomes the filling used in jackets or carpets46, for example. After two or three cycles, most plastic becomes so degraded 47that it is no good for anything. Yet recycling is so expensive that used stuff is sometimes more expensive than its virgin predecessor48.

Dealing with plastic waste is arduous49, grubby 50and not very lucrative51, which means that a good deal of this work happens in poor countries. The UN estimates that 2% of all plastic waste is exported for processing, though others think the actual figure is far higher. In the past almost all of the West’s plastic waste went to China. In 2018, however, worries about the impact of pollution and contamination led the country to, in effect, ban imports of rubbish from abroad. For a few years, chaos ensued as waste was rerouted 52to places such as Malaysia, Indonesia and Vietnam—many of which lacked the infrastructure to manage it safely (or at all). Plastic piled 53up at ports, was dumped or burned illegally, or processed in inadequate facilities, often exposing workers and local communities to toxic fumes 54and contaminated water.

In 2021 the EU revised 55its waste shipment rules to permit exports of plastic waste only to other OECD countries. Almost 40% of the bloc’s trash now ends up in Turkey, which jumped at the chance of a business to bolster 56its ties with the rest of Europe and, crucially, see it paid in euros. (The EU’s announcement came shortly before Recep Tayyip Erdogan, Turkey’s president, declared he would ban waste plastic imports—a decision hastily reversed.) But, explains Krista Shennum, who investigated the Turkish waste industry for Human Rights Watch, an NGO, the country has done little to ensure that the plastic is dealt with safely. Workers are often undocumented migrants (sometimes children), many of whom endure dreadful 57working conditions and huge amounts of chemical exposure. The UN reckons 58roughly 59% of all waste plastic worldwide ends up being sorted by some 20m informal workers.

Such unintended consequences have led to calls for countries to agree on how to deal with plastics. A study in 2023 concluded that, with the right mix of policies, it should be possible to reduce the annual volume of plastic that is “mismanaged” (neither recycled nor disposed of correctly) by 90% by 2040. The rub59, of course, is that the policies needed would have to be instituted 60everywhere and be incredibly wide-ranging. These span 61from levying fees on virgin plastic to banning all avoidable single-use plastics. Global rules would be needed to enact 62them.