The study is entitled ‘Plastic waste inputs from land into ocean’. It has been produced by the National Centre of Ecological Analysis and Synthesis (NCEAS) Working Group.

According to the NCEAS, until now, researchers have not had a firm grasp of the amount of plastic that makes its way from land to sea each year.

The group analysed waste production data from 192 countries to conclude that in 2010 between 4.8m and 12.7m tonnes of “mismanaged plastic” entered the oceans; 8m is the central estimate.

Plastic in the oceans is becoming a problem for marline life. When in the sea, plastics can also absorb toxic chemicals, becoming increasingly harmful over time, and often entering the food chain when mistaken for food items by fish, seabirds or marine mammals. Plastic debris can also be found littering coastlines all across the world’s oceans, even on the most far-flung and inaccessible of beaches.

‘Mismanaged plastic waste’
The research, which also appears in the journal Science, lists the world’s 20 biggest national sources of mismanaged plastic waste. China comes out on top (28%), followed by Indonesia (10%) and the Philippines. The US is number 20. The UK does not feature in the top 20.

Speaking about the report, University of Georgia study leader Jenna Jambeck said: “Our estimate of 8m metric tonnes going into the oceans in 2010 is equivalent to five grocery bags filled with plastic for every foot of coastline in the world. This annual input increases each year, so our estimate for 2015 is about 9.1m metric tonnes.”

“In 2025, the annual input would be about twice the 2010 input, or ten bags full of plastic per foot of coastline. So the cumulative input by 2025 would equal 155m metric tonnes.

“Our mismanaged waste is a function of both inadequate management – open dumping, for example – and litter. This mismanaged waste goes uncaptured, meaning that it then becomes available to enter marine environments.”

Jambeck said that nations around the world needed to reduce their overall waste and adopt better management strategies to prevent plastic debris reaching the oceans. She added: “Solutions will require a combination of local and global efforts.”

PlasticsEurope, the association of plastics manufactures in Europe, said that it welcomed the study. In a statement, the organisation said the European plastics industry was taking the issue of marine litter “seriously”.

“In 2011, the European plastics industry launched the initiative ‘Zero Plastics to Landfill’, which aims at reducing the amount of post-consumer plastics waste sent to landfills to zero,” said PlasticsEurope executive director Karl-H Foerster.

He added: “Seven EU member states plus Norway and Switzerland introduced landfill bans or similar measures applicable to plastics waste.The experience of these nine countries shows that phasing out landfilling together with a better implementation and enforcement of existing waste legislation is crucial to tackle this issue.”

Liz Gyekye

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