Attempting to shine a light on the amount of plastic polluting our oceans, researchers from New Castle University turned their attention to crustaceans and other sea life residing in deep ocean trenches.

Looking at 90 different animals from trenches spanning the Pacific Ocean, including the Mariana, Japan, Izu-Bonin, Peru-Chile, New Hebrides and Kermadec trenches, researchers found evidence that not only is plastic waste reaching the deepest parts of our oceans, but also that the waste is being consumed by the creatures living there.

According to the team's findings, man-made materials — such as Rayon, Lyocell and Ramie (which are microfibers found in textiles), Nylon, polyethylene, polyamide and materials that closely resembled polyvinyl alcohol or polyvinylchloride — showed up in 50 percent of the animals tested from the New Hebrides Trench and appeared in 100 percent of the animals tested from the Mariana Trench.

"We published a study earlier this year showing high levels of organic pollutants in the very deepest seas and lots of people asked us about the presence of plastics, so we decided to have a look," said lead researcher Dr. Alan Jamieson.

Dr. Jamieson continued:

"The results were both immediate and startling. This type of work requires a great deal of contamination control but there were instances where the fibers could actually be seen in the stomach contents as they were being removed. We felt we had to do this study given the unique access we have to some of the most remote places on earth, and we are using these samples to make a poignant statement about mankind's legacy.

"The deep sea is not only the ultimate sink for any material that descends from the surface, but it is also inhabited by organisms well adapted to a low food environment and these will often eat just about anything.

"This study has shown that manmade microfibers are culminating and accumulating in an ecosystem inhabited by species we poorly understand, cannot observe experimentally and have failed to obtain baseline data for prior to contamination.

"These observations are the deepest possible record of microplastic occurrence and ingestion, indicating it is highly likely there are no marine ecosystems left that are not impacted by anthropogenic debris."

Dr. Jamieson adds: "Litter discarded into the oceans will ultimately end up washed back ashore or sinking to the deep-sea, there are no other options.

"Once these plastics reach the deep-seafloor there is simply nowhere else for them to go, therefore it is assumed they will simply accumulate in greater quantities.

"This is a very worrying find. Isolating plastic fibers from inside animals from nearly 11 kilometers deep (7 miles) just shows the extent of the problem.

"Also, the number of areas we found this in, and the thousands of kilometer distances involved shows it is not just an isolated case, this is global."

To contact the author of this article, email mdonlon@globalspec.com