By Liam Prince, Emily Joy Frost, Ursula Rojas & Mark Lungley

Plastics are big news: the Government has just announced they will phase out a range of single-use and hard-to-recycle plastics. Plastic Free July is upon us. But are you someone who wonders what all the fuss is about? 

While we might all be somewhat familiar with the problems plastic pollution poses on ourselves and on the environment, how big are these problems really? Do they outweigh the benefits of plastics on balance? Are the seemingly zealous campaigns to ban single-use plastics that are choking wildlife and making their way into our food chain justified? The reality could be much worse than we might think.

Litter pollution

Many people’s experience with plastic pollution is as litter – bottles, cups, straws, packets, containers, lids and more – found in the gutter, next to highways and in our waterways and oceans.

Many would have seen the harm plastic causes to wildlife – choking, strangling, suffocating and starving animals unlucky enough to encounter the stuff or confuse it for food. Plastic pollution is an ever growing threat to the marine environment, impacting a number of vulnerable species

The latest research has confirmed that plastic debris has infiltrated every marine environment, including both poles through to the deepest part of the ocean, the Mariana Trench (10,898 m).

A study conducted by the Ellen MacArthur Foundation in 2016 estimates that by 2050 there will be more plastic in the sea than fish by weight. Data shows that 32% of the 78 million tons of plastic packaging produced annually is left to flow into our oceans – approximately eight million tons a year. That’s roughly one garbage truck full of plastic entering our oceans every minute. To date it is estimated that 150 million metric tons currently pollute our oceans.

If business as usual continues it is projected that, instead of one garbage truck per minute we will have four garbage trucks worth of plastic entering marine ecosystems by 2050. This will exponentially increase the impact on all life within our oceans, from plankton to blue whales.

Plastic consumption by marine species is not new – it has been recorded since the 60s and 70s and scientists have been warning us about plastic pollution without success until recent years.

Currently, at least 92 species of fish have been reported to ingest plastic. This is expected to affect the fishing industry sooner rather than later, because of the reduction in fishable stocks (fish and shellfish populations) and the potential implications on the safety of consuming seafood.

It has been estimated that at least 640,000 metric tons per year of fishing gear are lost somewhere in the ocean, contributing to the amount of plastic in our waters. This also produces the ‘ghost fishing’ phenomena, where abandoned fishing gear indiscriminately catches and kills marine life, including dolphins.

But plastic pollution is not just what we see. There is a hidden threat in the form of microplastics and nanoplastics, pieces of plastics smaller than 5mm and one micrometre respectively.

Some of these come from larger plastics degrading in sunlight and forces of nature, but the biggest source of these are what are known as ‘primary’ microplastics – stuff that arrives in the environment ready-made in its microscopic size. It’s estimated the biggest sources of these are from the wear and tear of tyres and from synthetic micro-fibres – things like polyester and nylon used for clothing and textiles.

This is a huge concern for oceans, because studies have found that 94% of microplastics and nanoplastics DO NOT FLOAT! Plastic particles lack buoyancy, which creates serious threats not only for marine life, but also human health.

Research data explains that most of the plastic ingested by marine species is micro and/or nanoplastics. For instance, research conducted on fish in the North Sea found that 74% of the plastic found was microplastic – however, the plastic found inside of cod was as large as 50cm in length!

Another concern is the amount of microplastics found in plankton. In 2019, Jamieson and co found microplastic ingested by the tiny zooplankton Lysianassoidea in six trenches (depths ranging from 7,000m to 10,890m) around the Pacific including: Japan, Izu-Bonin, Mariana, Kermadec, New Hebrides and the Peru-Chile trenches. The scientists found ingested microplastics in 72% of the analysed samples. The collection included nylon, polyethylene, polyamide, rayon, lyocell, and others. The implications of the study? Plastics and microplastics have infiltrated every level of the marine food chain.

How does plastic even get in our oceans?

Around 20% of the plastic pollution found in our marine environment comes from marine activities such as fishing – the rest is from activities on land. There are different pathways for plastics to reach our marine environment, from rivers and estuaries to direct human discharge. Lebreton (2017) explains that each year rivers carry about 1.15 to 2.41 million metric tons of plastic to the oceans.

It’s really important to understand where the plastic comes from and how far it can travel. In this context, several research projects are being conducted to understand this using different models.

One of these projects is called the ‘Ocean Plastic Simulator’ developed by The Cawthron Institute and The Sustainable Seas Challenge. It is a web-based interactive tool that tracks how floating plastic waste moves around New Zealand’s coastline. In the tool it is possible to view where the plastic ends and/or accumulates after being transported many kilometres by ocean currents.

This is a free tool for learning, communication and public engagement that can support decision-makers and industry leaders to develop strategies and policies to tackle the issue.


What about the health impacts of plastics?

It cannot be disputed that plastics serve many useful functions in modern life: they are durable, malleable, and resistant to chemical, physical and biological degradation. However, the wide uses of plastics require numerous chemical additives to serve each individual purpose. In this case, plastics are, in every sense of the word, a risk, to both human and environmental health .

Bisphenol A (BPA), something that has become relatively well-known through the media, is a popular stabilising additive to a number of plastics. A 2003 estimate puts the output of BPA worldwide at 2.2 million metric tons, a large fraction of which comes into direct contact with food. This is a problem. Because combining the plastic matrix with BPA leaves some of the molecules unbound, BPA is able to be released from containers into food and drink over time. This is accelerated when containers are washed, or exposed to acidic foods.

While food is a major source of BPA exposure, so is inhalation. As a result of the large quantities of BPA produced globally, around 100 tons are being released into the atmosphere each year through synthesis alone. So what does this do to our bodies?

Routine assessments on the levels of BPA in the body have been rather alarming. It has been found that BPA levels in human blood and urine range from 0.1 to 10 µg/L. These levels have also been found in amniotic fluid and human colostrum and milk. In the USA alone, the CDC found that 92.6% of adults have detectable levels of BPA in the body, with males having higher concentrations on average compared to females.

Elevated levels of BPA in women and children are of particular concern due to the known windows of vulnerability that put developing foetuses and children at undue risk. So why is it so bad? Because it mimics estrogen. It binds to estrogen receptors, disrupting endocrine function.

Adverse effects of BPA include: changes in postnatal growth and development, altered sexual maturation, altered luteinizing hormone levels and decreased testosterone in males, increased prostate size, decreased sperm production and fertility, stimulation of the mammary gland in females, disruption of chromosome alignment in puberty, disruption of adult menstrual cycles, changes in immune function, decreased antioxidant enzymes in males, changes in behaviour, including hyperactivity, aggressiveness, pain and threat stressors, impaired learning and changes in maternal behaviour.

Unfortunately, BPA is not the only additive in plastics to cause such devastating health issues. A range of alternative chemicals developed to replace the function of BPA have been shown to cause the very same or equally damaging problems.

Another problematic family of chemicals is phthalates. These are a diverse group of compounds heavily exploited across various industries, especially plastics. They are incorporated into plastics as plasticisers to impart flexibility, pliability and elasticity. Unlike BPA however, phthalates are by design, not strongly bound to the plastic mixture, leaving them extremely susceptible to being released. Additionally, phthalates are present in plastics at incredibly high percentages, contributing up to 40%-80% of the overall weight

The large exposure risk of phthalates makes them of particular concern, especially as they too are endocrine disrupting compounds. Among the adverse health effects are changes in reproduction, insulin resistance, thyroid function and the immune system.

Owing to the unwanted effects of bisphenols, phthalates and more, there is a serious need to invest more research into additive compounds which would be safer for us, and the planet.

Climate change

It should be no surprise that greenhouse gas emissions occur at every stage of the plastic lifecycle. This includes extraction, transportation, manufacturing, incineration, waste treatment and pollution into the environment. Extracting and refining oil, coal and gas for plastic production emits more greenhouse gases than any stage. But the disposal of plastic waste is also problematic, with the incineration of plastics becoming a significant source of greenhouse gas emissions globally.

Apart from the direct emissions arising from the production and disposal of plastics, the process itself contributes to the ever increasing problem through a myriad of indirect effects. This includes: transportation, pipeline leakages and land use (clearing and impeding forests, and reducing carbon sequestration).

What about when plastics are released into the environment? In terms of climate change, plastics degrading in the environment slowly release greenhouse gases. Even the presence of microplastics in the ocean themselves hinder the ocean’s ability to absorb carbon dioxide.

So how big is plastic’s carbon footprint? At current growth rates, greenhouse gas emissions across the entire plastics lifecycle are projected to reach 1.34 gigatonnes per year by 2030 – emitting as much carbon as 295 new coal-fired power plants. By 2050, plastics will have been responsible for 56 gigatonnes of CO2e in total, which is 10-13% of the remaining carbon budget. This will seriously hinder the ability of the global community to maintain global temperature rise to 1.5 or even 2 degrees Celsius by 2100.

So what can we do to help mitigate this burgeoning problem? While recycling plastic waste can offset greenhouse gas emissions by reducing the raw material used, it is often impractical or even impossible to recycle many types of plastics – in fact, only 9% of plastics ever created have been recycled. Recycling plastic does not deal with the problems of toxic chemical additives, and recycled plastics might even be more toxic than virgin plastic.

And while alternatives such as biodegradable and compostable plastics have been increasing in popularity, there are major negatives to these too: there’s a lack of facilities that can compost them adequately (and instead they often end up in landfill where they emit methane), they add nothing of value to the resulting compost (and may even be detrimental to the composting process), they often contain some of the same potentially toxic chemical additives as oil-based plastics, and they often cause the same harms to wildlife and ecosystems when they end up in the environment.

With the World Economic Forum forecasting the production and use of plastics to grow annually at a rate of 3.8% until 2030, it’s clear that we can’t carry on with the same false solutions. So, what can we do instead?

What can we do?

We must not only rethink the way we use plastics, but how we use all of the earth’s resources. Swapping one problem material for another is not the answer – we need new and innovative systems that protect the health of both people and planet.

In short, we must shift towards a zero waste circular economy. This means redesigning products and systems that prevent and reduce unnecessary and problematic plastics at source, that replace current plastic use with new packaging and delivery systems and materials, and ensure that materials remain in use for as long as possible. Plastics will surely still play a role in a circular economy, but like it or not, we must drastically reduce the amounts and types of plastics we make and use. Remaining plastics should be much more heavily regulated to ensure materials and additives are safe, and that plastic products are consistently returned for reuse, refill and recycling, rather than being disposed of or lost to the environment.

There’s a role for consumer advocacy to achieve these things. Movements such as shop and drop and plastic attacks have attempted to hold those who make, use and sell unnecessary plastic packaging responsible for the waste they produce (a concept known as product stewardship). The “bags not” campaign was one of many initiatives that helped to highlight issues with single-use plastic bags in the lead up to the bag ban in 2018. Every year there’s also an ever-increasing amount of activity for Plastic Free July, and the number of zero waste stores is constantly on the rise.

And the Government is responding to grassroots action. The Prime Minister’s Chief Science Advisor produced a landmark report in late 2019 called “Rethinking plastics in Aotearoa New Zealand”. In response, the Government proposed and have now confirmed they will phase out a range of hard-to-recycle and single-use plastic items. A $50 million Plastics Innovation Fund has also been set up to “help New Zealanders rethink and redesign the way we make, use and dispose of plastic.” And the Government has already announced that a regulated product stewardship scheme for plastic packaging must be developed. And while these are important tools in the shift to a zero waste circular economy, they are only the beginning.

There’s no denying that we have a long, long way to go to stem the tide of plastic pollution. While there is no easy fix, we can and should take productive steps to redefine our relationship with plastics, and that is one big step in the right direction.

The writers are members of the Aotearoa Plastic Pollution Alliance (APPA

Liam Prince, The Rubbish Trip; APPA Chair

Dr. Emily Joy Frost, Research Fellow, Auckland University of Technology; APPA Member

Dr. Ursula Rojas Nazar, NIWA; APPA Member

Mark Lungley, APPA Member

Disclaimer: The ideas expressed in this article reflect the author(s) views and not necessarily the views of The Big Q.

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