It has been said that plastic is "one of the greatest inventions of the twentieth century", and a variety of plastic products have quickly entered every aspect of people's lives.
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However, the hard-to-degrade plastic piles up, floating on the surface of the sea, wrapped around the carcasses of animals... People have found that plastic is also one of the worst inventions, bringing us convenience and bringing us seemingly endless and insoluble pollution. Today, the pollution caused by plastics has added another one - microplastics.
Microplastics (MPs) refer to plastic particles with a diameter of less than 5 mm, ranging in size from a few microns to a few millimeters, and nanoplastics (NPs) with a size of less than 0.001 mm are usually included in this list.
Therefore, the often mentioned microplastics are usually microplastics and nanoplastic particles (MNP), micron plastics (1 μm-5 mm), sub-micron plastics (100 nm-1 μm) and nanoplastics (< 100 nm) that are not usually visible to the naked eye.
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People have understood the harm of plastics to humans and the environment, but there is some hindsight about the threat of microplastics, and after some scientists proposed it in the early part of this century, after more than a decade, the problem of microplastics has risen to the level of global governance. Scientists have detected microplastic contamination in both human blood and feces.
Researchers at the Medical University of Vienna studied the relationship between microplastics and the gastrointestinal tract, and published results show that if you drink 1.5 to 2 liters of water in plastic bottles, you consume nearly 100,000 microplastic particles in this way each year. But if tap water is chosen, the intake of plastic particles may be reduced to 40,000.
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Yes, plastics are everywhere in our lives, and microplastics are everywhere: primary microplastic particles (MNPs) that are directly present in the environment such as textiles, tire wear, cosmetics, etc. in the washing process, secondary MNPs produced by the crushing, wear or aging of plastic products such as plastic bottles, bags and fishing nets.
It may enter the human body through food such as marine life or sea salt, or it may enter the human body through plastic bottles ... Studies have shown that the global per capita annual intake of microplastic granules is about 5g, which is equivalent to a credit card.
Judging from the way microplastics enter the human body, the gastrointestinal tract is the organ that is most easily exposed to them. Studies have shown that microplastics alter the gut microbiome and are likely to interact with the host gastrointestinal tract at the cellular level through contact with intestinal epithelial cells.
It is a well-established fact that microplastic particles affect human health, but there is not enough data on their role in the pathogenesis of gastrointestinal cancer, which is the main route of exposure.
Although it is now understood that patients with chronic diseases are more susceptible to the adverse effects of microplastic particles, this is far from enough, the exact source of common microplastic types, the amount of excretion in the body, how doctors track them in the body, whether there are natural processes that can digest plastics, and what carcinogenic disease mechanisms microplastics trigger... These are all things that people want to know.
People not only want to understand, but also urgently want to understand, after all, our lives are still inseparable from plastic products, such as sterile syringes in the medical field, tape, blood bags and heart valves, etc. Have plastics and are currently irreplaceable. This means that microplastics enter our bodies through a variety of pathways every day.
We may not know enough about the microplastic particles produced by plastics, but it is urgent to address the various hazards caused by plastics as much as possible. Every step from plastic manufacturing to decomposition is worth studying, and ordinary people who can't do research have their own countermeasures, for example, starting with reducing the use of plastic products.