Are microplastics a threat to human health and life?

Image source: https://www.pexels.com/photo/assorted-plastic-bottles-802221/

Plastic is everywhere. It can currently be found in the widest variety of objects and products. Plastic is used to store drinks and food, as cosmetic packaging, nets, and bags. It can also be found in toys, paint, clothes, furniture, and tyres. We encounter plastics in our homes, on the street, in a lake, at the bottom of a river, near the summit of Mount Everest, in the Arctic, and even in a crustacean in the Mariana Trench. Plastic particles were found in a newly discovered species of crustacean (Eurythenes plasticus) seven kilometres below the sea surface. 

Such microbeads, which can now be found up to seven kilometres below the sea surface, are called microplastics. Microplastics are plastic particles that are less than five millimetres in diameter. A distinction is made between 1) primary microplastic, which is produced by humans in small quantities as a cosmetic ingredient or, for example, as a carrier material in air fresheners, and secondary microplastic and 2) secondary microplastics, which are formed by the breakdown of larger plastic products due to environmental factors such as wind, UV radiation, low and high temperatures, moisture, or mechanical friction.

Microplastics can be found in water, air, soil and in the human body. A University of Newcastle study estimates that the average person can consume up to five grams of plastic per week. Where does microplastic come from in the human body? Microplastic is emitted by everyday products. It can be found in all sorts of products in plastic packaging and can also be directly emitted from the surface of a plastic object. A study at the State University of New York in Fredonia showed that, on average, there were ten plastic particles per litre of water from a plastic bottle and three hundred and fourteen smaller particles that were probably plastic. In addition, people consume plastic particles from seafood. Not only packaging, but also food directly can contain these particles. Marine organisms consume microplastics found in water. This is the so-called bioaccumulation phenomenon, when larger and larger organisms, higher up the food chain, consume more and more particles of a given substance. It is estimated that the main sources of microplastic are road tyres, road dust and clothing. When clothes made of plastics such as polyester, nylon, elastane, or polyamide are washed, so-called microplastics are produced, which enter waterways and soils because sewage systems are unable to contain them. A report by the Institution of Mechanical Engineers shows that up to thirty-five per cent of microplastics in the oceans may come from textiles. 

Microplastics can be found in human blood and lungs. A recent study found that microplastic was found in 17 of 22 blood samples and eleven of 13 lung tissue samples. It can also reside in other internal organs, tissues, and cells. Is plastic therefore harmful? It is important to distinguish between theoretically safe plastic and plastic contaminated with various types of harmful substances. There are many types of plastic. Substances such as bisphenol A, phthalates and styrene are used in the production of some types of plastic. These are endocranially active substances which can negatively affect the functioning of the human endocrine system. Endocranially active substances often affect fertility. In addition, they have been found to negatively affect pregnancy. More research is needed to fully assess its effect on humans. 

The plastic and microplastics are increasingly polluting the planet and their effect illustrates chain reactions which happen in nature. Therefore, it is important to understand the effects of specific human actions and promote positive changes at every level. 

Resources:

https://dgist.ac.kr/en/html/sub06/060202.html?mode=V&no=d5eda97761a07a20f550fe663077b778&GotoPage=1

https://www.bbc.com/news/science-environment-4338903

https://www.bbc.com/news/science-environment-49295051?fbclid=IwAR3Q2KOqG_KIzMFX_FmJ5l5BfzZfIJ7_MRYmNjfLvtwkMI7yZy_HEOmK8OE

https://www.nationalgeographic.com/environment/article/microplastics-are-in-our-bodies-how-much-do-they-harm-us