Microplastics Can Find Their Way Into Human Tissues and Cause Bodily Harm

Seemingly everywhere, microplastics are here to stay, polluting our bodies and the environment.

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Microplastics are produced during the manufacture, usage, and recycling process of plastic products. Once they enter the human body, they can cause various kinds of illnesses. Microplastics can cause respiratory and digestive problems, disrupt sleep, contribute to obesity, and increase the risk of Type 2 diabetes and even cancer.

Microplastics are plastic fragments in the form of blocks, filaments, or spheres less than 5 mm in diameter or length. They usually enter the body by way of inhalation, ingestion, and skin contact. Generally, fiber-shaped, and smaller microplastics are more toxic.

Studies have shown that ingestion of microplastics can cause damage to the intestinal wall, leading to inflammation, oxidative stress, and changes in the gut microbiota, which can lead to autoimmune diseases, cancer, and neurodegenerative diseases. Inhaling microplastics can cause irritation and damage to the respiratory system and may lead to respiratory diseases such as chronic obstructive pulmonary disease and asthma.

Skin contact with microplastics can cause itching and inflammation and may also lead to endocrine disorders and damage to the reproductive system. In addition to these direct health risks, microplastics can also carry concentrated portions of harmful chemicals and pollutants. According to a British research review, the health risks of exposure to microplastics constitute a long list, including hearing disorders, poor thyroid function, obesity, low semen quality, childhood asthma, increased risk of Type 2 diabetes, and many more.

In addition, microplastics in the environment can disrupt circadian rhythms and melatonin secretion, leading to sleep disorders. For its effect on obesity, some studies suggest that microplastics can disrupt hormone regulation and metabolism, leading to weight gain.

In July, a study published in Environmental Science & Technology found microplastics in heart tissue samples and blood samples from patients undergoing heart surgery.

The researchers collected heart tissues from 15 patients undergoing surgery and collected blood samples from the patients before and after the procedure. To study the presence of microplastics in the human heart and surrounding tissue the researchers used a laser direct infrared imaging system and electron microscopy scanning technology. The results showed that nine distinct types of plastic particles were identified in five different types of tissues, with the largest diameter reaching 469 microns. There were also nine types of plastic particles detected in pre- and post-operative blood samples with microplastics as large as 184 microns in diameter.

The study also found polymethyl methacrylate (a type of plastic) in the left atrium, epicardial fat tissue, and pericardial fat tissue of collected specimens.

In 1987, polymethyl methacrylate was classified as a Group 3 carcinogen in the list of carcinogens published by the World Health Organization’s International Agency for Research on Cancer.

Numerous past studies have shown that microplastics have been found in human blood, lungs, feces, and placenta. In 2022, researchers at Vrije Universiteit Amsterdam analyzed blood donation samples from 22 healthy people. It was found that 77 percent of the donors had quantifiable amounts of plastic particles in their blood, 50 percent of the blood samples contained polyethylene terephthalate (commonly used in plastic bottles), 36 percent contained plastic particles in packaging materials polystyrene (used in food and other packaging products), and 23 percent contained polyethylene (used in plastic bags).

Other studies have found that microplastics can attach to the outer membrane of red blood cells and may limit their ability to transport oxygen.

A study published in the magazine Atmospheric Environment in 2022 found that among 13 human lung tissue samples evaluated, 39 counts of microplastics were detected in 11 samples, from which 12 types of microplastics were identified, including polypropylene, polyethylene terephthalate, and resin, among others.

In addition, microplastic particles have also been detected in allergic rhinitis patients, and in the placentas of pregnant women.

Sources of Microplastics

Microplastics are seemingly everywhere and come from a wide range of sources, from large industrial products to medical devices and daily household items, including textiles such as nylon, acrylic, and polyester; cosmetics and personal care products such as exfoliating scrubs, and toothpastes; plastic packaging and containers such as beverage bottles, food containers; plastic bags; worn tires (when tires rub on the road, they release tiny rubber pieces containing microplastics); and paints and coatings which release microplastics into the environment during use and removal.

In addition, microplastics are also present in the air. A UK study showed that concentrations of microplastics are much higher indoors than outdoors.

Scientists have called on governments, businesses, and individuals to take action to reduce the use of plastic products and properly dispose of plastic waste in order to protect the ecological environment and people’s health.

Unfortunately, it seems that many people can no longer live without plastic. Virgin plastic production has increased from 2 million tons per year in 1950 to 367 million tons in 2020. It is expected by 2050, annual output will exceed 1 billion tons.

In addition, there is currently no method to completely disintegrate microplastics. Traditional plastic materials are difficult to disintegrate and can last hundreds or even thousands of years. Despite measures to reduce the environmental impact of plastic waste, including recycling, incineration, and landfilling, plastic pollution remains unavoidable. The overall recycling rate of used plastic is only 9 to 30 percent.

Scientists have proposed the concept of a plastic circular economy wherein plastics are reused, refurbished, and recycled as long as possible to reduce the release of polymer plastics into the environment. In 2022, the European Commission revised the bill to restrict the use of polymeric plastics in cosmetics. Many countries such as Canada and the United States have also proposed or implemented bans to stop the use of microplastics in personal care products.