A floating plastic in the ocean
A diver removes plastic in the ocean

- Rich Carey

New study finds that the amount of plastic debris found in our oceans is much less than previously estimated.

But is this good or bad news?

A new study, by Cozar et al, and published by PNAS.org, finds that plastic debris is more widespread in the world’s oceans than previously believed, but at the same time that there is far less of it than estimated in other studies of pollution of our oceans.

The study, the first of its kind, used primary data collected from a research ship which, during a worldwide cruise, trawled for plastic debris on the surface of a total of 141 sites.

This was then correlated with a number of other studies.

The results were surprising.

Bad News for who?

The obviously bad news first: plastic debris is much more common on the surface of the world’s oceans than we previously thought.

The occurrence of plastic debris in oceans has seen a significant amount of press coverage lately, with the majority of it focusing on a few select sites, such as the infamous Great Pacific Garbage Patch.

This has given some people the impression that the plastic we deposit in the oceans, by mistake or intent, is rounded up by currents and finds it way to a few select sites.

This turns out to be erroneous, the new study says, as plastic debris was found to be very widespread.

Floating plastic in the ocean

Not all floating plastic in the ocean gets rounded up by the current - Credit: Rich Carey

This is obviously not good, as it indicates that we cannot solve the problem of plastic in our oceans by focusing on cleaning up a few select sites, as has been proposed by some.

Instead, we need to focus on widespread cleanups, as well as legislation to limit the source of the plastic.

Read this article to learn more How To Become An Environmentally Safe Diver.

The other, and more surprising, result was that there may not be anywhere near as much plastic in the oceans as previously estimated.

Estimations based on data from the 1970s put the amount of plastic debris in the open oceans at 1 million tons, but the new study puts it closer to the range of 7,000 to 35,000 tons.

This figure seems low, considering what we know of plastic use and discarding, so the question is why the figure is that much lower than expected.

A cat and christmas tree add plastic in the ocean

Surprisingly a cat and a Christmas tree underwater

Is this good or bad news

It may be that it is simply good news: the situation isn’t as bad as we had feared, though up to 35,000 tons of plastic is still too much, and more than enough to pose a threat the health and wellbeing of our oceans and the creatures in them.

On the other hand, there may be something else in play.

Maybe the amount of plastic that finds its way to the oceans is around the 1 million tons as estimated, but the majority of it sinks to the bottom (the study only focused on debris floating in the surface), causing other problems than we’ve thought so far, and being much harder to clean up.

This hypothesis is supported by the fact that few large pieces were found in the study, which may indicate that the larger, heavier pieces sink.

Also, the amount of small debris was less than expected, leading the researchers to speculate that the smallest debris pieces are being consumed by fish and other marine animals, causing unknown consequences to their health, and the health of their populations.

A sunk plastic in the ocean

Like this rubber tire, the larger and heavier pieces sink - Credit: Darren J. Bradley


With this new insight, and the questions it raises, more studies of the state of our oceans are greatly needed, in particular focusing on the worldwide problem of plastic debris.

Only by gaining more knowledge can hope to solve the problem, for the benefit of the oceans, their inhabitants, and us, whether we are scuba divers, marine biology enthusiasts, or any other occupation.

Do you know How Can Scuba Divers Make A Difference For The Environment?

For the health of the oceans concerns us all. Without living, healthy oceans, there is little chance for life on the rest of the planet.