The world’s plastic pollution crisis, explained

Plastic pollution has become one of the most pressing environmental issues, thanks to the overwhelming rise in production of disposable Plastic products.

Plastic pollution is most visible in developing Asian and African nations, where garbage collection systems are often inefficient or nonexistent. But the developed world, especially in countries with low recycling rates, also has trouble properly collecting discarded plastics.

(With Millions of Tons of Plastic in Oceans, More Scientists Studying Impact)

Plastic trash has become so ubiquitous it has prompted efforts to write a global treaty negotiated by the United Nations.

Why was plastic invented?

Plastics made from fossil fuels are just over a century old. Belgian chemist Leo Baekeland created the first fully synthetic plastic in . Production and development of thousands of new plastic products accelerated after World War II, which transformed the modern age so much that life without plastics would be unrecognizable today. In plastic, inventors found a light, durable material that can be used in everything from transportation to medicine.  

Plastics revolutionized medicine with life-saving devices, made space travel possible, lightened cars and jets—saving fuel and pollution—and saved lives with helmets, incubators, and equipment for clean drinking water.

The conveniences plastics offer, however, led to a throw-away culture that reveals the material’s dark side: today, single-use plastics account for 40 percent of the plastic produced every year. Many of these products, such as plastic bags and food wrappers, have a lifespan of mere minutes to hours, yet they may persist in the environment for hundreds of years.

(Four innovative ideas helping to fix the plastic problem)

That's why some governments have taken steps to limit or ban the use of plastic bags. Most recently, California passed legislation to ban all plastic bags by .

Plastics by the numbers

Here are a few key facts:

• Half of all plastics ever manufactured have been made in the last 20 years. Production increased exponentially, from 2.3 million tons in to 448 million tons by . Production is expected to double by .
• Every year, about eight million tons of plastic waste escapes into the oceans from coastal nations. That’s the equivalent of setting five garbage bags full of trash on every foot of coastline around the world.
• Plastics often contain additives making them stronger, more flexible, and durable. But many of these additives can extend the life of plastic products if they become litter, with some estimates ranging to at least 400 years to break down.

How plastic pollution spreads around the world

Most of the plastic pollution in the oceans, Earth’s last sink, flows from land. Trash is also carried to sea by major rivers, which act as conveyor belts, picking up more and more trash as they move downstream.

Once at sea, much of the plastic trash remains in coastal waters. But once caught up in ocean currents, marine plastic pollution can spread around the world.

The South Pacific gyre, a circular ocean current, carries plastic pollution to Henderson Island, an uninhabited atoll in the isolated Pitcairn Group located halfway between Chile and New Zealand. There, scientists have found plastic items from Russia, the United States, Europe, South America, Japan, and China.

(Eight Million Tons of Plastic Dumped in Ocean Every Year)

How microplastics affect our health

Once in the ocean, sunlight, wind, and wave action break down marine plastic pollution into small particles, often less than one-fifth of an inch across.

(Learn more about the microplastics in our bodies and how much they harm us)

These so-called microplastics spread throughout the water column and have been found in every corner of the globe, from Mount Everest, the highest peak, to the Mariana Trench, the deepest trough.

Microplastics are breaking down further into smaller and smaller pieces. Meanwhile, plastic microfibers have been found in municipal drinking water systems and drifting through the air.

It’s no surprise that scientists have found microplastics in people. The tiny particles are in our blood, lungs, and even in feces. Exactly how much microplastics may be harming human health is a question scientists are urgently trying to answer.

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How plastic pollution harms wildlife

Millions of animals are killed by plastics every year, from birds to fish to other marine organisms. Nearly 2,100 species, including endangered ones, are known to have been affected by plastics. Nearly every species of seabird eats plastics.

Most of the deaths to animals are caused by entanglement or starvation. Seals, whales, turtles, and other animals are strangled by abandoned fishing gear or discarded six-pack rings. Microplastics have been found   in more than 100 aquatic species, including fish, shrimp, and mussels destined for our dinner plates.

In many cases, these tiny bits pass through the digestive system and are expelled without consequence. But plastics have also been found to block digestive tracts or pierce organs, causing death. Stomachs packed with plastics reduce the urge to eat, causing starvation.

Plastics have been consumed by land-based animals, including elephants, hyenas, zebras, tigers, camels, cattle, and other large mammals, in some cases causing death.

Tests have also confirmed liver and cell damage and disruptions to reproductive systems,   prompting some species, such as oysters, to produce fewer eggs. New research shows that larval fish are eating nanofibers in the first days of life, raising new questions about the effects of plastics on fish populations.

Stopping plastic pollution

Once in the ocean, it is difficult—if not impossible—to retrieve plastic waste. Mechanical systems, such as Mr. Trash Wheel, a litter interceptor in Maryland’s Baltimore Harbor, can be effective at picking up large pieces of plastic, such as foam cups and food containers, from inland waters.