A study published in 2022 asks the question, ‘when do we know enough to stop researching plastic pollution?’. The author concludes, ‘not yet, and not any time soon’.29 There are many areas where more investigation is urgently needed, some of which we have covered already. Now we'll focus on three key areas for further exploration: mapping plastic pollution, plastic waste management and marine ecosystems.
One concern about plastic pollution is that we do not know the true extent of its volume in the ocean. Researchers are able to find what it is on the surface, but it is more challenging to quantify what is at the bottom of the ocean and on beaches.30 Even with surface litter, macroplastic items (over 50cm in size) are difficult to map since they occur less frequently than microplastic pieces.31 In 2014, scientists identified rubbish patches in the world's oceans that contain up to 35,000 tons of plastic, accounting for less than 1 percent of the plastic thought to be in the oceans.32
A better understanding of hot spots for plastic pollution would strengthen policy, cleanup programmes and waste management, for instance. It would also help to strengthen support for the most vulnerable populations, since the health impacts of ocean pollution fall disproportionately on populations in the Global South.33
In recent years, new technologies are being employed to start creating more detailed maps than were previously available. Historically, datasets were either built using conventional methods such as trawls, which are labour-intensive, or less conventional but costly methods such as airplanes.34
Organizations such as The Ocean Cleanup are now using tools powered by artificial intelligence to create detailed maps of plastic densities in remote ocean locations.
One tool, Global Plastic Watch, maps the world’s plastic waste using a combination of satellite imagery and artificial intelligence, and is able to detect plastic waste sites as small as 5 by 5 metres, building an interactive map of plastic pollution in near real time. The data gathered is believed to be a world first.35 These tools are still fairly new, but as they generate more data over time, it is likely they will lay the ground for further research.
Much of plastic production is for consumer goods, and over 40% is used in products that are discarded within one year of purchase – often after a single use.36 Between 1950 and 2015, only about 10 percent of plastic produced was recycled globally, and of this, only 10 percent was recycled more than once through closed loop recycling.37 The remaining 90 percent was either incinerated or disposed of in landfills, dumps, or the environment.
Many initiatives have already been implemented globally to reduce plastic waste – such as taxing single-use plastic bags – but the global community has yet to go far enough to truly address the issue. Bans on single-use plastic are a positive start. For instance, India recently banned selected single-use plastic products with ‘low utility and high littering potential’, such as plastic cutlery, earbuds with plastic sticks, and ice cream sticks.38
However, solutions need to be innovative and thorough in their approach, to avoid creating further issues elsewhere. Simply replacing plastics is not necessarily an optimal solution. For instance, replacing plastic packaging with cardboard to transport food may increase pollution, since this increases overall weight and therefore the number of lorries required.39 Life cycle assessments help to understand the environmental impacts of products in a more holistic manner. However, there is a need for more extensive research on appropriate plastic alternatives, on biodegradable polymers, and on conducting life cycle analyses, since the approach may vary for different product types and industries.
Global climate change is having a damaging impact on animal and plant species. Ocean pollution is contributing to this, with all marine life – from plankton and shellfish to birds, turtles and mammals – facing the grave risk of toxification, behavioural disorder, starvation and suffocation.40 Marine species either ingest plastic litter or get entangled in it. Marine wildlife mistake plastic waste for prey, but they may also accidentally ingest micro and nanoplastics due to their small size.
In fact, scientists estimate that 60 percent of all seabird species have eaten pieces of plastic, and this is expected to rise to 99 percent by 2050.41 As plastic debris enters the digestive systems of marine organisms, contaminants are accumulating in the food web over time. Further research is needed on the effects this is having on human health, and the extent of its contribution to global diseases.42
Coral reefs, a vital ecosystem for life underwater, are also suffering the consequences of plastic pollution. When corals, mangroves and seagrass beds are smothered by plastic waste, they are unable to receive oxygen and light.43 Additionally, corals that come into contact with plastic have an 89 percent chance of contracting diseases, compared with a 4 percent likelihood for corals that do not.44
Historically, coral reef conservation – a subject area which inevitably incorporates plastic contamination and damage – was the subject of higher research outputs and citation volumes than marine plastic pollution.45 In the last decade, research on marine pollution is gaining momentum, outstripping attention on coral reefs, with double the output in 2021. At least in part, this may be due to the introduction of the SDG targets.
