Microplastics are Detrimental to Animals: How about humans?

With the talk of microplastics and their potential danger for humans circulating around social media and the public health world, many may wonder whether they should be worried. Plastic waste  has been accumulating rapidly in the environment since they were first observed in the Earth’s oceans in the 1960s. Hence, they have made their way into the bodies of millions of marine organisms and even land organisms including humans. The question is whether microplastics pose a threat to human health. Do they really disrupt the endocrine system? Do they damage the liver? Can they even inhibit reproductive health? 

What are Microplastics?

Before answering those questions, it is important to define what microplastics really are. Microplastics refer to microscopic plastic particles ranging from a few micrometers to 5 millimeters in size. Generally, the concern comes with samples that are under a millimeter in size, as this is when they become difficult to catch. Due to many plastics either being non-biodegradable or requiring decades to decompose, microplastics have begun to accumulate almost everywhere, including the air, ocean, andwithin organisms. Additionally, most commercial food products are now packaged in single-use plastic, further contributing to the buildup of plastic waste in the environment and exposing humans to microplastics.

How do they affect animals?

In recent years, scientists have begun researching the buildup of ocean microplastics and its impact on marine life. Experts have observed that the deep ocean and Arctic glaciers serve as “huge sinks for these particles” (Parker, 2022). Studies on fish and other marine life have concluded that microplastics pose giant threats to the ocean’s food webs and biodiversity. These small particles block the digestive system, contributing to malnutrition. They also leach into the bloodstream and potentially cause neurological damage, changing behavioral patterns. Lastly, they stunt growth and can cause the loss of critical senses. While these studies pose many concerns regarding the widespread use of plastic, it is important to note that the field of study is relatively new and not thoroughly documented. 

What about humans?

A number of small-scale studies have concluded that microplastics are present in many regions of the human body, including feces and even the placenta of unborn babies. Further, a study at the Dutch National Organization for Health Research and Development found that microplastics can be transported via the bloodstream. Researchers at the University of Hull in the U.K. were surprised to find microplastics in the lower lung lobe. This may sound alarming, especially coupled with research conducted at California State University which found over 10,000 chemicals to be used in plastics, with over 2,400 of them being potentially harmful to humans in large quantities. However, scientists are not certain whether these smaller particles accumulating in the environment qualify as enough exposure to indicate harm, and will not be confirmed for many years to come according to Albert Rizzo, the American Lung Association’s chief medical officer. In the meantime, the question turns to this: How can we go about making plastics safer?

Works cited:

da Silva, V. H., Murphy, F., Amigo, J. M., Stedmon, C., & Strand, J. (2020). Classification and quantification of microplastics (<100 μm) using a focal plane array-Fourier transform infrared imaging system and machine learning. Analytical Chemistry, 92(20), 13724–13733. https://doi.org/10.1021/acs.analchem.0c01324

History and Future of plastics. (2016, July 18). Science History Institute. https://www.sciencehistory.org/the-history-and-future-of-plastics

Parker, L. (2022, April 25). Microplastics are in our bodies. How much do they harm us? National Geographic. https://www.nationalgeographic.com/environment/article/microplastics-are-in-our-bodies-how-much-do-they-harm-us