It turns out our pristine oceans, filled with all sorts of colorful marine life, corals and plankton, are riddled with 8 million metric tons of plastic.
Reported in the journal Science, discarded beverage bottles, food wrappers, toys and other bits of plastic are finding their way from estuaries, seashores and uncontrolled landfills and settling in the world's seas.
This poses obvious threats to various marine creatures. Plastics are deadly to whales and dolphins, for example, seabirds, and can even harm freshwater organisms too.
Plastic didn't become popular until the 1930s and '40s, and until waste management practices were implemented in the mid-1970s, this trash was dumped in unstructured landfills and could easily pollute Earth's oceans. Now, estimates show that in 2010 alone, between 4.8 and 12.7 million metric tons of plastic (8 million metric tons is the midpoint) entered the ocean from people living within 50 kilometers (31 miles) of the coastline.
And that year, a total of 275 million metric tons of plastic waste was generated in the 192 studied coastal countries.
"For the first time, we're estimating the amount of plastic that enters the oceans in a given year," study co-author Kara Lavender Law said in a statement. "Nobody has had a good sense of the size of that problem until now."
"Eight million metric tons is the equivalent to finding five grocery bags full of plastic on every foot of coastline in the 192 countries we examined," added the University of Georgia's Jenna Jambeck, who led the study.
To determine the amount of plastic going into the ocean, Jambeck and her colleagues developed models for all the debris entering the ocean from land, sea and other pathways. What they found was that mismanaged waste and solid waste were the biggest contributors.
"It is incredible how far we have come in environmental engineering, advancing recycling and waste management systems to protect human health and the environment, in a relatively short amount of time. However, these protections are unfortunately not available equally throughout the world," Jambeck explained.
And as of right now, the generation of plastic does not seem to be stopping anytime soon. If anything, it will only continue to rise.
Based on the results, the cumulative impact to the oceans will equal 155 million metric tons by 2025. The planet will reach a global "peak waste" after 2100, according to World Bank calculations.
"We're being overwhelmed by our waste," Jambeck said. "But our framework allows us to also examine mitigation strategies like improving global solid waste management and reducing plastic in the waste stream. Potential solutions will need to coordinate local and global efforts."
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