A plastic bag drifting under the sea surface.
Blue Initiative

Plastic pollution

Every piece of plastic ever made that has not been burned still exists, somewhere on this planet. Most of it will outlive everyone reading this sentence.

Plastic is a miracle material. It is light, cheap, waterproof and almost indestructible, which is exactly why we use it for everything from medical syringes to crisp packets, and exactly why it has become a problem. The same chemical bonds that make a bottle strong make it last for centuries once it is thrown away. Nature has no enzyme that evolved to eat it quickly.

Why plastic persists

Most plastics are long chains of carbon and hydrogen made from oil and gas. Sunlight and waves do break them, but not into anything harmless: a bottle splits into fragments, the fragments into microplastics smaller than five millimetres, and those into nanoplastics too small to see. Microplastics have now been found from the deepest ocean trenches to Arctic snow, in fish, in drinking water and in human blood.

Hundreds of small white, blue and yellow plastic pellets scattered among twigs and grass on a beach.
Nurdles, the small plastic pellets from which most plastic products are made, washed up among beach debris. Spilled pellets are one of the sources of microplastics in the sea. Photo: hockadilly, CC BY-SA 2.0

How it reaches the sea

Only a small share of the world’s plastic is recycled. According to the OECD, the world made about 460 million tonnes of plastic in 2019 and threw away 353 million tonnes. Just 9 percent of that waste was recycled; 22 percent was mismanaged, meaning dumped, burned in the open or lost to the environment. Rivers are the highways: plastic dropped on land is washed into drains, drains into rivers and rivers into the sea.

460 Mtplastic produced in 2019 (OECD, 2022)
9%of plastic waste was recycled (OECD, 2022)
19 to 23 Mtof plastic waste entered rivers, lakes and seas in 2016 (Borrelle et al., 2020)

Wealthy regions are not immune. The Mediterranean holds about 1 percent of the world’s sea water but about 7 percent of its microplastics, and plastic makes up 43 to 51 percent of the litter on Greek beaches (WWF, 2018). Our water pollution explainer ranks the rivers that carry the most plastic to the sea and shows how it persists in Europe’s rivers and seas too.

A beach strewn with plastic nets, buoys, bottles and crates below a bare volcanic mountain, with a lone figure standing on the rubbish.
Plastic washed up on Santa Luzia, an uninhabited island of Cape Verde, in 2021. Winds and Atlantic currents gather it on the north of the island; much of it is lost fishing gear. Photo: CaptainDarwin, CC BY-SA 4.0

Fishing gear is a special case. Lost and abandoned nets, lines and traps keep catching fish, turtles, seals and seabirds for years, a problem known as ghost fishing, and they make up a large share of the floating plastic in the great ocean gyres.

A sea turtle caught in a tangle of green fishing net on a rocky shore.
A sea turtle entangled in a ghost net, a lost or abandoned fishing net that keeps on catching. Credit: NOAA

Recycling is the last line of defence. The first is not making the waste at all.

The invisible part: additives

A plastic product is rarely pure polymer. Manufacturers add plasticisers, flame retardants, colourants and stabilisers, and some of these chemicals can leach out. Some, such as certain phthalates and bisphenols, interfere with hormones and are restricted in a number of countries. The science on their full effects at everyday exposures is still developing, which is itself a reason for caution.

Proven solutions

The evidence points to measures that act before plastic becomes waste, and several of them have already worked at national scale:

  1. Charge for single-use bags, or ban them. England’s charge on single-use carrier bags, introduced in 2015, has been one of the fastest behaviour changes on record: the main supermarkets handed out 7.6 billion single-use bags in 2014, and sold 126 million in 2025 to 2026, a fall of 98 percent (UK government). Ireland introduced a 15 cent levy on plastic bags in 2002, and the money goes to projects that reduce waste; the share of plastic bags in Irish litter has fallen by more than 92 percent since then (Government of Ireland; Convery et al., 2007). Rwanda banned plastic bags outright in 2008 and has enforced the ban so well that it is widely praised as a regional leader (Behuria, 2021).
  2. Deposit return. Paying a small refundable deposit on bottles and cans turns empty containers into money, so they come back instead of reaching rivers. In Norway, 92.4 percent of deposit plastic bottles were returned for their deposit in 2025, and 98.2 percent were collected in total (Infinitum annual report 2025). Lithuania started its scheme in 2016: about a third of plastic bottles were collected before it, and 91.9 percent of all deposit containers came back by the end of 2017, only the scheme’s second year, according to the operator’s figures (Open Access Government, 2018). In Germany, single-use bottles and cans also carry a deposit, and since 2006 every shop that sells them must take back empties of the same material (DPG).
A bottle and can return machine set into a tiled wall in a Norwegian supermarket, under a red sign reading Miljøstasjon.
A return machine for bottles and cans in a Coop Extra supermarket at Osøyro, Norway, in 2018. Each container fed into it pays back its deposit. Photo: Wolfmann, CC BY-SA 4.0
  1. Make producers pay. Extended producer responsibility schemes charge companies for the collection and recycling of the packaging they sell, which pushes them to use less and design for recycling. The case is backed by data: a study of 1,576 brand audits by volunteers in 84 countries found that a company’s share of branded plastic pollution rises in direct proportion to its share of plastic production, and that half of all items carried no brand at all, a reason to make producers report what they sell (Cowger et al., 2024).
  2. Collect everything. For billions of people there is no waste collection at all. Building basic collection and sorting is the single biggest lever for stopping plastic reaching the sea.
A young man with a bicycle loaded with a large black sack of collected plastic stands on a rubbish dump under a cloudy sky.
A waste picker with a sack of collected plastic. In many countries, informal collectors like him gather much of the plastic that is recycled. Photo: Andrew Kartende, CC BY-SA 4.0
  1. A global treaty. United Nations member states have been negotiating a legally binding treaty to end plastic pollution across the whole life cycle of plastic, from production to disposal.

The pattern is clear. When the cheapest and easiest choice is also the clean one, most people take it, and the change is fast.

Organisations doing this work

These non-profits have a public record of results. Take a look at what they do, and if their work speaks to you, consider donating to them directly through their own websites. The Local Solar System Foundation has no affiliation with any of them and receives nothing from them. Before you give, read each organisation’s latest annual report and accounts, as you would with any charity.

  • Ocean Conservancy is a US non-profit (501(c)(3)) that runs the International Coastal Cleanup. Since it began, more than 19 million volunteers have collected over 400 million pounds (about 180,000 tonnes) of rubbish, and recorded every item on standard data cards, building the world’s largest database of marine litter (Ocean Conservancy).
  • 5 Gyres Institute is a US non-profit (501(c)(3)) founded by researchers Marcus Eriksen and Anna Cummins. Eriksen led the study that made the first global estimate of floating ocean plastic, more than 5 trillion pieces (Eriksen et al., 2014), and the institute led the #BanTheBead campaign that helped pass the United States’ Microbead-Free Waters Act of 2015.
  • Plastic Soup Foundation is a Dutch charity with public-benefit (ANBI) status, founded in 2011. It campaigns for EU and global rules on plastic, runs an app that lets shoppers scan cosmetics for microplastics, and helped start the first research into the health effects of microplastics in 2018.
A sea turtle swimming beside a floating plastic bag.
Sea turtles can mistake floating bags for jellyfish, one of their natural foods.

How you can help

  • Refuse, then reuse. Carry a bottle, a cup and a bag. The most effective plastic is the one never made.
  • Buy loose and refill. Choose loose fruit and vegetables, refill shops and products in glass, metal or paper where they make sense.
  • Avoid what cannot be recycled: black plastic trays, multi-layer pouches, polystyrene and anything labelled compostable when your area has no industrial composting.
  • Watch out for microplastics at home. Wash synthetic clothes less often, fuller and cooler, and consider a washing machine filter; avoid cosmetics with plastic microbeads.
  • Pick up three. Take three pieces of litter from a beach, a park or a riverbank every time you visit. It adds up.
  • Ask your town and your shops. Ask for deposit-return schemes, public water fountains and refill options. Ask brands to publish how much plastic they sell and how much they collect.
  • Join us. Help translate this explainer or map local plastic data on the contribution board.

Sources and further reading