Microplastic Pollution: A Silent Killer in the Making
Photo courtesy of LKI
I was only a few years old when Sri Lanka opened its economy in the late 70s. The influx of plastics into the island was among the few visible changes I remember happening immediately after. Plastic was cheaper, lighter and attractive (at least colorful) compared to the things made of metal or wood that we had back then. Before long, many traditional wooden and metal household items were replaced by plastics. Bags, cups, plates, decorative items and furniture (a few years later) were among the most common examples. This was not a change only seen in Sri Lanka; the 1970s was the decade plastics became extremely popular around the world. Coincidentally, we just opened the economic gates at the peak of plastic popularity, so it could flow into the country freely.
However, no one had any idea about what this new material would do to our waste stream. What waste stream? Life was much simpler back then; people didn’t have much to throw away anyway. After paper and glass bottles were reused and metal items were recycled (by those who did scavenging for living), the little leftover garbage was mostly biodegradable. Plastics on the other hand are not easily degradable and there was no second hand market for them either (not until recently). The popularity of plastics made drastic changes to the waste composition and it took the world another two decades to understand the environmental pollution it had caused over the years. This pollution is twofold: it happens at a macro level as well as at a micro level. The macro issue of large mismanaged plastic items rotting on land or in our oceans and other water bodies is a visible damage and something that may be fixed through proper and sustainable waste management. The micro issue is caused by the smaller plastic pieces – 5mm or less in size as per the current definition. While some are as small as a few micrometers (1 micrometer = 1/1,000 millimeter), you may have to use the nano scale to measure even smaller ones (1 nanometer = 1/1,000 micrometer). Their size makes microplastic pollution something extremely difficult to combat even with a good waste management system.
What exactly is microplastic pollution? To answer this question, let me take you to my mother’s kitchen in the late 1970s. The best observation I made as a kid was the chopping board. My mother’s wooden chopping board was soon replaced by a plastic one. Wooden or plastic, a chopping board always gets scratched with each knife cut and over time we lose little pieces from its surface. While a wooden one may disintegrate at a steady rate, plastic disintegration gets worse with time. I could make similar observations with some of the plastic cups and plates we had in the kitchen. There were visible signs of disintegration (mostly peeling off) when they were a few years old.
The real question is what happened to these tiny little pieces that get detached from the plastics. The simple answer is that they either ended up in our food or in the pile of common trash in the backyard. In other words, we have been feeding microplastics to ourselves and to our environment from the backyard to the soils and water bodies. Although the country was flooded with plastic items, we were never educated on the limitations of plastics and we were never told that we shouldn’t be using the same plastic item for too long. We were not alone; the whole world was in the dark on this topic until the extent of the microplastic pollution was discovered about 20 years ago.
Plastic has now become an integral part of our living and we are surrounded by thousands of plastic items that contribute to microplastic pollution. They are made of different materials/colors and can come in many different shapes, such as fragments, fibers, pellets, foams, films and more. Disposable utensils, water bottles, styrofoam cups and containers, hygienic products, some detergents, clothing, vehicle tires and cigarette buts are just a few examples to name. Mismanaged plastic waste is one of the largest contributors to the issue. A majority of the microplastics are created by breaking down larger plastics into smaller ones and these small pieces can be as small as a few nanometers. We all know how small a millimeter is; a nanometer much smaller and equal to a millionth of a millimeter. What this means is that a majority of the microplastics in our environment are not even visible to us. They are not only invisible but also undetectable and unstoppable by the water and wastewater treatment facilities. As a result, most of our drinking water (including bottled water) contains some microplastics. Water and food are easy pathways for microplastics to enter human and animal bodies. Recent scientific research has proven the presence of microplastics in pretty much every organ in the human body and even in breastmilk.
What exactly is the damage these microscopic particles can do to us and our environment? They are simply toxic to all living beings. Once ingested or inhaled, microplastics can roam around in the intestinal tract and the ones that are smaller than 150 micrometers can diffuse into the bloodstream and potentially disrupt immune response. A recent study reported that polystyrene particles that are 50 nanometers or smaller have the ability to enter the human brain as well. Microplastics in the environment can affect soil fertility and soil organisms living in it. For example, the ability of microplastics to affect development and mortality of earthworms has been established by now. The danger of microplastics is not limited to the material itself. During the production process, chemicals are added to plastics to enhance its performance such as strength, flexibility and stiffness. At least 2,000 of such chemicals (out of more than 10,000 that are used during plastic manufacturing) are known to be toxic. These chemicals continue to be present in microplastics when they enter human and animal bodies or the environment.
If plastic is this bad, shouldn’t we stop manufacturing it? There is no easy way to answer this question. Plastic has become a very useful, affordable and widely used material. It will have its place in the world until we find an alternative but there is no other candidate on the horizon to take its place: at least not yet. Until we find another solution, the best strategy we have is to use plastic material wisely and keep microplastic pollution at bay to prevent any further spread. We naturally tend to think that a proper waste management system (collection, treatment, and final disposal of waste) should be able to help us combat microplastics, like any other type of waste. Unfortunately, it is not the case. It can only be a partial solution, as microplastics are not only generated by the (mismanaged) plastic waste. Intentionally or not, we are also responsible for generating and releasing them to the environment. The microbeads that are present in some hygienic products is an example for intentional generation and release. Intentional production and usage can be prevented with policy measures. Fortunately, many countries have already taken measures to ban or control such intentional microplastic generation.
The unintentional generation of microplastics is the most complex part of the puzzle. The chopping board example, the lint shed by clothes during washing and drying and the wear and tear of vehicle tires are some examples for unintentional generation done by us. It is not even possible to list down all probable ways of microplastic generation simply because we still do not know the complete story of it. However, we should at least try to prevent the ones we can understand and are able to stop. It is true that we may not be able to stop microplastics being released by natural wear and tear of vehicle tires but we can make a conscious decision to have a wooden chopping board or refuse to use single use plastic items such as straws and plastic cutlery or carry a reusable water bottle rather than buying water sold in disposable plastic bottles. Another thing most of us easily forget is the number of unused and unattended plastic items we keep at home. These can be as small as old cups, plates, bottles or as large as plastic furniture that we hold on to for years. They all may look great and shiny in the beginning but all plastic items do tend to disintegrate with time and can become breeding grounds for microplastic pollution. Until a better solution is found either to replace plastics or combat microplastics, the general rule must be to avoid any indiscriminate usage of plastics in our lives.