Plastic Pollution and the Great Pacific Garbage Patch


 Local oceanographer, Laurent ‘Lolo’ Lebreton - Head of Research at The Ocean Cleanup, spent three weeks sailing into the Great Pacific Garbage Patch (GPGP) earlier this year as part of his research into the state of plastic pollution in the ocean. This morning Lolo popped into the Raglan Community Radio to chat about his time out at sea.

“We sailed quite far into the Great Pacific Garbage Patch. We were doing a bunch of research - sampling at sea for plastic pollution, which was the main activity,” he said.

The Ocean Cleanup is an organisation that was founded by Boyan Slat in 2011 when he was 16-years-old after he saw more plastic than fish when he went diving off the coast of Greece. Boyan remained fascinated by the problem and continued working on his passive clean-up concept during high school and his freshman year at university. This eventually led him to start The Ocean Cleanup.

Lolo has previously worked at Artificial Surf Reefs (ASR) studying the dispersion of oil spills in the marine environment which evolved later into developing models to study plastic pollution. Publishing a study in 2012 modelling the amount of plastic pollution in the world’s oceans so they have “a clear, precise picture of what the patch looked like,” eventually led him to become the Chief Scientist on the Ocean Cleanup research vessel.


(Listen to the full interview below:)



When it comes to ocean waste, some might expect an island of rubbish when they visualise the garbage patch - but in reality the accumulation of plastic pollution looks like a vast space of ocean with bits of rubbish floating just beneath the surface level.

“If it was a trash island maybe it would be easier because we could just go in there with a bunch of cranes and pick up all that rubbish. But the problem is spread over millions of kilometres squared and it makes the problem very difficult to solve,” says Lolo, who these days, often refers to himself as a trash scientist instead of an oceanographer.

The large accumulation of rubbish at the Great Pacific Garbage Patch starts with the rotation of the earth which creates a natural circulation of sea surface currents - what we call gyres or rotating currents. There are five of these gyres around the world and they pull anything that is floating on the surface into an area like the GPGP - accumulating more rubbish over time.

During their survey of the GPGP, Lolo’s team have found remnants of plastic including buoys that date as far back as 1966 - although he highlights that they have to rely on finding clues on the plastic, like production dates, because there is no way to directly date plastic material.

Lolo also says that there is usually about a 10-year delay from when the plastic is produced to the time it ends up in the garbage patch. With the first plastics being mainly introduced around the end of the second World War, plastic production has been increasing exponentially throughout the past few decades. With an estimated 400 million tonnes of plastics produced each year, he says that we can expect to continue to see more plastic ending up in the ocean.

“The organisation I work for has a target to remove 90% of the accumulated plastic waste in the ocean by 2040,” says Lolo but he also points out that even if we stop all sources of plastic going into the sea we will still be cleaning up the oceans for a while.

When it comes to the business of cleaning-up, he says that catching all the pollution (including microplastics) is very hard to do; saying, “Our target is to collect anything over one cm squared,” and that catching plastic objects before they have a chance to break down into smaller sizes is key.

The effects of plastic pollution on the environment are numerous. Marine life can ingest plastic or become entangled in it. Non-native species can travel across the ocean on floating pieces of plastic to different habitats and affect biodiversity (if that species displaces the native species for example).

Microplastics also have an impact on plankton species that are involved in the ocean carbon sequestering process and could be impeding the natural process that stores carbon from the atmosphere into the sea - impacting climate change.

The proliferation of plastic material also means that plastics can be found throughout the food chain whether in tiny plankton or in large blue whales. 

“We’ve seen many pictures of whales stranded on the coastline and their guts are full of plastics and fishing nets and so on. But it’s not only whales, it's basically any species out there and why we talk about microplastics so much. Plastic is inert so it can just pass through the body but we have found traces of microplastic accumulating in tissue and blood - in human tissue as well.”

During their trip, Lolo and the team mapped the plastic by manually surveying patches of ocean as well as using remote sensing by mapping plastics using drones, taking footage of the surface of the ocean and using software to recognise how much plastic is found. The team are also developing methods of locating the plastic with the hope that citizen scientists will soon have a part to play by putting these systems on their own boats as they sail around the ocean.

Every single piece of plastic they find will be analysed and also compared to the information they find through their remote sensing data.

While cleaning up the ocean is their main purpose, Lolo and his team are trying to map the pollution to see where it’s coming from so that they can identify and stop the sources of ocean pollution to prevent future waste.

Most plastics originate from land so stopping the plastic from going into the ocean using things like river mouth interceptors can help to stop plastic ending up in the ocean in the first place.

Lolo says that while Ocean Cleanup’s family of river mouth interceptors around the world can help, the next step is to tackle plastic manufacturing. Plastic production globally is not slowing down with “billions of dollars in investment going in to create new plants,” so would need a global movement to address the issue.

“I think things are slowly moving,” says Lolo, citing the UN’s Environmental Assembly held earlier this year where leaders presented a resolution to create a legal agreement between nations to fight plastic pollution.

“It’s like Climate Change, we are aware of the problem, we’ve been aware for decades but we still push towards more plastic. It’s fixable but it requires policies and legislation. There's a few things we can do at a personal level but the solution needs to come from a higher institutional level.”

As a final thought, he says that it’s not necessarily about going against plastic but thinking about how we use it, like eliminating single use plastics - something the Raglan community has already started campaigning against.