Global map with each country shaded according to the estimated mass of mismanaged plastic waste [millions of tonnes (MT)] generated in 2010 by populations living within 50 km of the coast. Countries not included in the study are shaded white. From 'Plastic waste inputs from land into the ocean', Science 13 February 2015: Vol. 347  no. 6223  pp. 768-771. Graphic: Jambeck, et al., 2015

By Gwynn Guilford
13 February 2015 (Quartz) – Trillions of microscopic plastic bits litter the oceans of Earth, converging in huge trash vortexes before becoming lodged in the seabed and getting gobbled up by tiny fish. But since countries don’t report how much plastic they’re flushing, it’s been impossible to tell how much there is—or where it’s all coming from. This map from a groundbreaking new study (paywall) in Science finally gives us a sense of the biggest culprits—specifically which countries heap the most plastic into poorly managed coastal dumps or landfills. The study, led by Jenna Jambeck of the University of Georgia, estimates that between 15 and 40% of that precariously placed plastic is swept into the ocean via inland waterways, storm water or the wind. In 2010, between 4.8 million and 12.7 million tonnes (5.3 million-14 million tons) of plastic entered the sea. And as you can see from the map above, China likely contributed a hefty share of the total—nearly 28%. According to the authors’ forecasts, its share will fall only slightly by 2025. By then, China another other countries will flush as much as 28 million tonnes into the ocean each year—adding up to 155 million tonnes accumulated since 2010. The generally high share of plastic waste from China and other Asian countries is consistent with where scientists have found marine plastic debris, says Andrés Cózar, a marine ecologist at the University of Cadiz, who was not involved in the study. And this makes sense. Thanks to sprawling metropolises like Shanghai, Guangzhou, and Tianjin, China also has the biggest, densest coastal population on the planet. However, China’s plastic debris contributions don’t only come down to its huge size, says Daniel Hoornweg, associate professor at University of Ontario Institute of Technology and an expert in Asia’s waste management systems. “China generates a lot of garbage—per unit of GDP, more than India or Indonesia,” he says. (Though on a per capita basis, China generates less trash than the US). [more]

China is responsible for a quarter of the plastic clogging our oceans

ABSTRACT: Plastic debris in the marine environment is widely documented, but the quantity of plastic entering the ocean from waste generated on land is unknown. By linking worldwide data on solid waste, population density, and economic status, we estimated the mass of land-based plastic waste entering the ocean. We calculate that 275 million metric tons (MT) of plastic waste was generated in 192 coastal countries in 2010, with 4.8 to 12.7 million MT entering the ocean. Population size and the quality of waste management systems largely determine which countries contribute the greatest mass of uncaptured waste available to become plastic marine debris. Without waste management infrastructure improvements, the cumulative quantity of plastic waste available to enter the ocean from land is predicted to increase by an order of magnitude by 2025.

Plastic waste inputs from land into the ocean