Originally perceived as a marine issue, with oceanographers estimating a total of 15–51 trillion microplastic particles floating on surface waters worldwide, scientists have recently discovered that these tiny particles can contaminate rivers, soils and air. Furthermore, these minuscule particles have been found in a range of food, human stool, and even made their way into some of Earth’s most remote regions; including the poles, the equator, and even Mount Everest.
Plastics are a group of materials, either synthetic or naturally occurring; used in numerous applications in our daily life. They are the third most abundant material, after concrete and steel, and are used in countless sectors; ranging from medicine to transport.
Microplastics are microscopic fragments of plastic debris, that usually emerge from plastic litter due to sunlight exposure, which causes the material to degrade and weaken over time; they can also come from plastic items due to wear and tear. For instance, up to 1.5 million microfibres, a type of microplastic, can be released per kilogram of clothing during a wash. Remarkably, even opening a plastic bottle can create thousands of microplastics. One may ask, are humans ingesting these minute particles?
The short answer is: yes, with the discovery of microplastics found in stool verifying this question. As of today, microplastics have been found in foods and drinks, mainly bottled and tap water, salt, dust, and more. According to a study conducted in Queensland, researchers studied samples of rice from different countries around the world, detecting microplastics in every sample; whether the rice was grown in Thailand, India, Pakistan, or Australia, and packaged in plastic or paper. In an interview, Dr Jake O’Brien, a lead author for Environmental Health Sciences, states “Washing the rice reduced the amount of plastic likely to be ingested. But the study used special filtered water for rinsing, and most households only have access to tap water; which contains microplastics.”
There currently isn’t enough evidence to say that microplastics are harmful, as the topic is relatively new. A lack of information and research surrounding the phenomenon is scarce, as scientists aim to establish an evidence base. Prof Ian Musgrave, a toxicologist at the University of Adelaide, expresses “Knowing if microplastics are harmful to humans is hard to untangle when we are exposed to so many other substances. While we are consuming things that have tiny amounts of microplastics, we don’t absorb them. But because we can’t demonstrate damage, that’s not a reason to be casual.” Additionally, this explains why multiple studies on the ingestion of microplastics by marine animals, can’t completely isolate the impact microplastics have against all the other pollution and pressure they are exposed to in the environment, as it’s difficult to perform.
Likewise, there are emerging studies on the effects of ingesting high levels of microplastics in rats and mice, concluding that high levels of microplastic accumulation can affect reproduction. Nevertheless, it is more likely that the smaller the particles the greater the potential to cause harm, as smaller specks have an easier chance of entering cells or tissues; however, quantifying these issues and understanding where they come from is a challenge.
While the debate is still ongoing as to whether microplastic could cause harm, you may still wish to limit your exposure. To limit your exposure, you can drink filtered tap water, and choose natural-based products over plastic for yourself and your environment will help reduce microplastic exposure. Overall, minimising microplastic exposure globally requires a substantial effort to limit the release of plastics, and microplastics, to the environment. Reducing plastic waste, washing your clothes less often, and bringing your own bag whilst shopping; all can contribute to limiting plastic release and even production; thus decreasing microplastic exposure.
Whatever the solution, it’s important that it’s better for both the planet and people.
