July 1, 2014
Malaspina Expedition Finds World’s Oceans Littered With Microplastics
Brett Smith for redOrbit.com - Your Universe Online
The result of a 2010 ocean voyage around the world, a new study has found evidence of tiny “microplastics” in five large accumulations across the world -- accumulations that match the five large open-ocean currents called gyres.
According to the study, which was published in the Proceedings of the National Academy of Sciences, large amounts of these microplastics could be moving through the marine food chain or sinking to the ocean floor.
"Ocean currents carry plastic objects which split into smaller and smaller fragments due to solar radiation,” said study author Andrés Cózar, an aquatic ecosystem expert from the University of Cadiz in Spain. “Those little pieces of plastic, known as microplastics, can last hundreds of years and were detected in 88 percent of the ocean surface sampled during the Malaspina Expedition 2010.”
The expedition started on December 15, 2010 and involved over 400 researchers from around the world. Sponsored by the Spanish National Research Council (CSIC), the study team spent nine months studying changes occurring in the ocean ecosystem on a global scale.
On their journey, the researchers found two prolific plastics compounds in oceanic waters: polyethylene and polypropylene. These polymers are used in the manufacture of plastic bags, food and beverage containers, toys and other common items.
"These microplastics have an influence on the behavior and the food chain of marine organisms,” Cózar said. “On one hand, the tiny plastic fragments often accumulate contaminants that, if swallowed, can be passed to organisms during digestion; without forgetting the gastrointestinal obstructions, which are another of the most common problems with this type of waste. On the other hand, the abundance of floating plastic fragments allows many small organisms to sail on them and colonize places they could not access to previously. But probably, most of the impacts taking place due to plastic pollution in the oceans are not yet known.”
The study results provide evidence of these plastics outside the oceans’ most infamous region – the Great Pacific Garbage Patch in the northern Pacific Ocean.
"Our results show that the high concentration of plastic is not a unique feature of the North Pacific, but occurs in each of the subtropical gyres,” said Carlos Duarte, coordinator of the Malaspina Expedition. "Only a global expedition, such as the Malaspina Expedition, could achieve these results and evaluate the overall abundance of plastic pollution. The good news is that abundance is much lower than expected, but the pending challenge is to figure out where the rest of plastics entering the ocean is.”
In addition to gathering information on plastics in the ocean, the expedition also tested water, plankton, atmosphere particles and gas samples in 313 points of the Indian, Pacific and Atlantic Oceans.
Kara Lavender Law, a plastics pollution expert the Sea Education Association in Massachusetts, told the Associated Press that the new study offers the first global estimate for floating plastic trash. She added the study team’s estimate appears to be correct based on findings of previous similar efforts.
"We are putting, certainly by any estimate, a large amount of a synthetic material into a natural environment," Law said. "We're fundamentally changing the composition of the ocean."