Our oceans are trashed with tons of plastic; a fact well-known and understood by the general public. 60% of plastic is used only once, and 150 million tons of it has already infiltrated our oceans. But what isn’t yet widely known is a subcategory that deserves more spotlight: microplastics. Microplastics — defined as plastic particles 4.75mm — make up 92.4% of the global plastic particle count in our oceans, meaning that the majority of our ocean’s plastic is in the form of small floating particles.
So what generates microplastics?
One of the most common contributors, surprisingly, is our clothes. About 60% of our clothes are now made from cheap plastic materials such as Polyester, Nylon, and Acrylic. When these clothes get rinsed in a washing machine, they release millions of microfibers – tiny strands of plastic fall off the clothes into the waste waters of the machine. Most modern washing machines lack a filter fine enough to catch microfibers, allowing them to enter into the waters of sewage treatment plants. Treatment plant filters yet again fail to catch the fibers, which discharge with the waste water into marine habitats.
Another large contributor is the vast quantity of plastic debris that exists in our oceans. Plastic litter in our oceans breaks down overtime into tiny microplastic pieces that get picked up by currents or settle to the bottom of the sea floor. With about 8 million metric tons of plastic dumped into our oceans annually, the production of microplastics shows no sign of stopping.
But regardless of how microplastics end up entering our oceans, they have the potential to affect more than just our ocean waters. Once in the oceans, marine animals eat the microplastics. Studies have found microplastic particles in plankton — a food source for much of the ocean’s food web — and even fish sampled at super markets — a protein rich food source that 3.2 billion people on the planet rely on. Thus, unsurprisingly, microplastics have been found in human bodies, too. Microplastics are showing up everywhere and, yet, little is known about the health impacts to both marine and human life.
So far, scientific studies have yet to confirm conclusively that microplastics can be harmful. Some particles, around 0.15 mm, can easily pass right through a human digestive system. However it has been proposed that smaller particles have the potential to absorb toxic or harmful chemicals. When such particles enter into the human body, they could release these harmful toxins and clearly be damaging to human health. A study from Lund University in Sweden found that plastic particles could pass through the blood-brain barrier of fish, building up in the fish’s brain tissue, and cause behavioral disorders such as slower eating. So far, the scientific research surrounding the health impacts of microplastics is limited, but it isn’t too hard to believe that adding plastic to our diet wouldn’t be a good thing. Another study on the impacts of microplastics on fish found that when plastic particles are ingested in place of food, fish showed reduced growth and affected body condition. The effects on humans could be similar or complete different – no conclusive results have been found.
The lack of scientific research means little has been done to stop the pollution of microplastics. Currently, research groups such as the National Ocean and Atmospheric Association are studying the health impacts of such particulate, but there have been no prevailing scientific conclusions made. This makes the creation of policy fairly difficult until more research has been done. But there are some steps consumers can take to reduce their microplastic production.
A few things people can do on a local level include changing purchasing habits and installing a fine-meshed filter into their washing machine. Changing personal purchasing habits means being more aware of clothing material. For example, purchasing wool and cotton apparel is preferable as such materials do not contain plastics. When washing clothes that are made of plastic, special filters for washing machines can be purchased to capture microfibers from clothes. However, purchasing wool and cotton clothing as well as fine-meshed filters is costly and often not a practical solution.
On a larger scale, policy surrounding microplastics can be developed in order to make a lasting difference. Many cities are already banning plastic bags and plastic straws. Such items frequently end up in the ocean and break down into microplastics. Additionally, policies should be created to mandate washing machine companies like Samsung, LG, and Whirlpool to implement better catchment filters. This would take the burden off the consumer to purchase and install an expensive filter system.
With so much plastic in our oceans and now in the food chain, it is hard to imagine solutions that would have the magnitude needed to lower plastic debris. However, given the potential health and environmental concerns microplastics pose, it is essential we take steps towards finding an end to littering our oceans with trillions of microplastic particles.