The increasing production of plastics and the buildup of plastic waste around the world has resulted in microplastic contaminants in water and food supplies. Existing plastic waste is subject to degradation by the environment, including from sunlight. This process makes the plastic brittle and breakable. The material that does not fully decompose will turn into small pieces called microplastics.
Microplastics are defined as plastic particles less than 5 mm in diameter, and include nanoplastics that are smaller (less than 1 μm). Single-use polystyrene products, such as foam packing materials, cups and tableware, contribute to overall plastic waste. There are two types of microplastics: primary microplastics, which are produced for specific products used by humans (such as soaps, detergents, cosmetics, and clothing), and secondary microplastics, which come from the decomposition of plastic waste in the ocean. Both types of microplastics can remain in the environment for a long time and have an impact on human health. Based on the results of Ecological Observation and Wetlands Conservation research, it was found that microplastics can enter the human body through breathing, digestion, and exposure to plastic objects that have weathered.
Microplastics can be swallowed by very small living things, such as bacteria, amoebas, and plankton that live in waters until they are eaten by predators such as fish or other aquatic animals, so that they will experience hoarding in the body of these predatory animals. Then microplastics can enter the human body, one of which is through food, for example by consuming fish or aquatic animals contaminated with plastic waste, the use of salt when preserving fish, or through the use of food / drink containers made of plastic.
Some common types of microplastics that contaminate food include;
- Bisphenol-A (BPA). A chemical used to produce strong polycarbonate plastics, such as in food containers and hygiene products.
- Phthalates. Chemicals to produce flexible, transparent, and durable plastics such as in food containers.
- Dioxins. A chemical that is a by-product of herbicides and paper bleach that pollutes the environment.
- Polyethylene and Polypropylene. Chemicals for plastic food packaging, such as polyethylene terephthalate (PET), high density polyethylene (HDPE), low density polyethylene (LDPE), and polypropylene (PP).
Microplastic deposits in the body are foreign body deposits that cannot be digested or absorbed by the body, which can cause irritation. If left too long, inflammation will occur which can even trigger the onset of tumors and even cancer.
One study also found that there is a link between nanoplastics and Parkinson's disease and dementia. In mice, nanoplastics combine with α-synuclein fibrils to exacerbate the spread of α-synuclein pathology across interconnected vulnerable brain regions, including a strong induction of α-synuclein inclusions in dopaminergic neurons in the substantia nigra. These results highlight a potential link between nanoplastics and α-synuclein aggregation with Parkinson's disease and dementia.
Parkinson's disease (PD) and related dementias are pathologically defined by the accumulation of the protein α-synuclein in vulnerable neurons in the brain. α-Synuclein is a low molecular weight protein, but in PD-affected tissues, electron microscopy studies show that the fibril structure interacts with damaged lipids of various organelles, such as lysosomes and mitochondria. With the increase of nanoparticles in the environment, studies related to the pathobiology of α-synuclein may provide insight into what types of nanoparticles need to be further explored as potential risk factors in PD. Among various types of plastic pollutants, the increase of polystyrene nanoplastics in the environment from single-use plastics, is a relevant particle type to explore for interaction with α-synuclein. Direct nanoplastic exposure can result in de novo formation of mature phosphorylated α-synuclein inclusions on dopaminergic neurons in the substantia nigra. These results highlight the emerging potential in anionic nanoplastics that can be further explored to better understand the possible role in Parkinson's disease risk and progression.
Currently, there is no research on how to tackle microplastic waste. However, we can start by reducing the use of the source of microplastics, namely plastic, in our daily lives, such as:
- Prioritize using non-plastic food containers when placing food or drinks
- Avoid drinking beverages that use plastic bottles or plastic packaging
- Avoid heating food in plastic containers as the plastic will decompose and can leach into the food.
Let's raise awareness to reduce the use of plastic and always dispose of waste, including plastic waste, in its place.
Image: Illustration (Source: Freepik)
Reference:
- Rahmawati A. Microplastics: Its invisible form and unexpected impact [Internet]. 2023 Jun 14 [cited 2023 Nov 28]. Available from: https://ayosehat.kemkes.go.id/mikroplastik--wujudnya-tak-nampak-dan-dampaknya-tak-terduga
- Liu Z, Sokratian A, Duda AM, Xu E, Stanhope C, Fu A, et al. Anionic nanoplastic contaminants promote Parkinson's disease-associated α-synuclein aggregation. Science Advances [Internet]. 2023 Nov 17 [cited 2023 Nov 28]. Available from: https://www.science.org/doi/10.1126/sciadv.adi8716
