Why does this matter? As many of us head off to the beach for our summer holidays, this study serves as a sobering reminder that ocean plastic pollution is an ever-growing issue. As more tourists flock to coastal areas, the volume of single-use plastics, such as bottles, wrappers and bags, often increases, much of it ending up in the sea. It should also make us more mindful of how we dispose of waste and consider using more reusable items.

Nano plastics, which are less than 1,000 nm across and invisible to the eye, can enter the ocean through multiple channels. For example, sunlight, ocean turbulence and temperature fluctuations cause larger plastic items to degrade into smaller particles, eventually reaching the nanoscale.

Nano plastics and larger microplastics – particles less than 5 mm across – resulting from industrial processes, washing synthetic fibres and tyre abrasion, among others, can also flow in from rivers or descend from the air. With an estimated 14 million mt of plastic leaking into the ocean every year, a figure that continues to rise, critical measures are needed now to address the problem.

The study also identified polyvinyl chloride (PVC) and polystyrene (PS) in the collected samples. However, the researchers’ estimate is likely conservative as they were unable to detect two other major classes of plastics known as polyethylene (PE) and polypropylene (PP), although it is highly probable that these also enter the ocean. The team plans further investigations to understand if these particles were obscured by other molecules in the study. They also want to determine if nano plastics are as prevalent in oceans elsewhere.

Recent research has revealed that micro and nano plastics are ingested by a broad range of aquatic species, from microalgae to predators such as eels, with harmful effects including digestive blockages, immune responses, DNA damage and altered gene expression. The severity of these impacts depends on particle size, chemical composition and degradation. Many plastics also contain endocrine disruptors that interfere with hormonal systems.

Ultimately, these particles enter the human food chain, with regular seafood consumers ingesting thousands every year. While health effects are still being studied, early evidence suggests similar risks in humans, including cellular disruption and exposure to toxic additives. Nano plastics may also act as vectors for pathogens or bacteria, potentially raising the risk of infectious diseases.

Another recent study highlights that micro- and nano plastics are discharged in sea sewage spills. When combined with coastal winds, billions of these particles could lift from the sea and enter the air around coastal towns and cities and be inhaled by residents, posing another potential route for the health risks linked to plastics. The authors have urged the UK government to require water companies to filter out micro- and nano plastics from their wastewater.

Still, removing the vast amount of nano plastics already in the ocean is impossible with current technologies. Instead, the focus must be on prevention. Recycling efforts are key, and the global market for recycled ocean plastics is gaining robust momentum. According to a Custom Market Insights report, it is expected to be worth approximately $1.9 billion this year and could reach $3.5bn by 2034.

Bureo is one such company operating in this space, taking discarded fishing nets and transforming them into 100% recycled raw materials used by household names such as Toyota, Patagonia and Trek. Another player in the area is AION, which recycles ocean plastic into everyday items such as shopping baskets and trays that can be returned for further recycling in a truly circular approach.

Beyond recycling, the world must simply use less plastic. Currently, more than 400 million mt of plastic is produced annually and could triple by 2060.

The next meeting to create the legally binding Plastics Treaty will take place from 5 to 14 August in Geneva, Switzerland. This will attempt to finalise the text after negotiations stalled at the previous round of talks in Busan, South Korea, in late 2024. Nevertheless, at the close of that meeting, 100 countries warned there could be no treaty without a cap on plastic production, a call that was reiterated at the UN Ocean Conference in June. The world will be watching to see if this can finally be achieved in the coming weeks.

Why does this matter? Microplastics, categorised as plastic particles under 5 millimetres in diameter, can endure for hundreds to thousands of years in the environment.

These tiny pollutants have permeated the air we breathe, the food we consume, and the water we drink. It’s estimated that some individuals may ingest an amount of microplastics comparable to the size of a credit card each week.

Controlling microplastic pollution is one of the key challenges of our time, but progress has been slow so far. The extent of microplastic pollution cannot be overstated.

Last year, contestants participating in The Ocean Race found microplastics in every water sample taken along its 32,000 nautical mile course. This includes Nemo Point, the most remote location on Earth at 1,670 miles from the nearest shoreline, where 320 microplastics were found per cubic metre of seawater.

Research is accumulating on the implications of microplastics on both wildlife and human health, yet the overarching scientific consensus on the issue is still forming and remains uncertain.

Giuseppe Paolisso and his team at the University of Campania Luigi Vanvitelli studied the build-up of microplastics in arterial plaques in 257 people undergoing surgery to lower stroke risk. Microplastics were detected in the plaques of 150 patients, with the majority of particles identified as polyethylene or polyvinyl chloride.

The study shows a correlation between microplastics and negative health impacts. However, the causes of the build-up and its prevalence in the general population require further research, particularly considering that 40% of the subjects showed no microplastics despite widespread pollution.

Other recent studies have revealed that microplastics can compromise human white blood cell function, reducing the body’s defence against pathogens, and potentially impacting immune health and tissue integrity.

Additionally, microplastics have been found to harbour bacteria and enter the marine food chain, ultimately affecting the gut biomes of seabirds. This raises concerns about the potential escalation of microplastic ingestion by humans due to bioaccumulation through the food chain.

Global action on rampant plastic pollution has been slow. In 2022, 175 nations signed a legally binding treaty on plastics seeking to combat emissions and pollution associated with the material’s production, use and disposal.

At the next negotiating session, the INC-4 in Ottowa, Canada, a revised draft will be up for discussion, with the treaty expected to be finalised by the end of the year.

While international policy develops at a modest pace, the private sector is exploring innovative solutions to a worsening crisis.  AION, for example, helps customers transform their plastic waste problems into valuable solutions.

AOIN’s team of experts conduct in-depth analysis of customers’ plastic product value chains, offering a roadmap to minimise virgin plastic use, integrate recycled materials, and prevent plastic waste generation.

At the other end of the plastic lifecycle, Bureo transforms discarded fishing nets into valuable recycled raw materials. To date, Bureo has collected and recycled more than 4.5 million kg of nets, operating collection programmes in six countries. Their innovative approach has caught the attention of leading brands including Patagonia, Toyota, and Trek.

Why does this matter? Ocean plastic proliferation is only set to get worse without action, with annual plastic leakage set to treble to reach 29 million tonnes annually by 2040 and the ocean plastic stock set to quadruple by this date – rising to 646 mt. This could help push species towards extinction, with evidence also emerging that ocean microplastic can cause sea creatures to develop abnormally.

To tackle the issue, efforts are being focused on a number of fronts, including on devices to collect plastic already in the oceans. The above highlighted new study, however, describes the projected impact of ocean clean up devices as “very modest”. The forecasted impact remained limited even when the researchers’ model calculated the effect of 200 clean-up devices across the ocean working continuously for 120 years.

The Ocean Cleanup’s Matthias Egger disputes the findings, stating the study underestimates the device and, if it is deployed at areas of high plastic concentration such as the Great Pacific garbage patch, it will be more effective.

Submerged plastic, however, is substantially more difficult to remove than plastic floating at the top of the ocean. Separate reports indicate around 99% of ocean plastic ultimately ends up in the deep sea, with around 35 times more plastic currently in all levels of the ocean than the amount located at its surface.

While clean up devices may play a small role, it’s much more important to stop plastic entering the marine environment in the first place. In a piece arguing ocean clean-up devices are an uneconomic “dangerous distraction”, Systemiq’s Yoni Shiran likens the issue to a flooded house – you should first turn off the tap before you start mopping the floor.

Global rivers and waterways are a significant source of ocean plastic, with analysis indicating up to 34 mt of plastic emissions enter these each year. Collecting this before it reaches the ocean is one solution. Ocean Cleanup is also developing solar powered river-based devices, such as its Interceptor, which can trap and collect plastic before it reaches the sea.

Elsewhere, bubble barriers are being tested to push plastic to waterway surfaces for collection. Mapping the problem can also help – in Japan, researchers have developed a high-resolution plastic emissions map of the country to enable waterway problem areas to be targeted for reduction efforts.

Of course, better still would be to stop plastic even entering waterways, where it still impacts water-based species. Indonesia is embarking on a strategy to reduce the amount of plastic entering its waters by 70% by 2025 through doubling plastic waste collection and recycling, redesigning plastic products and expanding waste disposal facilities. Alongside corporate pledges to reduce virgin plastic use, recycling and circular economic principles and technologies can help, with plastic able to be repurposed into hydrocarbon feedstocks for new plastic, chemical products, low-sulphur oil or even hydrogen.

Sources: Eco-Business

Science of the Total Environment