Microplastics have become one of the main pollutants of our marine ecosystems. These plastics are plastic fragments that are smaller than 5mm in length. It is very difficult to detect microplastics as some are too small to be recognized by naked eye. Microplastics are not different from any other plastics apart from the fact that they are very small. Like normal sized plastics, microplastics are durable and stable that makes it very hard to decompose naturally. Plastics are polymers that consist of a long chain of carbon and hydrogen. The problem of microplastic arises from not only the fact that it contaminates our ecosystem, but also the potential health risks that it may present to life on earth. We do not fully understand the effects of microplastic on the ecosystem and its impacts are still under research. However, what we know so far is that microplastics have the ability to absorb contaminants. While the ability of plastics to "clean up" contaminants may seem like a positive aspect, this ability can accumulate greater harm and pose threats to our ecosystem. When animals take in the plastic, this may create health risks to the animals which may consequently kill them. If animals do survive after the intake of microplastics, the plastic may be transferred to other animals at the higher ranks of the food cycle when the animals who consumed the plastics become prey to predators. 

How can we solve this problem? A possible approach for this problem can be tackling the wastewater treatment plants. Microplastics are commonly used in toothpaste or skin cleansers since microplastics exfoliate the dead skin cells and unclog skin pores. As people rinse after brushing their teeth or washing their faces, the microplastic that was inside the products then flows with the wastewater that leaves the household. While wastewater treatment plants should have the ability to filter and remove microplastics before releasing the treated water into a bigger body of water, studies show that these facilities do not have the ability to remove the plastics and have become one of the biggest contributors of releasing microplastics into water.

While there are physical filters that may be used to remove microplastics, the most recent technological breakthrough was made by using Fe-salts like the figure above. While previous methods focused on the physical properties of microplastics, we should now focus on utilizing the chemical properties of plastics as after all, plastics are chemicals that are made from polymers of carbon. This has also been the focus of   a research group led by Baiwen Ma that has utilized Fe-based flocs to remove small polyethylene particles, which are the main components of plastic. They have used PE particles to examine how Fe-based salts affect the removal of microplastics in water that undergo the process of coagulation, sedimentation, ultrafiltration, and disinfection in the traditional water treatment process. Their research has proven that PAM addition utilizing Fe-based salts contribute greatly in the efficiency of the removal process. The dense floc formation and high adsorption ability from the positively charged Fe-based flocs allowed the efficiency to increase tremendously. 

The team’s research has discovered a new behavior of microplastics when reacted with certain chemicals, which will lead to further applications in the removal of microplastics from drinking water and ultimately the marine ecosystem.

Works Cited:

Tox Town. “Microplastics: Your Environment, Your Health | National Library of Medicine.” U.S. National Library of Medicine, National Institutes of Health, 31 May 2017, toxtown.nlm.nih.gov/sources-of-exposure/microplastics#:~:text=Microplastics%20both%20absorb%20and%20give,pollutants%20by%20eating%20contaminated%20seafood.

Kay, P., Hiscoe, R., Moberley, I. et al. Wastewater treatment plants as a source of microplastics in river catchments. Environ Sci Pollut Res 25, 20264–20267 (2018). https://doi.org/10.1007/s11356-018-2070-7