Healing the Plastic-Sick Seas

The Ocean Cleanup system, the first scalable solution to prevent plastic from entering the world’s oceans from rivers, is 100 percent solar-powered, extracts plastic autonomously, and can be placed in the majority of the world’s most polluting rivers. Here it is shown on Malaysia’s Klang River. (Photo courtesy The Ocean Cleanup) Posted for media use

By Sunny Lewis

LONDON, UK, November 26, 2019 (Maximpact.com News) – More than 300 million tons of plastic are produced annually around the world, yet less than 10 percent of all plastic is recycled. Instead, at least eight million metric tons of plastic are dumped into the oceans each year, equal to a garbage truck every minute.

A 2017 study estimates that more than a quarter of all this plastic waste enters the oceans from just 10 rivers, eight of them in Asia.

“Rivers carry trash over long distances and connect nearly all land surfaces with the oceans,” making them a major battleground in the fight against sea pollution, explains Christian Schmidt, a hydrogeologist at the Helmholtz Center for Environmental Research in Leipzig, Germany.

Schmidt and his colleagues collected published data on the plastic concentration in 57 rivers around the world. The measurements included bottles, bags, microscopic fibers and beads. The results, published in the journal “Environmental Science & Technology,” show that rivers collectively pour up to 2.75 million metric tons of plastic into the seas every year.

The 10 rivers that carry 93 percent of that plastic debris are the Yangtze, Yellow, Hai, Pearl, Amur, Mekong, Indus and Ganges Delta in Asia, and the Niger and Nile in Africa. The Yangtze River alone dumps up to an estimated 1.5 million metric tons of plastic waste into the Yellow Sea.

Plastic pollution in the world’s oceans is one of the biggest environmental issues of our time, affecting more than 600 marine species.

Microplastics in the marine environment originate from a variety of sources – fragmentation of larger waste plastics, pre-production pellets (nurdles) spilled during transportation and fabrication, outflow of wastewater containing microbeads from cosmetics and fibers from the washing of synthetic textiles, as well as road run-off containing fragments of vehicle tires and marking paint.

Annual economic costs due to marine plastic pollution are estimated to be between US$6-19 billion, according to a study conducted by the Dutch nonprofit Ocean Cleanup in collaboration with the multinational financial services firm Deloitte as part of a three-year partnership between the two organizations that ends next September.

The costs stem from the plastic’s impact on tourism, fisheries and aquaculture, and governmental cleanups.

Plastic pollution does not only impact sea life, it also carries toxic pollutants into the food chain that ultimately includes humans.

A large percentage of the plastic that enters the oceans, drifts into giant systems of circulating ocean currents, known as gyres. Once trapped in a gyre, the plastic will slowly break down into microplastics and become increasingly easier for sea life to mistake for food.

And marine mammals do eat these tiny beads of plastic. Microplastics were found in the guts of every marine mammal examined in a study of animals washed up on Britain’s shores, published earlier this year.

Researchers from the University of Exeter and Plymouth Marine Laboratory examined 50 animals from 10 species of dolphins, seals and whales – and found microplastics, defined as less than 5mm in diameter, in them all.

The species examined in this study were: the Atlantic white-sided dolphin, bottlenose dolphin, common dolphin, grey seal, harbour porpoise, harbour seal, pygmy sperm whale, Risso’s dolphin, striped dolphin and white-beaked dolphin.

Most of the particles, 84 percent, were synthetic fibers from clothes, fishing nets and toothbrushes. The rest were fragments, whose possible sources include food packaging and plastic bottles.

“It’s shocking, but not surprising, that every animal had ingested microplastics,” said lead author Sarah Nelms, of the University of Exeter and Plymouth Marine Laboratory.

“We don’t yet know what effects the microplastics, or the chemicals on and in them, might have on marine mammals,” said Nelms. “More research is needed to better understand the potential impacts on animal health.”

The paper, published in the journal “Scientific Reports,” is entitled, “Microplastics in marine mammals stranded around the British coast: ubiquitous but transitory?”

Dr. Penelope Lindeque, who heads the Marine Plastics research group at Plymouth Marine Laboratory, said, “From our work over the years we have found microplastic in nearly all the species of marine animals we have looked at, from tiny zooplankton at the base of the marine food web to fish larvae, turtles and now dolphins, seals and whales.”

“We don’t yet know the effects of these particles on marine mammals,” Lindeque said. “Their small size means they may easily be expelled, but while microplastics are unlikely to be the main threat to these species, we are still concerned by the impact of the bacteria, viruses and contaminants carried on the plastic.”

“This study provides more evidence that we all need to help reduce the amount of plastic waste released to our seas and maintain clean, healthy and productive oceans for future generations,” she said.

The study, supported by Greenpeace Research Laboratories, used samples provided by the Scottish Marine Animal Stranding Scheme, Cornwall Wildlife Trust’s Marine Stranding’s Network and the Zoological Society of London’s Cetacean Strandings Investigation Programme (CSIP).

Many other groups are studying the plastic marine debris problem.

The nonprofit Plastic Oceans International announced that from November 29 to December 8 Global Executive Director Julie Andersen will join Leg 4 of eXXpedition Round the World, a two-year, all-female sailing voyage to investigate the causes of, and solutions to ocean plastic pollution.

“I look forward to conducting further research into the science behind plastic pollution’s impact on human health, and particularly female health, represented by XX in eXXpedition, to find solutions,” said Andersen.

“Data show plastic pollutes the oceans and environment at an alarming rate, and it’s essential to rethink plastic use and management. Individuals, communities, companies and governments must collaborate to pass local and global laws that incentivize producer responsibility, eliminate single-use plastic products, require plastic packaging to be replaced with sustainable materials, and require producers to design essential plastics for efficient and effective reuse, recycling or compost.”

Possible Solutions

Dutch inventor Boyan Slat founded the nonprofit organization The Ocean Cleanup at the age of 18 in his hometown of Delft, the Netherlands.

Now based in Rotterdam, today the Ocean Cleanup’s team consists of more than 80 engineers, researchers, scientists and computational modelers working daily to rid the world’s oceans of plastic.

In October, Slat announced that his System 001/B was successfully capturing and collecting plastic debris. After one year of testing, the group has succeeded in developing a self-contained system in the Great Pacific Garbage Patch using the natural forces of the ocean to passively catch and concentrate plastic, confirming the most important principle behind the cleanup concept that was first presented by Slat at a TEDx conference in October 2012.

Going after the plastic in the garbage patches with vessels and nets would be costly, time-consuming, labor-intensive, and lead to vast amounts of carbon emission and by-catch, says Slat. Instead, The Ocean Cleanup is developing a passive ocean cleanup technology, that moves with the currents, just like the plastic, to catch it.

By deploying a fleet of systems, The Ocean Cleanup has estimated it will be able to remove 50 percent of the Great Pacific Garbage Patch every five years. It is Slat’s ultimate goal to reach a 90 percent reduction of floating ocean plastic by the year 2040.

The Ocean Cleanup system is 100 percent solar-powered, extracts plastic autonomously, and can be placed in the majority of the world’s most polluting rivers. Together with corporations and governments from all over the world, we plan on tackling 1,000 of the most polluting rivers all over the world in the next five years.

Launched from Vancouver in June, System 001/B is The Ocean Cleanup’s second attempt to prove its concept of collecting garbage from the Great Pacific Garbage Patch, the largest accumulation zone of plastic in the world’s oceans.

The aim of System 001/B was to try modifications aimed at correcting the speed difference between the system and the plastic. Consistency was achieved by slowing down the system with a parachute sea anchor, allowing for faster-moving plastic debris to float into the system.

In addition to collecting plainly visible pieces of plastic debris, as well as much larger ghost nets associated with commercial fishing, System 001/B has also successfully captured microplastics as small as one millimeter.

The Ocean Cleanup will now begin to design its next ocean cleanup system, System 002; a full-scale cleanup system that is able to both endure and retain the collected plastic for long periods of time. Once fully operational, The Ocean Cleanup will return plastic to land for recycling. The timing of that phase of the mission is contingent upon further testing and design iteration.

“After beginning this journey seven years ago, this first year of testing in the unforgivable environment of the high seas strongly indicates that our vision is attainable and that the beginning of our mission to rid the ocean of plastic garbage, which has accumulated for decades, is within our sights,” said Slat.

“Our team has remained steadfast in its determination to solve immense technical challenges to arrive at this point. Though we still have much more work to do, I am eternally grateful for the team’s commitment and dedication to the mission and look forward to continuing to the next phase of development,” he said.

Rethinking Plastics Recycling

Even the most recyclable plastic, PET – or poly(ethylene terephthalate) – is only recycled at a rate of 20-30 percent, with the rest typically going to incinerators or landfills, where it takes centuries to decompose.

Now a team of researchers at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory has designed a recyclable plastic that, like a Lego playset, can be disassembled into its constituent parts at the molecular level, and then reassembled into a different shape, texture, and color again and again without loss of performance or quality. The new material, called poly (diketoenamine), or PDK, was reported in the journal “Nature Chemistry” in May.

“Most plastics were never made to be recycled,” said lead author Peter Christensen, a postdoctoral researcher at Berkeley Lab’s Molecular Foundry, a DOE facility that specializes in nanoscale science. “But we have discovered a new way to assemble plastics that takes recycling into consideration from a molecular perspective.”

All plastics, from water bottles to automobile parts, are made up of large molecules called polymers, which are composed of repeating units of shorter carbon-containing compounds called monomers.

According to these researchers, the problem with many plastics is that the chemicals added to make them useful – such as fillers that make a plastic tough, or plasticizers that make a plastic flexible – are tightly bound to the monomers and stay in the plastic even after it’s been processed at a recycling plant.

During processing at such plants, plastics with different chemical compositions – hard plastics, stretchy plastics, clear plastics, candy-colored plastics – are mixed together and ground into bits. When that hodgepodge of chopped-up plastics is melted to make a new material, it’s hard to predict which properties it will inherit from the original plastics.

This inheritance of unknown and therefore unpredictable properties has prevented plastic from becoming what many consider the Holy Grail of recycling: a “circular” material whose original monomers can be recovered for reuse for as long as possible, or “upcycled” to make a new, higher quality product.

These researchers believe that their new recyclable plastic could be a good alternative to many nonrecyclable plastics in use today.

“We’re at a critical point where we need to think about the infrastructure needed to modernize recycling facilities for future waste sorting and processing,” said Helms. “If these facilities were designed to recycle or upcycle PDK and related plastics, then we would be able to more effectively divert plastic from landfills and the oceans. This is an exciting time to start thinking about how to design both materials and recycling facilities to enable circular plastics,” said Helms.

The researchers next plan to develop PDK plastics with a wide range of thermal and mechanical properties for applications as diverse as textiles, 3D printing, and foams. In addition, they are looking to expand the formulations by incorporating plant-based materials and other sustainable sources.

Enlisting the Help of Microorganisms

An innovative new study to develop microbial organisms that can digest plastic waste has been made possible following a £1.5 million award from the ERA Cobiotech program of the European Union, which aims to maximize synergies among current mechanisms of biotechnology research funding in Europe.

Researchers from the University of Surrey together with colleagues from Germany, Spain and France are set to start work on a novel technique to tackle plastic waste, potentially revolutionizing recycling.

Engineered microbial communities will be created by the team to digest two types of plastic polymers, polyethylene terephalate (PET) and polyurethane (PU), and transform them into molecules that can be used to develop a more environmentally friendly material, Bio-PU, which is used as a construction and insulation material.

PET is one of the main polymers for single-use plastics such as water bottles and food trays. Current physical or chemical methods to degrade PET are inefficient due to the presence of impurities and are expensive due to energy costs associated with the high temperatures required to break down the material.

This new technique could generate an unconventional way to recycle that could increase recycling rates.

Dr. Jose Jimenez, senior lecturer in synthetic biology at the University of Surrey, said, “Moving away from the reliance on single use plastics is a positive step; however, the problem of how we deal with current plastic waste still needs to be addressed. Our project will investigate the ability of micro-organisms to digest plastic waste, turning it into a more environmentally friendly material that can be recycled.”

From Plastics to Jet Fuel

In June, a research group from Washington State University announced that it has produced jet fuel by melting plastic waste at high temperatures using an activated carbon catalyst.

“Waste plastic is a huge problem worldwide,” said Professor Hanwu Lei. “This is a very good and relatively simple way to recycle these plastics as they contain a lot of hydrogen, which is a key component in fuel.”

In the experiment, Lei and colleagues tested low-density polyethylene as well as water bottles, milk bottles, and plastic bags. The plastic materials were first ground down into three millimeter pieces, about the size of a grain of rice, and then placed on top of activated carbon in a tube reactor at temperatures ranging from 430°C (806°F) to 571°C (1,060°F).

“Plastic is hard to break down,”  Lei said. “You have to add a catalyst to help break the chemical bonds.”

Once the carbon catalyst has done its work, it can be separated out and re-used on the next batch of waste plastic conversion and can also be regenerated after losing its activity. After testing several different catalysts at different temperatures, the best result produced a mixture of 85 percent jet fuel and 15 percent diesel fuel.

“We can recover almost 100 percent of the energy from the plastic we tested,” Lei said. “The fuel is very good quality, and the byproduct gases which are produced are high quality and useful as well.”

Professor Lei says the method for this process is easily scalable. It could work at a large facility or even on farms, where farmers could turn plastic waste into diesel fuel. He said, “This work will hopefully provide an efficient solution to the overwhelming amount of plastic waste produced by our society.”

Maximpact experts have solutions for communities attempting to cope with plastic waste. Please contact info@maximpact.com for more information.