Understanding Microplastics: Invisible Invaders

Plastic is an abundant material in modern life. Consequently, we have created a massive amount of plastic waste. It is estimated that 12 trillion (!) tons of plastic waste will be deposited in landfills or leaked into the environment by 2050.

Microplastics, as the name implies, are very small plastic particles. Specifically, they are plastic particles smaller than 1mm in diameter. But plastics can be much smaller! A subcategory of microplastics, nanoplastics, is defined as particles ranging from 0.001 to 1 micron in size (one-thousandth of a millimeter). Microplastics (and nano-) come from the degradation of larger plastic waste or are directly produced for specific uses, such as microbeads in cosmetic products. 

Microplastics present an environmental concern as they resist degradation. This resiliency allows microplastics to travel great distances. Further, microplastics have a larger surface area relative to their small size, which makes them a potential long-distance carrier for environmental contaminants, such as heavy metals. Microplastics can travel to us through our oceans (from plastic waste consumed by sea life that we later eat) or through the plastic bags and containers in which we keep our food, cosmetics, and drinks.

Microplastics can potentially be ingested, inhaled, or absorbed through our skin. Upon entry, microplastics can disrupt our bodily systems in various health-threatening ways. For example, evidence suggests oral microplastic ingestion can lead to intestinal epithelial damage. Thus promoting chronic intestinal inflammation, exacerbating inflammatory bowel disease, and contributing to the development of colorectal cancer. Further, there is evidence that microplastics can be incorporated into vascular plaques and contribute to the development of cardiovascular disease. 

All told microplastics have been detected in human tissue from multiple organ systems, including cardiovascular, digestive, endocrine, integumentary, lymphatic, respiratory, reproductive, and urinary systems. This highlights the great potential impact of microplastics on interrupting normal body function and potentially causing disease.

Reducing Microplastic Exposure: Practical Steps

Microplastic exposure sounds pretty scary! Is there anything we can do about it? Given the ubiquity of plastics in our lives, it is impossible to avoid contact with microplastics. The best you can reasonably accomplish is to reduce the quantity of microplastics you encounter. 

Some practical steps to reduce your level of microplastic exposure include:

• Avoid single-use plastics (e.g. to-go containers, single-use water bottles)
• When dining on seafood, choose smaller fish (sardines don’t live long enough to absorb as many plastics microplastics as tuna)
• Wash your produce before consuming
• Avoid heating food in plastic containers
• Store food in glass (or other non-plastic) containers
• Vacuum your living space regularly

Also of note: there is some controversy over the extent of harm caused by microplastic exposure.  Nobody wants to have microplastics accumulating in our organs. However, some experts argue that the level of microplastic exposure in the environment falls well below the levels required for toxicity.     

In the future, developing technology, such as magnetic nanoparticles, has the potential to remove microplastics from water. This could eventually lead to infrastructure changes in water systems that could greatly reduce our exposure. In the meantime, taking practical steps to reduce microplastic exposure in your daily life, following the steps outlined above, can be easily accomplished.   

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