Over the years, the term ‘microplastics’ has become ubiquitous in the language of sustainability. But how much do we know about the nuanced problems that microplastics create? The term has made its way into common parlance, which means we all need to work harder to understand what impact that has on the environment as well as human and animal health.
What are microplastics and why are they harmful?
Microplastics are defined as small pieces of plastic that measure less than five millimetres in length and are mostly invisible to the naked eye. It’s important to debunk two common myths about microplastics. First is that they ‘degrade’, which can often be misconceived as ‘biodegradable’. They are not. Microplastics do disintegrate, i.e. breakdown, which is how they become micro by default. But they do not biodegrade. A material is only biodegradable if it breaks down with the help of microorganisms (e.g. microbes, algae, fungus) in a natural environment and returns back into the soil as a natural component. As we know from their pervasiveness in the conversation around sustainability, microplastics are quite literally going nowhere.
Another common myth is that all microplastics are the product of larger pieces of plastics gradually breaking down. While this is how some microplastics are created, these are actually known as secondary microplastics. Troublingly, primary microplastics are micro by design. This means they were intentionally designed to be this small and are most often found in commercial products that might be used for cosmetic ingredients.
This poses the problem of packaging contributing to the presence of microplastics. Considering that around 40% of global plastic is used in packaging, it’s hardly surprising. Of course, single-use plastics are the biggest culprits. Designed to be useful for a short amount of time, these plastics end up becoming long-term environmental pollutions; their design cannot contend with the impact. The crux of the issue is packaging design that cares more about its use (i.e. protecting or housing a product) rather than its end of life (i.e where does it go when it’s inevitably discarded, and what will eventually happen?).
As more plastic is thrown away and pollutes our environments, the existence of microplastics grows. Recent research has shown that simply opening plastic packaging through twisting caps, cutting with scissors or tearing packaging with your hands can generate microplastics. The prevalence of plastic pollution means that these non-biodegradable materials will simply disintegrate, producing millions of microplastics that further pollute the environment. The Great Pacific Garbage Patch is a concerning realisation of our collective contribution to marine plastic pollution: 1.6 million square kilometres of plastic waste sits in the middle of the Pacific Ocean, with microplastics accounting for much of the debris.
So by now we know that there is a problem, but what about why it’s a problem? On a global level, microplastics greatly affect the environment, human health and animal health, in visceral and visible ways.
How do microplastics enter soil and marine environments?
There are various pathways through which microplastics can enter either marine or soil environments. Some of these are ‘natural’, through rainfall or wind; others are more intentional through human use, like littering or landfill; and some can be unintentional through human use, like physical wear or washing.
Rainfall can transport microplastics by carrying them into fields, streams and oceans; and washing synthetic fabrics (like fleece) in washing machines or using certain cosmetic products (like facial scrubs that contain microbeads) can enter the water stream. As plastic packaging is characteristically light, it’s easily moved by wind across distances of up to 100 kilometres. Physical wear during product use can also produce huge amounts of microplastics – the wear on tyres from driving a car will generate 6.1 million tonnes of microplastics globally per year.
And while littering – improperly disposing of a plastic product – is a more obvious case of setting up the foundations for microplastics, disposing of plastic in the ‘correct’ way can still lead to landfill. Where microplastics can be released into the environment through a substance called ‘leachate’: a contaminated wastewater that is created when microplastics and hazardous chemicals come into contact with ground water or rainfall in a landfill, and that can “run off” to contaminate the surrounding environment.
What is the real impact of microplastics on the environment?
We primarily see headlines in the news and hear discussions about how microplastics pollute our seas. They do, and this is a major concern for a lot of reasons; but they also hugely affect our soil ecosystem which is similarly threatening. When microplastics enter the soil, they can decrease microbial activity and increase soil pH levels, which in turn creates poor conditions for native plant species and necessary crops to grow.
Not only this, but it’s been discovered that plastic concentrations in the soil also increase water evaporation rates. Why is this bad? It’s all connected to the rising temperatures associated with climate change; this increased water evaporation in the soil will heighten the risk of soil drought and reduce crop yields as a result. All roads lead to stunting crop growth which has a ripple effect on both the environment as well as human and animal food chains.
So while our ancestors had the Metal Ages, we have entered The Plastic Age.The growing entry of microplastics into our environment only further cements our position in the Plasticene Era, which refers to the possibility that plastics will eventually become embedded into the earth’s geological layers. As landfills become bigger and weightier, plastic will simply become buried, or will make its way into oceans furthering the already rising levels of marine plastic pollution.
How do microplastics affect animal health and marine life?
There are plenty of toxic chemicals found in microplastics, and direct exposure (i.e. ingesting these materials) can have extreme health effects on animals and marine life, depending on where they sit on the food chain. Overall, marine life are much more likely to be exposed to microplastics and are ‘highly susceptible’ to the bioaccumulation of microplastics.
Bioaccumulation refers to a higher concentration of a chemical in a biological organism (e.g. marine animal) over time, compared to the chemical’s concentration in the environment, so this means marine animals are ingesting the microplastics within their food source at a faster rate than they can be excreted.
When it comes to the food chain, those at the bottom are likely to ingest microplastics, which means that those higher up the food chain are then exposed to microplastic ingestion. So, what does that mean for the animals? A decline in fertility and feeding behaviour and increased oxygen consumption; and in fish, microplastic pollution can structurally damage their intestine, liver, gills and brain, too.
How do microplastics affect human health?
There are three ways that humans can be exposed to microplastics: ingestion, inhalation and skin contact. This could look like food consumption through ingesting certain marine animals that have microplastic bioaccumulation or even the residue from plastic packaging; inhaling airborne particles, or simply applying cosmetic products with embedded microplastics. Most concerning of all is the recent discovery that microplastics have been found in human placenta, human blood and breast milk. It goes without saying that the toxicity of microplastics is very dangerous, and these findings show that we are being exposed to this from in utero and throughout our lifespan. These toxic effects can manifest in our health in different ways, from neurotoxicity (when exposure to toxic substances alters the normal activity of the nervous system) to reduced immunity. While there’s still more research to be done, there have been reports that exposure to microplastics may increase the risk of cancer.
Why Vivomer doesn’t create microplastics.
We’ve developed a material called Vivomer which is an alternative to conventional, petroleum-derived plastics. Crucially, Vivomer does not create microplastics at the end of its life. This is because Vivomer is compostable and biodegradable; it breaks down with the help of microbes in a natural environment, returning the material back into the environment as natural components, effectively regeneratively feeding the earth with the same microbes. That’s because Vivomer is made with the microbes from the same family as those found in marine and soil environments. These microbes break down all polymer material into bacterial biomass (bacteria and fungi) and carbon dioxide, methane and water, which are all natural constituents. That means zero microplastics. Vivomer’s biodegradability is what ensures that persistent microplastics are not emitted into the environment. It’s what gives us our sustainability credentials.
Ultimately, what needs to change is not the way we produce, recycle or get rid of plastic, but the materials we use in the first place. There will always be a place for plastic in our lives, but it’s not necessary in all its forms, and there are ways we can design products in order to eliminate unnecessary plastic; whether it’s using a material like Vivomer that’s biodegradable, or consolidating components so there are less plastic elements out there in the world. Microplastics are a macro problem and cannot be ignored. Their persistence in the environment and the way they can filter into our soil ecosystems, marine life, food chains and our own bodies makes them a real threat.
If we don’t intervene, plastics are expected to account for 85% of marine litter, at a rate of 50 kilograms per metre of coastline by 2040. And although a precedent has been set to take collective action against plastic pollution and microplastics by global initiatives from the United Nations, European Union, North America and China, there is still a strong case for the industry and key decision makers to transition to materials that won’t leave microplastics behind.
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