Plastic In Our Bodies: How Much And What Now?

Plastic is everywhere in our lives, from the packaging of our food to the fabric of our clothes. When plastic breaks down into tiny particles, it can infiltrate our environment and our bodies. Microplastics, which are particles smaller than 5mm that slough off plastic as it degrades, have been detected throughout the human body, including in the blood, saliva, liver, kidneys, placenta, brain, heart, blood vessels, and digestive system. While the health risks of microplastics are still being studied, research in animals has shown that they can cause inflammation, cell death, lung and liver effects, changes in the gut microbiome, and altered lipid and hormone metabolism.

Microplastics are in our bodies

Scientists have long studied the impact of plastic on the ecological environment, and concerns have been raised about the health effects of some chemicals used in plastics. In recent years, researchers have discovered the extent to which microplastics have become embedded in the environment and in human bodies. Microplastics have been detected in fruits and vegetables, plastic water bottles, the air, cosmetics, household dust, and even human stool samples. They have been found in almost every part of the human body, including breast milk, the placenta, testicles, hearts, livers, and kidneys.

A recent study by Vethaak and colleagues found plastics in the blood of 17 out of 22 healthy blood donors, and a lung study found microplastics in 11 out of 13 lung samples. The plastic particles found were primarily nanoplastics, smaller than one micrometer, and small enough to have been inhaled or ingested. It is not yet clear whether such particles can pass from the blood into other organs, especially the brain.

While the health effects of microplastics on humans are not yet fully understood, a few studies have drawn associations between microplastics and poor health outcomes, including cardiovascular disease and low male fertility. Chemicals often found in plastics, such as bisphenol A (BPA), phthalates, and per- and polyfluoroalkyl substances (PFAS), are known to cause a variety of health problems, including cancers, metabolic disorders, attention deficit/hyperactivity disorder, and fertility issues.

In the meantime, researchers are working to fine-tune predictive models to describe microplastic concentrations in humans and to track how many microplastics people are exposed to each day.

Plastic particles are in the air we breathe

When inhaled, the largest pieces of microplastics are trapped in our airways' mucus and are moved along by hair-like structures called cilia until they are expelled through sneezing. However, smaller pieces can penetrate the body's defenses. If the pieces are smaller than 10 micrometers, they can reach the alveoli, where oxygen reaches the blood. These small particles can cause inflammation and potentially other chronic conditions. Microplastics smaller than 2.5 micrometers might even enter the bloodstream, which would allow them to spread to virtually any place in the body.

Scientists are still working to understand the full scope of the health impacts of micro- and nanoplastics, but they are concerned that microplastics may be linked to growing rates of cancer, heart disease, and other chronic illnesses. Microplastics have also been found to carry harmful chemical additives into the bodies of animals, and they are likely to do the same in humans.

The production and use of plastics are the undeniable cause of microplastics in the atmosphere. Without serious efforts to address microplastic pollution, the abundance of airborne microplastics will continue to increase.

Plastic is in our food and water

Microplastics can enter our bodies through various pathways, including the food we eat and the water we drink. They are released into the water from plastic bottles, shopping bags, and other plastic items that break down over time. Plastic fibres can also wash off our clothes and enter the water supply. When tap water from cities on five continents was examined, more than 80% of the samples were contaminated with plastic microfibres. People who meet their recommended water intake through tap water ingest an additional 4,000 plastic particles annually, while those who drink only bottled water ingest an additional 90,000.

Plastic is also present in the food we eat, as it can be found in commonly consumed items such as beer, salt, seafood, sugar, alcohol, and honey. The existing research on microplastics in food only represents 15% of the calories consumed by the average person. It is estimated that the average person may be consuming up to 5 grams of plastic per week, which is equivalent to a credit card. This includes plastic from food packaging, which can contain trace amounts of plastic that we ingest when consuming the food.

The health effects of ingesting microplastics are still being studied, and it is unclear how they might affect our bodies. However, research has shown that microplastics can act as a "vehicle" for harmful chemicals, carrying them into our bodies. They can also cause mechanical problems by lodging in organs and causing inflammation and physical damage. Scientists are working to determine the implications for human health and to develop models to describe microplastic concentrations in the body.

Plastic is in our homes

Plastic is everywhere in our homes, from the clothes we wear to the furniture we sit on. It is in our food containers, water bottles, children's toys, and kitchen appliances. Even the couch we relax on can contain plastics that leach toxic chemicals into our bodies. The average annual plastic consumption in Western Europe is approximately 150kg per person, more than double the global average of 60kg. This means that we are constantly exposed to and ingesting microplastics through our food, water, and the air we breathe.

The problem of plastic pollution is not just an environmental issue; it is also a health concern. While the exact effects of plastic on the human body are still being studied, research on animal health has revealed worrying trends. For example, studies have shown that plastics can lodge in the organs of fish, causing inflammation and physical damage. In addition, microplastics can act as a "vehicle" for harmful chemical additives, carrying them directly into our bodies.

The chemicals used in plastic production, such as BPA, PVC, and phthalates, have been linked to potential health risks. BPA, or Bisphenol A, is a synthetic chemical used in food containers, water bottles, and drinking water pipes, and exposure to it has been found to be well above acceptable health safety levels in Europe. This is a particular concern for children, who are more vulnerable to the potential toxic effects of these chemicals.

However, it is important to note that not all plastics are harmful, and they do have beneficial applications in our homes. Plastic insulation, sealants, and other building products can make our homes more energy efficient while reducing heating and cooling costs. Plastics are also used in healthcare, helping to save lives and make medical care more affordable.

Nevertheless, the presence of plastic in our homes and the potential health risks associated with it should not be ignored. We can take steps to reduce our reliance on single-use plastics and choose reusable alternatives whenever possible. Home composting, for example, is an easy and effective way to reduce waste and contribute to a more sustainable lifestyle. By making conscious choices, we can reduce our plastic consumption and minimize the potential health risks associated with plastic exposure.

Plastic is harmful to human health

Moreover, microplastics have been found to damage cells in the human body, causing cancers, lung disease, and birth defects. They can also act as vessels for pathogens, increasing the spread of diseases. Recent studies have shown that microplastics are infiltrating brain tissue, indicating that there may be nowhere in the human body that is untouched by these harmful substances. The impact of plastic on human health is not limited to microplastics alone. The production and disposal of plastics contribute to environmental pollution, with plastic waste clogging our land, air, and waterways. This pollution has severe consequences for human health, as vulnerable communities living near plastic plants, such as those in "Cancer Alley" in Louisiana, experience higher rates of cancer due to exposure to toxic chemicals.

In addition to the direct health impacts, plastic pollution also poses a serious threat to marine life, with studies showing that sea birds and marine animals that ingest microplastics can suffer from blocked digestive systems and physical damage to their organs. These harmful effects on marine life then indirectly impact human health, as humans consume seafood that may be contaminated with microplastics and their associated chemicals. While the exact mechanisms and extent of these impacts are still being studied, the growing body of research highlights the urgent need to address plastic pollution and reduce plastic usage to protect human health and the environment.

Furthermore, the impact of plastic on human health extends beyond physical ailments. Plastic pollution is also an issue of human rights and environmental injustice. Marginalized communities, particularly those living near plastic production facilities, bear the brunt of the health consequences of plastic pollution. Additionally, infants and children are more vulnerable to the harmful effects of plastics due to the sensitive nature of early human development. Exposure to plastics during these critical stages can increase the risk of birth complications, lung growth issues, and childhood cancer. Therefore, addressing plastic pollution is not just about protecting the environment but also about upholding human rights and ensuring equitable health outcomes for all.

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