Plastic Pollution: Causes, Sources, Effects & Solutions

Plastic Pollution: Causes, Sources, Effects & Solutions

Waste pollution is a big issue in the world.

One of the most destructive waste materials is plastic, and plastic pollution can have significant impacts on humans, animals and the natural environment.

In this guide we discuss what plastic pollution is, the causes, the sources of plastic production, the effects, and potential solutions to mitigate and reduce plastic pollution.

(NOTE: we have heavily paraphrased in this guide. You can find their full articles here –, and here

You can also read more generally about waste pollution in this guide


Summary – Plastic Pollution

  • Plastic is often cheap, durable, takes a long time to break down, and can be used for a range of uses in society – making it a popular material that delivers both pros and cons
  • Plastic comes in many different types, forms and sizes
  • Single use plastic can be delineated from plastics that last multiple years or even decades (such as plastics used in construction)
  • Microplastics happen with the break down of bigger plastic items and material
  • In developed countries, plastic may be disposed of via landfills, incineration and recycling. Plastic is generally well contained and handled in countries with good waste management systems (landfills tend to be well managed and contained compared to poorer countries)
  • In developing countries, or countries with poor waste management systems – plastic is often littered, disposed of in unconfined landfills (where it blows or washes away), and can end up in rivers … where it gets carried out to sea
  • Most of the plastic found in the ocean comes from Asia – carried from rivers in China and India for example
  • Countries around the middle of the global income spectrum tend to have the highest per capita mismanaged plastic rates
  • High income countries produce far more plastic per person than low and middle income countries in general – but, once you correct figures for amount of mismanaged plastic waste, they have less impact on plastic pollution that ends up in the environment
  • Industries that produce the most primary plastics are packaging, with 42 percent of plastics entering the use phase. Building and construction was the second largest sector utilizing 19 percent of the total. But, plastic packaging tends to be far more of the single use kind
  • In terms of household waste, EPA figures show plastic trails paper, food and yard trimmings waste. Plastic accounts for around 13% of municipal waste
  • An often overlooked cause of plastic waste is fishing equipment and fishing gear from things such as ghost fishing and commercial fishing waste. Nets and fishing lines are common fishing waste found in the ocean
  • Reducing plastic waste, and mismanaged plastic waste, will involve a collaborative approach between individuals, the government and private business 
  • Aside from reducing plastic waste, we need to find better ways to re-use, recycle and dispose of plastic
  • With effective waste management systems across the world, mismanaged plastics at risk of entering the ocean could decline by more than 80 percent. If we focus all of our energy on contributions of negligible size [like plastic straws which are only 0.03% of total plastic waste in the ocean], we risk diverting our focus away from the large-scale contributions we need.
  • In terms of mismanaged waste (littering and inadequately disposed of), a high share of the world’s ocean plastics pollution has its origin in Asia. China contributes the highest share of mismanaged plastic waste with around 28 percent of the global total, followed by 10 percent in Indonesia, 6 percent for both the Philippines and Vietnam.
  • Other leading countries include Thailand (3.2 percent); Egypt (3 percent); Nigeria (2.7 percent) and South Africa (2 percent).


What Is Plastic Pollution?

Plastic entering the environment and harming humans, animals, living organisms, and the natural environment.

Once plastic is discarded, it can either be adequately disposed of via properly managed landfills, incinerators or recycling.

It can also be mismanaged via littering or inadequately managed disposal sites.


Types Of Plastic

  • Polymers, synthetic fibers and additives
  • Primary plastics and other plastics
  • Nano plastics, small micro plastics, large micro plastics, meso plastics, macro plastics



  • Plastics that act as pollutants are categorized into micro-, meso-, or macro debris, based on size.

– Wikipedia


Stages Of The Plastic Pollution Cycle, & How Plastic Pollution Generally Happens

From 2014 and 2015 estimates:

  • Production – plastic is made (270 million tonnes)
  • Global plastic waste – amount of plastic disposed of (275 million tonnes – can be more than production numbers in any given year because plastic from previous years becomes waste)
  • Coastal plastic waste – total of plastic generated by populations within 50km of a coastline, which is at most risk of entering the ocean (99.5 million tonnes)
  • Mismanaged coastal plastic waste – sum of inadequately managed and littered waste from coastal populations. Inadequately managed waste is stored in open or insecure landfills. (31.9 million tonnes)
  • Plastic inputs to the ocean – micro and macro plastic waste input into the ocean (8 million tonnes)
  • Estimated plastic in surface water – 10,000 to 100,000 tonnes. Can end up in animals and on ocean floor



How Is Plastic Generally Disposed Of?

Of the plastic produced, some of it stays in use for various applications, but the plastic that that doesn’t stay in use (like single use plastics for example), needs to be disposed of.

This is done mainly via landfills, incineration and recycling.

In 2015, an estimated 55 percent of global plastic waste was discarded, 25 percent was incinerated, and 20 percent recycled.

If we extrapolate historical trends through to 2050 —  by 2050, incineration rates would increase to 50 percent; recycling to 44 percent; and discarded waste would fall to 6 percent. However, note that this is based on the simplistic extrapolation of historic trends and does not represent concrete projections.



When Did Plastic Pollution Start Becoming A Problem?

  • Rapid growth in global plastic production started in the 1950’s
  • From 1950 to 2015, annual production of plastics increased nearly 200-fold to 381 million tonnes in 2015



Biggest Reasons For Plastic Pollution

  • Plastic is inexpensive, easy and cheap to make
  • Plastic is durable as a material
  • Plastic has a lot of benefits (such as preventing food waste, and packaging)
  • The chemical structure of most plastics renders them resistant to many natural processes of degradation and as a result they are slow to degrade – they stick in the natural environment around and cause damage in the environment
  • Macro plastics break down – but break down into micro plastics



Causes, & Sources Of Plastic Pollution

Land Based vs Marine Based Plastics

  • Approximately 70-80 percent of ocean plastics come from land-based sources, and 20-30 percent from marine.
  • Whilst this is the relative contribution as an aggregate of global ocean plastics, the relative contribution of different sources will vary depending on geographical location and context.
  • In particular regions, marine sources can dominate.
  • For example, more than half of plastics in the Great Pacific Garbage Patch (GPGP) come from fishing nets, ropes and lines. It’s estimated that plastic lines, ropes and fishing nets comprise 52 percent of the plastic mass in the ‘Great Pacific Garbage Patch’ (GPGP) (and comprises 46 percent of the megaplastics component of the GPGP). The relative contribution of marine sources here is likely to be the result of intensified fishing activity in the Pacific Ocean.

Industries & Sectors That Use Plastic The Most

  • Packaging was the dominant use of primary plastics, with 42 percent of plastics entering the use phase. Building and construction was the second largest sector utilizing 19 percent of the total.
  • Primary plastic production does not directly reflect plastic waste generation, since this is also influenced by the polymer type and lifetime of the end product.
  • Packaging, for example, has a very short ‘in-use’ lifetime (typically around 6 months or less). This is in contrast to building and construction, where plastic use has a mean lifetime of 35 years. Packaging is therefore the dominant generator of plastic waste, responsible for almost half of the global total.
  • Since packaging tends to have a much lower product lifetime than other products (such as construction or textiles), it is also dominant in terms of annual waste generation. It is responsible for almost half of global plastic waste
  • In 2015, primary plastics production was 407 million tonnes; around three-quarters (302 million tonnes) ended up as waste.
  • Are straws a big deal? Not really. It’s estimated that if all straws around the world’s coastlines were lost to the ocean, this would account for approximately 0.03 percent of ocean plastics. A global ban on their use could therefore achieve a maximum of a 0.03 percent reduction. Why have straws in particular received so much attention? Probably because: (a) for most people (not all — some people struggle to drink without one), straws are unnecessary; and (b) it’s a quick and low-risk step for businesses to be seen to be taking active steps in addressing this issue.
  • As some have highlighted: other sources of plastic pollution — such as discards of fishing nets and lines (which contributed to more than half of plastics in the Great Pacific Garbage Patch) receive significantly less attention. With effective waste management systems across the world, mismanaged plastics at risk of entering the ocean could decline by more than 80 percent. If we focus all of our energy on contributions of negligible size, we risk diverting our focus away from the large-scale contributions we need.



Countries That Contribute To Plastic Waste & Pollution

  • High-income countries tend to generate more plastic waste per person
  • How plastic waste is managed determines its risk of entering the ocean. High-income countries have very effective waste management systems; so, mismanaged waste (and ocean inputs) are therefore low. Poor waste management across many middle- and low-income countries means they dominate the sources of global ocean plastic pollution
  • Daily per capita plastic waste across the highest countries – Kuwait, Guyana, Germany, Netherlands, Ireland, the United States – is more than ten times higher than across many countries such as India, Tanzania, Mozambique and Bangladesh. Note that these figures represent total plastic waste generation and do not account for differences in waste management, recycling or incineration. They therefore do not represent quantities of plastic at risk of loss to the ocean or other waterways.
  • Mismanaged, inadequately disposed and littered plastic is a problem, compared to say contained and managed plastic in landfills or incinerated plastic
  • In terms of mismanaged waste (littering and inadequately disposed of), a high share of the world’s ocean plastics pollution has its origin in Asia. China contributes the highest share of mismanaged plastic waste with around 28 percent of the global total, followed by 10 percent in Indonesia, 6 percent for both the Philippines and Vietnam.
  • Other leading countries include Thailand (3.2 percent); Egypt (3 percent); Nigeria (2.7 percent) and South Africa (2 percent).
  • Whilst many countries across Europe and North America had high rates of per capita plastic generation, once corrected for waste management, their contribution to mismanaged waste at risk of ocean pollution is significantly lower.
  • The East Asia and Pacific region dominates global mismanaged plastic waste, accounting for 60 percent of the world total.
  • Plastic enters the ocean from many different sources, and rivers contribute greatly. The Yangtze, Ganges and Xi are the main offenders, with China and India being home to most of the plastic polluted rivers
  • Asia contributed to 86% of river plastic pollution in 2015



Plastic In The Ocean

  • It’s estimated that around three percent of global annual plastic waste enters the oceans each year. In 2010, this was approximately 8 million tonnes.
  • Plastic enters the oceans from coastlines, rivers, tides, and marine sources
  • Most of the plastic that enters the ocean is from coastline populations that are located 50km or less from the ocean itself
  • The distribution and accumulation of ocean plastics is strongly influenced by oceanic surface currents and wind patterns.
  • Eriksen et al. (2014) estimated that there was approximately 269,000 tonnes of plastic in ocean surface waters across the world.
  • It’s estimated that there are more than 5 trillion plastic particles in the world’s ocean surface waters
  • The majority of plastics by mass are large particles (macroplastics), whereas the majority in terms of particle count are microplastics (small particles).
  • Great Pacific Garbage Patch – the estimated composition of the GPGP plastic…. Around 52 percent of plastics originated from fishing activity and included fishing lines, nets and ropes; a further 47 percent was sourced from hard plastics, sheets and films; and the remaining components were small in comparison (just under one percent). The dominance of fishing lines, nets, hard plastics and films means that most of the mass in the GPGP had a large particle size (meso- and macroplastics).
  • To understand where plastic entering the oceans is coming from, we are primarily concerned with mismanaged waste in coastal populations. Mismanaged waste is plastics which are disposed of in open landfills or dumps, littered, or otherwise discarded by means which can spill out to the surrounding environment.
  • River inputs are a significant source of plastic inputs to the ocean.



The Missing Plastics Problem In The Ocean

  • When you look at the amount of plastic that enters oceans and the amount of plastic that floats on ocean surfaces, the amounts don’t add up
  • This is known as the missing plastics problem i.e. figuring out where the plastic is going once it enters the ocean
  • It’s unknown where the majority of ocean plastics end up as plastic is hard to track once it enters the ocean. There are multiple hypotheses as to where missing plastic accumulates.
  • It’s important to note that within the marine environment, plastics can more readily break down into smaller particles: exposure to ultraviolet (UV) radiation, and consistent mechanical abrasion from wave action can cause larger particles to break down. This allows for easier incorporation into sediments and ingestion by organisms.
  • A likely ‘sink’ for ocean plastics are deep-see sediments; a study which sampled deep-sea sediments across several basins found that microplastics, in the form of fibres, was up to four orders of magnitude more abundant (per unit volume) in deep-sea sediments from the Atlantic Ocean, Mediterranean Sea and Indian Ocean than in plastic-polluted surface waters.
  • The other possible ‘sinks’ of missing plastics are shallow-sea sediments, in addition to potential ingestion by organisms.
  • The quantification of these aspects are as yet unknown.



Effects & Impact Of Plastic Pollution

  • Plastic has a large negative impact on wildlife and oceans
  • For wild animals, entanglement with plastic and ingestion of plastic are big issues
  • Abrasion with plastic is also an issue – for example fishing gear damaging coral
  • With micro plastics, the key concern is ingestion for animals. This can occur through several mechanisms, ranging from uptake by filter-feeders, swallowing from surrounding water, or consumption of organisms that have previously ingested microplastics.
  • Ingestion of plastic can occur unintentionally, intentionally, or indirectly through the ingestion of prey species containing plastic and it has now been documented for at least 233 marine species, including all marine turtle species, more than one-third of seal species, 59% of whale species, and 59% of seabirds. Ingestion by 92 species of fish and 6 species of invertebrates has also been recorded.
  • Microplastic ingestion rarely causes mortality/death in any organisms
  • There is increasing evidence that microplastic ingestion can affect the consumption of prey, leading to energy depletion, inhibited growth and fertility impacts. When organisms ingest microplastics, it can take up space in the gut and digestive system, leading to reductions in feeding signals. This feeling of fullness can reduce dietary intake.
  • Many organisms do not exhibit changes in feeding after microplastic ingestion. A number of organisms, including suspension-feeders (for example, oyster larvae, urchin larvae, European flat oysters, Pacific oysters) and detritivorous (for example, isopods, amphipods) invertebrates show no impact of microplastics.
  • Overall, however, it’s likely that for some organisms, the presence of microplastic particles in the gut (where food should be) can have negative biological impacts.
  • Entanglement cases have been reported for at least 344 species to date, including all marine turtle species, more than two-thirds of seal species, one-third of whale species, and one-quarter of seabirds. Entanglement by 89 species of fish and 92 species of invertebrates has also been recorded.
  • Entanglements most commonly involve plastic rope and netting and abandoned fishing gear. However, entanglement by other plastics such as packaging have also been recorded.
  • There is, currently, very little evidence of the impact of microplastics in humans. Despite having no clear evidence of health impacts, research on potential exposure is ongoing.
  • For human health, it is the smallest particles — micro- and nano-particles which are of greatest concern. Particles must be small enough to be ingested.
  • There are several ways by which plastic particles can be ingested: orally through water, consumption of marine products which contain microplastics, through the skin via cosmetics (identified as highly unlikely but possible), or inhalation of particles in the air.
  • One factor which possibly limits the dietary uptake for humans is that microplastics in fish tend to be present in the gut and digestive tract — parts of the fish not typically eaten. The presence of microplastics in fish beyond the gastrointestinal tract (e.g. in tissue) remains to be studied in detail. Micro- and nanoplastics in bivalves (mussels and oysters) cultured for human consumption have also been identified.
  • However, any human exposure and potential risk is not yet able to be identified or quantified.
  • Plastic fibres have also been detected in other food items; for example, honey, beer and table salt. However, it’s expected there is negligible health risks as a result of this exposure.
  • Levels of microplastic ingestion are currently unknown. Even less is known about how such particles interact in the body. It may be the case that microplastics simply pass straight through the gastrointestinal tract without impact or interaction.
  • What could cause concern about the impact of microplastics?
  • Three possible toxic effects of plastic particle have been suggested: plastic particles themselves, the release of persistent organic pollutant adsorbed to the plastics, and leaching of plastic additives. There has been no evidence of harmful effects to date (however, the precautionary principle would indicate that this is not evidence against taking exposure seriously).
  • To date, there has been no clear evidence of the accumulation of persistent organic pollutants or leached plastic additives in humans. Continued research in this area, however, is important to better understand the role of plastic within broader ecosystems and risk to human health.



You can also read about more negative effects of plastic pollution in the disposal sections below – landfill, incineration and recycling.


Trends And Stats On Plastic Production

  • From 1950 to 2015, annual production of plastics increased nearly 200-fold to 381 million tonnes in 2015
  • In 1950 the world produced only 2 million tonnes per year
  • In 2010 – global primary production of plastic was 270 million tonnes
  • In 2010 – global plastic waste was 275 million tonnes (and can exceed annual primary production through wastage of plastic from prior years)
  • In 2010 – plastic waste most at risk of entering the oceans is generated in coastal populations (within 50 kilometres of the coastline); coastal plastic waste amounted to 99.5 million tonnes in 2010
  • In 2010 – only plastic waste which is improperly managed (mismanaged) is at significant risk of leakage to the environment; in 2010 this amounted to 31.9 million tonnes. Of this, 8 million tonnes – 3% of global annual plastics waste – entered the ocean (through multiple outlets, including rivers)
  • In 2010 – an estimated 10,000s to 100,000s tonnes of plastics are in the ocean surface waters (several orders of magnitude lower than ocean plastic inputs). This discrepancy is known as the ‘missing plastic problem’ and is discussed here in this guide
  • Cumulatively – by 2015, the world had produced 7.8 billion tonnes of plastic — more than one tonne of plastic for every person alive today.
  • In 2015, an estimated 55 percent of global plastic waste was discarded, 25 percent was incinerated, and 20 percent recycled.
  • Between 1950 to 2015 – cumulative production of polymers, synthetic fibers and additives was 8300 million tonnes. Very little has been re-used or recycled
  • Plastic waste generation tends to increase as we get richer. Per capita plastic waste at low incomes tends to be notably smaller.
  • Mismanaged waste generation tends to be low at very low incomes (since per capita waste is small); it then rises towards middle incomes; and then falls again at higher incomes. Countries around the middle of the global income spectrum therefore tend to have the highest per capita mismanaged plastic rates.
  • This has typically occurred where countries have rapidly industrialised (allowing for significant economic growth towards the middle of the income spectrum), but at a rate far exceeding progress in waste management. Waste management infrastructure has failed to keep pace with industrial and manufacturing growth, leading to higher rates of mismanaged waste.
  • It is also the case that countries with high levels of mismanaged waste also have large coastal populations (as shown in the second chart below). This exacerbates the challenge of ocean plastic pollution because poorly-managed waste is at high risk of entering the ocean.
  • Overall, it’s generally the case that plastic waste per person is highest in high-income countries. However, richer countries tend to have effective waste management systems meaning mismanaged waste is low. Most mismanaged waste tends to arise from low-to-middle income countries where large coastal populations and rapid industrialization means waste management systems have failed to keep pace.
  • Oil used to make plastic – Estimates vary by source, but tend to converge on a range between 4 to 8 percent of global oil consumption. 6 percent of global oil consumption is taken as the mid-range estimate.



Forecasts For Mismanaged Plastic (Inadequately Disposed, & Littered Plastic)

  • Overall we see that the global distribution is projected to change only slightly; whilst China’s contribution falls by a couple of percentage points, East Asia & Pacific maintain around 60 percent of the total. South Asia’s contribution — largely driven by India — increases slightly, as does Sub-Saharan Africa. Latin America, the Middle East & North Africa, Europe and North America all fall in relative terms.



Solutions For Plastic Pollution

  • Plastic substitutes and alternatives – it’s also important to note that plastic is a unique material with many benefits: it’s cheap, versatile, lightweight, and resistant. This makes it a valuable material for many functions. It can also provide environmental benefits through certain supply chains: it plays a critical role in maintaining food quality, safety and preventing waste. The trade-offs between plastics and substitutes (or complete bans are therefore complex and could create negative knock-on environmental impacts
  • Fix high and low income country waste management systems so there is less waste that escapes
  • The development of effective waste management infrastructure, particularly in middle-income (and growing lower-income) countries will be crucial to tackling the issue of mismanaged plastic pollution.
  • As some have highlighted: other sources of plastic pollution — such as discards of fishing nets and lines (which contributed to more than half of plastics in the Great Pacific Garbage Patch) receive significantly less attention. With effective waste management systems across the world, mismanaged plastics at risk of entering the ocean could decline by more than 80 percent. If we focus all of our energy on contributions of negligible size, we risk diverting our focus away from the large-scale contributions we need.



According to, further things we can do to stop plastic entering the ocean as individuals, innovators, corporations, and in policy-making and financing are…


  • Cut out non-essential plastics where possible, as long as we are not taking away from benefits the plastic might be providing
  • If you can replace single-use plastics with long-term, sustainable alternatives then substitute. To make this worthwhile across other environmental metrics (e.g. energy use, water use, greenhouse gas emissions), you often need to use them many times over a significant period of time. If you continually purchase alternatives to single-use plastic bags, for example, you’re probably increasing your environmental impact in other ways.
  • In most cases, recycling plastic is better than incineration or landfill. Therefore recycle whenever possible.
  • Note though that most plastics are recycled only once or a few times before also ending up in landfill or incineration. The notion that recycled plastic has no impact (and can therefore be used indefinitely) is a misconception.
  • Look at your local recycling guidelines to make sure you know what can and can’t be recycled in your area. Avoid putting plastics in recycling which cannot be handled properly. If in doubt, you’re better to put it in landfill than risk contaminating the whole recycling load (if recycling loads have significant levels of contamination they be judged to be non-economic to sort and therefore sent straight to landfill).
  • In high-income countries (typically with good waste management systems), plastics at risk of entering the ocean arise from littering and dumping of waste by the public.
  • Don’t litter or abandon your waste, and call out anyone who does. Through collective action, zero tolerance can become a societal norm.
  • As individuals we can be limited in the magnitude of our impact. The above changes can make a contribution, but as the late David MacKay noted: “If we all do a little, we’ll only achieve a little”.
  • Even if all countries across Europe and North America cut out plastic use completely, global mismanaged plastic would decline by less than five percent. To drive urgent and large-scale change, arguably our most important role lies in putting pressure on governments and policy-makers to collaborate globally.

Governments and policy-makers:

  • It has been a historic trend that some high-income countries have exported some of their recyclable plastics elsewhere. This has often been to mid- and low-income countries where poor waste management infrastructure has led to high levels of mismanaged waste. This exported waste is therefore at risk of entering the ocean.
  • High-income countries should manage all of their waste appropriately and avoid such transfers to countries which higher risk of poor management.
  • Some have proposed that if trade of recycled plastics was maintained, mid- or low-income countries should tax the plastics they accept. These taxes should be used to expand and improve waste management infrastructure.
  • An estimated 20 percent of ocean plastic pollution results from the fishing industry. However, in particular regions — for example, the Great Pacific Garbage Patch — fishing activity is estimated to generate more than half of plastic pollution. Implementing and monitoring of strict regulations on the prevention of waste from fishing activity is important not only at national levels but through regional and global cooperation.
  • The majority of plastic enters the ocean as a result of inadequate waste management; open landfills and dumps can’t effectively prevent plastics from being lost to the environment. Improving waste management infrastructure – particularly across industrializing countries – is critical and urgent if we are to prevent and reduce plastics entering the ocean.
  • As a general sense of magnitude: if all countries had the management infrastructure of high-income countries (i.e. no mismanaged waste with the exception of littering), global plastics at risk of entering the ocean could decline by more than 80 percent.
  • Global cooperation to upscale waste management is therefore crucial. Such solutions are not new or innovative: they have already been implemented successfully across many countries. Note that this is not a case of finger-pointing or blame: rich countries too have benefited from the rapid industrialization (a rate at which waste management could not keep up) of others. This is a global system we have collective responsibility for.
  • Middle- and low-income countries where plastics are poorly managed have an obvious role and responsibility. But if high-income countries are truly serious about addressing the ocean plastic issue, the most impactful way to contribute is to invest in the improvement of waste management infrastructure practices across the world. Without such investment and cooperation we will not be able to reduce the quantity of plastic entering the ocean.
  • We are still currently on a trend of rapidly increasing plastic waste: to stabilise, let alone reduce, will require large-impact solutions.

Innovation and industry:

  • Effective management of waste we produce is an essential and urgent demand if we are to prevent plastic entering the ocean. This is a solution we know how to achieve: many countries have low levels of mismanaged waste. This is important, regardless of how successful we are in reducing plastic usage.
  • However, reducing demand for new plastic production is also crucially important. Whilst recycled plastic is usually favourable to primary plastics, it is not a long-term solution: most recycled plastics still end up in landfill or incineration after one or two cycles.
  • For recycling to be sustainable over the long-term, innovations which would allow for continuous recycling would have to be developed. There has been promising progress in recent years in the development of polymer materials which can be chemically recycled back to their initial raw materials. However, they are currently expensive and unfavourable in terms of energy inputs.
  • The economic viability and environmental trade-offs will be critical components to the development of not only recyclable materials but other alternatives. Plastic is so widely used because it is cheap, versatile, and requires relatively little energy, water and land to produce.
  • To achieve wide uptake of alternatives across countries of all income levels, breakthrough alternatives will have to be economically competitive with current methods. Functionality, price and scalability of innovations are key to addressing this challenge.


According to, this information on removing plastics already in the ocean:

  • Plastic removal at large-scale is always going to be a major challenge.
  • This becomes an even greater challenge over time, since plastics in the ocean tend to break down into smaller particles (and the smaller they are, they less easy it is to detect and them remove them at scale).
  • Of course the easiest way to mitigate this problem is to stop plastic entering the ocean in the first place.
  • But still, we already have a large quantity of plastic in the ocean and this will continue (even if we can begin to reduce the amount that reaches the ocean in the years which follow).
  • Very small particles (microplastics, for example) are difficult to remove.
  • Technologies being proposed currently for plastic removal therefore tend to focus on larger plastics.
  • The fact that plastic tends to accumulate in gyres at the centre of ocean basins makes this easier: it concentrates plastics for removal.
  • The removal solution which has received the most attention from investors and researchers is The Ocean Cleanup. They are focusing on one major gyre of plastic: the Great Pacific Garbage Patch. Their technology in simple terms deploys buoyant tubes several kilometres in length. The project claim it can capture plastic ranging in size from tens of metres down to 1 cm.
  • It’s too early to say whether this could be a feasible contribution. You can follow their milestone journey here. They make some bold claims, stating that full deployment of the technology could remove 50% of the plastic within 5 years. The prototype has been proven at various small-scales and in the summer of 2018 launch their first cleanup system in the Great Pacific Garbage Patch. If all goes well, their timeline suggests they aim to expand globally in 2020.


According to, this is information on worms that can eat plastic:

  • In 2017 researchers discovered that the wax worm (the larvae of the wax moth) has the ability to break down polyethylene (PE).
  • PE accounts for around 40% of global plastics.
  • PE is largely non-degradable, but there have been a couple of previous instances where particular bacteria or fungi have been able to break it down at very, very slow rates.
  • This latest discovery of the wax worm, however, showed faster rates of breakdown — although still slow.
  • The researchers left 100 wax worms on a PE plastic bag for 12 hours and measured a 92 milligram breakdown of the plastic (about 3% of the plastic bag).
  • These rates are of course very slow, and at a tiny scale.
  • The plan wouldn’t be to scale-up the use of wax worms for plastic degradation — this would be unscalable.
  • However, this discovery could be useful in allowing us to identify a particular enzyme which breaks down plastics.
  • The authors suggest that wax worms break down the carbon-carbon bonds in PE either from the organism itself, or from the generation of a particular enzyme from its flora.
  • It could be possible to produce this enzyme or the bacteria which secrete this given enzyme at industrial scales.


According to, this is information on bacteria that can break down plastic:

  • There are particular strains of bacteria that are effective in breaking down plastic.
  • The most prominent discovery of this bacteria was made in Japan where researchers found a bacterium, Ideonella sakaiensis 201-F6, which could digest polyethylene terephthalate (PET) — the material used for single-use plastic bottles.
  • This bacterium does so by producing and secreting an enzyme called PETase.
  • PETase (a protein which accelerates reactions) can split certain chemical bonds in PET; the bacteria can then absorb the smaller molecules it left behind (which contain carbon, and can be used by the bacteria as fuel/food).
  • This breakthrough has been shown at very small laboratory scales.
  • However, the authors and researchers in this field are open about the fact that this is not a near-term solution and would take major technological and scientific developments before it can close to the scale that would have an impact.


Plastic Pollutes & Damages, But Is Also Beneficial In Several Ways – So, It’s Hard To Completely Ban It

  • It’s also important to note that plastic is a unique material with many benefits: it’s cheap, versatile, lightweight, and resistant. This makes it a valuable material for many functions. It can also provide environmental benefits through certain supply chains: it plays a critical role in maintaining food quality, safety and preventing waste. The trade-offs between plastics and substitutes (or complete bans are therefore complex and could create negative knock-on environmental impacts
  • Plastic can play a crucial role in many aspects: it is essential to preserving food quality, safety and shelf-life thereby preventing food wastage
  • Plastic plays across many aspects of society. It is a unique material: often lightweight, resilient, usually non-reactive, waterproof and cheap. One example where plastic plays an important role is food packaging. Whilst over-packaging can undoubtedly be a significant issue, packaging of food products is essential for the prevention of food losses, wastage and contamination. Storage and packaging plays a crucial role from harvest all the way through to final consumption of the foods we eat. Even if some consider the final phase of packaging (from retail to home) to be unnecessary, it is likely it has played an important role in preserving food from the farm to the retail stage. It protects foods from pest and disease, significantly increases shelf life, and maintains food safety.
  • Lack of packaging is a major contributor to lack of food security in low to medium income countries
  • In fact, studies have shown that when we compare environmental impacts such as greenhouse gas emissions, energy, water and resource use, plastic packaging tends to have a net positive impact. The impact of plastic production and handling is lower than the impacts which would result from food waste without packaging. Reducing packaging where it is used in excess is useful, however, abandoning packaging completely would have serious implications for food security, safety, and would ultimately lead to large increases in the environment impact of food.
  • The question is therefore: is plastic the best material to use for packaging? Which material is ‘best’ for the environment? As designer and sustainability innovator, Leyla Acaroglu, discusses in her TED Talk ‘Paper beats plastic? How to rethink environmental folklore’, there is no universal consensus on ‘best’ or ‘worst’ materials. Materials have different relative impacts across different environmental metrics. This ultimately leads to trade-offs. Some materials may release fewer greenhouse gas emissions but require more water or fertiliser inputs, for example.
  • There’s no simple answer; your choice would be different depending on the environmental impacts you’re most concerned about. In general, plastic tends to be cheap and has significantly lower greenhouse gas emissions, energy, water and fertilizer inputs than alternatives such as paper, aluminium, cotton or glass.
  • The obvious environmental detriment is it’s pollution of the natural environment when poorly managed. In the charts below we summarise one life-cycle analysis (LCA) study of environmental impacts by grocery bag type. This is based on results from the Danish Environmental Protection Agency.
  • These figures present the number of times a grocery bag would have to be reused to have as low an environmental impact as a standard LDPE (Low-density polyethylene) single-use plastic bag. For example, a value of 5 indicates a bag would have to be reused 5 times to equal the environmental impact of a standard single-use plastic bag.
  • Comparisons of alternatives to plastics and plastic bags can be found here –
  • This presents a complex decision: plastic tends to have lower environmental impact for most metrics with the exception of its non-degradability and marine pollution.



Plastic Trade – Importing & Exporting Of Plastic Between Countries

  • Plastic trade – the importing and exporting of plastic – has been significant in the past
  • China used to import and take in a lot of plastic from other countries, but has stated they are reducing and declining imports now

By 2030, it’s estimated that around 110 million tonnes of plastic will be displaced as a result of the China plastic ban. This plastic waste will have to be handled domestically or exported to another country. Brooks et al. (2018) suggest this ban has several implications:

  • exporting countries can use this as an opportunity to improve domestic recycled infrastructure and generate internal markets;
  • if recycling infrastructure is lacking, this provides further incentive for countries to reduce primary plastic production (and create more circular material models) to reduce the quantity of waste which needs to be handled;
  • it fundamentally changes the nature of global plastic trade, representing an opportunity to share and promote best practices of waste management, and harmonize technical standards on waste protocols;
  • some other countries may attempt to become a key plastic importer in place of China; one challenge is that many countries do not yet have sufficient waste management infrastructure to handle recycled waste imports;
  • countries considering importing significant quantities of plastic waste could consider an import tax specifically aimed at funding the development of sufficient infrastructure to handle such waste.

But there are 3 scenarios – 50%, 75% and 100% ban


Plastics can be challenging to recycle, particularly if they contain additives and a range of different plastic blends. The implications of this complexity are two-fold: in many cases it is convenient for countries to export their recycled plastic waste (meaning they don’t have to handle it domestically); and for importing countries, this plastic is often discarded if it doesn’t meet the sufficient requirements for recycled or is contaminated by non-recyclable plastic. As such, traded plastic waste could eventually enter the ocean through poor waste management systems.



Plastic & Landfill Disposal

  • Landfill is the dumping of plastic in landfill lots/areas
  • It’s important to distinguish between the quality/effectiveness of landfills.
  • The modern definition of a landfill is of a disposal site for materials through burial.
  • This is typically the case in high-income countries today where landfills are well-managed and effectively regulated.
  • However, across many countries today landfill resources can be poorly-managed; in many cases dumped in open landfills, pits or dumps.
  • Such uncontrolled disposal facilities can make plastics vulnerable to pollution of the surrounding environment and at risk of entering the ocean.
  • Well-managed landfill facilities have expectations to gather, compact and safely store waste. In many cases this involves covering or burying with soils or other materials.


However, such landfills still have negative environmental impacts:

Greenhouse gases: when organic matter decomposes to produce methane (CH4) and carbon dioxide (CO2) — both are greenhouse gases which contribute to climate change. In some landfill sites, methane gas can be captured and ‘flared’ (burned) for energy production. Plastic, which is hard to break down, degrades over very long timescales (particularly under low oxygen conditions) does not contribute to this effect.

Leachate: decomposing material can produce nutrient-rich or polluted waters which — if not properly contained — can leach to the surrounding environment and potentially enter waterways and soils. Well-managed landfills are usually surrounded by protective lining to prevent water leaching to the surrounding environment. However, local pollution can occur where this is not implemented effectively, or the lining breaks down and is not replaced.

Where plastics are not handled correctly, some types of plastic — such as polyvinyl chloride; PVC — can leach chemicals such as additives and plasticiser compounds. A report by the European Commission aimed to provide a detailed analysis and overview of the available evidence on the behaviour of PVC in landfills. The study concluded that whilst leachate of substances as either non-detectable or in very low concentrations, a precautionary approach would deem this material only controllable if landfills are equipped with adequate liner and leachate treatment.



Plastic and Incineration Disposal

  • Incineration is the burning of plastic
  • This is done at very high temperatures


What are the environmental impacts of incineration?

Greenhouse gases: the incineration of plastic produces carbon dioxide (CO2) — a primary driver of global climate change. However, the incineration process can be integrated as a ‘Waste to Energy’ (WtE) solution. WtE is a form of energy recovery; in this case energy from the plastics can be stored and utilised for energy. On a net balance, does incineration therefore have a net positive or negative impact on greenhouse gas emissions?

It depends. The relative gains from energy recovery vary depending on the efficiency of the incineration process in addition to the mix of energy sources it’s replacing. In countries where the energy mix is dominated by fossil fuels, incineration energy recovery can reduce emissions. However, across many countries — most across Europe — where incineration efficiency is low and the energy mix is lower-carbon, this does provide a net source of greenhouse gas emissions.

Air pollution: a common concern of incineration is that it releases toxic emissions to the surrounding environment. The burning of plastics can produce several toxic gases: incomplete combustion of Polyethylene (PE), Polypropylene (PP) and Polystyrene (PS) can release carbon monoxide (CO) and noxious emissions, while polyvinyl chloride (PVC) can produce dioxins.

Such gases can be toxic and dangerous to both human and ecosystem health. Open or uncontrolled burning of plastics should therefore be strongly avoided.

Is this also the case in incinerator facilities? It largely depends on the efficiency and environmental control of emissions of the particular incinerator site. In high-income countries in particular, waste management and incinerator sites are heavily regulated with monitoring of emissions and potential leaks to the surrounding environment.

Modern incinerators have largely dealt with the problem of dioxin or other toxin emissions.

Technologies here include efficient combustion, end-of-pipe treatment, selective catalytic reduction, and the addition of suitable inhibitors.

A study in Belgium, for example, reported no difference in dioxin-serum levels of maintenance workers of municipal waste incinerator facilities — individuals who would experience high exposure rates if such methods were not implemented.

However, such incinerator technologies and standards are not implemented everywhere — in countries where environmental regulation is less strict, unsafe or open burning of municipal waste remains common.

This typically occurs in low-t0-middle income countries.

Studies in India, Kenya and Thailand, for example, report notable pollution from the burning of waste (including the generation of dioxins).

For incineration to become a universally safe solution, standards and uptake of appropriate technologies and approaches must be adopted globally.


Recycling, Landfill or Incineration for Plastics Disposal?

  • With these being the three main options for plastic disposal – it makes sense to know the benefits and drawbacks of each
  • Each has it’s own environmental, health or economic issues, and depending on who you ask and where their agenda lies – each disposal method can be appealing or non appealing
  • Impact of different methods can be assessed across multiple factors including greenhouse gas emissions, energy use, local pollution, and cost of processing.
  • In terms of relative global warming potential (GWP) and total energy use (TEU) of the three methods, Recycling had the lowest global warming potential and energy use across nearly all of the studies
ReferenceMaterial/applicationGlobal warming potential (GWP)
Total energy use (TEU)
Arena et al. 2003PE and PET liquid containersR-L-IR-I-L
Beigl and Salhofer 2004Plastic packagingR-I
Chilton et al. 2010PETR-I
Craighill and Powell 1996PET, HDPE and PVCR-L
Dodbiba et al. 2008Plastics (PE, PS and PVC)R-I
Eriksson and Finnveden 2009Non-recyclable plasticI-L
Eriksson et al. 2005PE
PE, PP, PS, and PET
Finnveden et al. 2005PVC
Foolmaun and Ramjeeawon 2013PETR-L-IR-I-L
Grant et al. 2001PET, HDPE AND PVCR-LR-L
Moberg et al. 2005PETR-I-LR-I-L
Mølgaard 1995Plastics

Perigini et al. 2004PE and PET liquid containersR-L-IR-I-L
Perigini et al. 2005PE and PET liquid containersR-L-IR-I-L
Rajendran et al. 2013PlasticsR-I
Wenisch et al. 2004PlasticsR=L
Wollny et al. 2001Plastic packagingR-L-IR-I-L
M. Al-Maaded et al. 2012Plastics, non-specified

Shonfield 2008PlasticsI-L-R

– Credit:


From an environmental perspective, recycling is usually the best option. This typically holds true, but note that there are a few caveats:

  • this is based on the assumption that recycled material is a one-for-one displacement of primary plastic production, i.e. each tonne of recycled material prevents one tonne of primary material being produced.
  • However, this is not always the case. Recycling processes can often lead to products of lower quality and economic value — often termed ‘downcycling’. This means that we cannot take for granted that this substitution for primary production is one-to-one.
  • Much of the plastic we recycle can only be recycled once or twice. Then it will end up in landfill or incinerated. This means that whilst recycling is the best of the three management options, it’s not a silver bullet.
  • Recycling only delays — rather than prevents — disposal in landfill or incineration.
  • Whilst recycling has clear environmental benefits, it’s not always the most economically-favourable choice.
  • The relative profitability between recycling and the production of new plastic is strongly determined by oil prices. When oil prices are low, it can be cheaper to make raw plastics than to recycle. For example, when crude oil prices were low in 2015-16, the recycling industry struggled to compete with raw material production.
  • Nonetheless, recycling in general is the best of the three options.


Plastics can be challenging to recycle, particularly if they contain additives and a range of different plastic blends.

The implications of this complexity are two-fold: in many cases it is convenient for countries to export their recycled plastic waste (meaning they don’t have to handle it domestically); and for importing countries, this plastic is often discarded if it doesn’t meet the sufficient requirements for recycled or is contaminated by non-recyclable plastic.

As such, traded plastic waste could eventually enter the ocean through poor waste management systems.

But what about the plastic that is not recyclable — should we send it to landfill or incinerate?

Here, the winner is less clear-cut. As we see across the range of studies above: it depends on context, plastic type and conditions as to whether landfill or incineration has lower impact in terms of greenhouse gas emissions or energy use.

Both landfill and incineration have potential environmental risks if they’re not managed or regulated correctly. The best choice may depend on local context.

Incineration for example, can have a net positive on greenhouse gas emissions if burned efficiently and is utilised in a fossil fuel dominant energy mix. Across some countries — many across Europe — incineration efficiency is low and the energy mix is lower-carbon, meaning landfill may be more favourable.

Incineration may be favourable where fossil fuels are dominant, landfill space is limited or poorly managed, or subsurface conditions are unfavourable to landfills.

In either case it’s critical that proper management and regulation is in place to minimise environmental impacts.

Can recycling end up in landfill?

Unfortunately, yes. Some plastics intended for recycling end up in landfill.

There are several reasons why this can occur:

  1. In most countries, some share of plastics intended for recycling are eventually rejected at local or regional waste handling facilities. The most common reason for rejected recycling is the ‘contamination’ of recycling streams this can result from high concentrations of non-recyclable items in the waste stream, or contamination of other forms such as food waste. Even in cases where plastic contamination could be dealt within, it is sometimes more economically-feasible to divert some loads to landfill. Processing costs of poorly-sorted or contaminated plastic loads are more expensive, in some cases outweighing profits from recycled materials.The rate of ‘rejected recycling’ can vary significantly between countries depending on recycling policies, targets and the effectiveness of recycling separation methods (either at the household and local collection level, or at waste handling facilities). For a sense of scale, latest figures For England estimate that between 3 to 4 percent of total household recycling (which is plastics but also paper, metals etc.) was rejected and sent to landfill or incineration. In relative terms, this share is relatively low but could be improved through better understanding of how to avoid contamination of plastic recycling streams.
  2. Recycled plastic is a globally traded commodity. The majority of major exporters are high-income countries. If we look at the top ten exporting countries over the period from 1988 to 2016, we see that collectively they account for 78 percent of global plastic exports (as shown in the chart below). All of the top ten exporters are defined as high-income. Collectively, they have exported 168 million tonnes over this period, equivalent to an economic value of US$65 billion. China has been the world’s largest plastic importer. Collectively, China and Hong Kong have imported 72.4 percent of all plastic waste (with most imports to Hong Kong eventually reaching China). In 2017, China introduced a ban on non-industrial plastic imports in part because of the levels of contaminated plastics in countries’ export stream. Some of this imported plastic therefore ended up in landfill (and possibly at risk of entering the ocean).It’s challenging to track the ultimate fate of traded plastics, however it’s likely that at least some of recycled plastics exported from high-income countries enters landfill in the countries to which they are traded.
  3. Following China’s ban on imported plastic in 2017, previous large exporters such as the United States, Canada, Australia and UK have failed to handle the increase in domestic plastic recycling demand. As such, some materials intended for recycling have subsequently been diverted to landfill.
  4. Plastics typically degrade in quality during the recycling process. For most recyclable plastics, they are typically only suitable for recycling once. As a result, most recycled plastic we use eventually reaches landfill, even if it goes through an additional use cycle as another product. Recycling typically delays rather than prevents plastic disposal to landfill or incineration.



More On Recycling Of Plastic

  • Make sure you check with your local council the best way to recycle
  • Different plastics can be recycled differently – The structure of the polymers also affect a plastic’s recyclability. Some polymers fail and break down under mechanical or thermal stress; this affects their ability to be recycled. Refer to graphic on this page for materials that are recyclable –
  • In practice, the majority of recycled plastics are only recycled once or twice before being finally disposed of in landfill or incineration. In recent years there has been promising progress in the development of polymer materials which can be chemically recycled back to their initial raw materials for the production of virgin plastic production. In a recent study, Zhu et al. (2018) successfully synthesised a plastic with mechanical properties similar to commercially available plastics, but with infinite recyclability through chemical recycling. Such methods are currently expensive and unfavourable in terms of energy inputs, but could provide a commercially-viable solution in the years to follow.



Other Plastic Notes

  • Many plastics are defined as non-degradable, meaning they fail to decompose and are instead broken down into smaller and smaller particles. Materials can slowly break down through photodegradation (from UV radiation). Estimated decomposition times for plastics and other common marine debris items are shown in the chart below.
  • Fishing lines, for example, take an estimated 600 years to break down. Plastic bottles take an estimated 450 years.
  • Average decomposition time of different plastics can be found in –
  • There are bio degradable and oxo degradable plastics. The production of so-called ‘bioplastics’ or biodegradable plastics is currently very low: estimated at around 4 million tonnes per year (which would be just over one percent of global plastics production).
  • A key current challenge of biodegradable plastics is that they tend to need particular waste management methods which are not always widely available. In 2015, the United Nations Environment Programme (UNEP) published a report on the misconceptions, concerns and impacts of biodegradable plastics. It concluded that: “the adoption of plastic products labelled as ‘biodegradable’ will not bring about a significant decrease either in the quantity of plastic entering the ocean or the risk of physical and chemical impacts on the marine environment, on the balance of current scientific evidence.”
  • There’s new plastic based technology and solutions like bacteria that eats plastic
  • There are both primary and secondary microplastics
  • One challenge of micro-plastics is that their small size makes them easier to (consciously or not) ingest. Ingestion of micro-plastics could have detrimental impacts on wildlife health.




1. Hannah Ritchie and Max Roser (2018) – “Plastic Pollution”. Published online at Retrieved from: ‘’ [Online Resource]




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