Plastic Ingestion: How Much Am I Consuming?

Plastic is everywhere, from the deepest depths of the ocean to the peaks of Mount Everest. It is in our food, water, and even the air we breathe. So, it is no surprise that we ingest plastic regularly. But how much plastic do we ingest? Estimates vary, with some studies claiming we consume up to 5 grams of plastic per week, the weight of a credit card. Others suggest a lower estimate of 0.1 grams per week. While the exact amount is difficult to determine, it is clear that plastic ingestion is a significant issue that may have harmful effects on our health.

Microplastics are in our bodies

Microplastics are everywhere, including in our bodies. On average, five grams of plastic particles enter the human gastrointestinal tract per person per week. This is roughly equivalent to the weight of a credit card. However, it is important to note that this estimate is based on limited data and may not be accurate for all individuals.

Microplastics have been detected in various parts of the human body, including the blood, lungs, breast milk, placenta, testicles, hearts, livers, and kidneys. The presence of microplastics in our bodies is a relatively recent discovery, and researchers are still working to understand the full scope of their impact on human health. While a few studies have linked microplastics to adverse health outcomes, such as cardiovascular disease and low male fertility, the overall understanding of their effects remains limited.

Laboratory tests have shown that microplastics can cause damage to human cells, including allergic reactions and cell death. Additionally, chemicals often found in plastics, such as bisphenol A (BPA), phthalates, and per- and polyfluoroalkyl substances (PFAS), are known to disrupt the body's natural endocrine system, which regulates processes such as growth, development, metabolism, and reproduction. However, there is currently no conclusive evidence to directly link microplastic exposure to specific health issues in humans.

While the health effects of microplastics are not yet fully understood, experts recommend taking precautions to minimize their ingestion. This includes avoiding plastic packaging when buying food, microwaving food in ceramic or glass containers instead of plastic, and ventilating indoor spaces to reduce the inhalation of plastic particles.

Plastic-infused drinking water

The extent of plastic consumption varies depending on the source of water. Bottled water, for example, has been found to contain tens of thousands of microplastic particles per liter, with an average of 240,000 particles, and sometimes even more. This is due to the plastic bottles themselves, as well as the potential for plastic contamination during the bottling process.

Tap water is generally considered to have a lower concentration of microplastics than bottled water. However, it is not entirely free of plastic, as the water may come into contact with plastic pipes and fittings during the treatment and distribution process. To reduce exposure to microplastics in tap water, some recommend boiling and then cooling the water before filtering it, although this may not be practical for everyone. Reverse osmosis systems are also promising for removing microplastics, but their components are often made of plastic as well.

To minimize plastic consumption from drinking water, individuals can take several measures. One option is to switch from bottled water to tap water, reducing exposure to the higher levels of microplastics found in bottled water. Additionally, individuals can opt to use reusable steel or glass bottles and tumblers when out and about, rather than single-use plastic bottles. At home, it is recommended to use glass containers for storing and drinking water, and to avoid using plastic kitchenware and food storage.

Plastic in food like shellfish

It is estimated that, on average, 5 grams of plastic particles enter the human gastrointestinal tract per person per week. This is roughly equivalent to the weight of a credit card. However, it is important to note that this estimate is on the higher end of the range, which could be as low as 0.1 grams.

One way that humans ingest plastic is by consuming shellfish, such as clams, oysters, and scallops, which have been found to contain microplastics. In 2016, a study was conducted by shellfish biologist Sarah Dudas and her students at Vancouver Island University. They planted thousands of clams and oysters across coastal British Columbia and, after three months, they found plastic particles inside these shellfish under a microscope. The majority of the microplastics found in the shellfish resembled those found along Puget Sound's shorelines, which are microfibers.

Mollusks, such as mussels, oysters, and scallops, have been found to contain the highest levels of microplastics among seafood. This is because they are bottom feeders, acting as a natural filtering system for the oceans, and are therefore more vulnerable to this type of contamination. Additionally, people may be exposed to a higher dose of plastic bits from consuming mollusks because they are typically eaten whole, whereas only parts of larger fish are usually consumed.

The presence of microplastics in seafood raises concerns about the potential health risks for humans. While the impact of ingesting microplastics is not yet fully understood, animal and human cell research has shown that microplastics can have adverse effects. There are also indications that microplastics can act as vectors for chemical pollutants and pathogens.

Plastic particles in human organs

It is estimated that, on average, five grams of plastic particles enter the human gastrointestinal tract per person per week. This is roughly equivalent to the weight of a credit card. However, it is important to note that this estimate may vary, with some experts suggesting that the actual amount of ingested plastic particles could be higher or lower.

The presence of plastic particles in human organs is a growing concern. Microplastics, defined as pieces of plastic smaller than 5mm in size, have been detected in various human organs, including the liver, kidney, brain, heart, breast milk, placenta, testicles, and spleen. These particles are believed to originate from the ingestion of contaminated food and water, inhalation of polluted air, and exposure to plastics in our daily lives.

Research has shown that ingested plastic particles can migrate from the gut into other organs and tissues. A study conducted by UNM researchers exposed mice to microplastics in their drinking water, equivalent to the amount humans are estimated to ingest weekly. The results indicated that microplastics had translocated from the gut to the liver, kidney, and brain tissues. Furthermore, the study suggested that microplastics altered metabolic pathways in the affected tissues, raising concerns about potential health implications.

While the exact health effects of plastic particles in human organs remain to be fully understood, some studies have linked microplastics to adverse health outcomes. These include cardiovascular disease, metabolic disorders, attention deficit/hyperactivity disorder, fertility issues, and certain types of cancer. The accumulation of plastic particles in the body and their potential to trigger local inflammation and immune responses are areas of ongoing investigation.

To minimize exposure to plastic particles, individuals can take measures such as avoiding plastic packaging, microwaving food in non-plastic containers, ventilating their homes, and using alternatives like stainless steel or glass for storing and consuming food and beverages.

Changes in gut microbiome

The human gut is a complex ecosystem, home to trillions of microorganisms, including over a thousand species of bacteria, as well as viruses, fungi, and parasites. This diverse community, known as the gut microbiome, plays a crucial role in maintaining overall health, influencing both the digestive system and other aspects of wellbeing.

However, the modern world presents a unique challenge to this delicate internal balance in the form of microplastics. These tiny plastic particles, measuring less than 5 mm in length, have infiltrated our environment, from the depths of the oceans to remote regions of Antarctica, and even our seafood. The ubiquity of microplastics means that they now season nearly all of our meals with a flurry of plastic particles and fibres.

While the exact amount of plastic humans ingest remains unknown, estimates range from five grams per week (the weight of a credit card) down to a fraction of that. The weight, however, may be less concerning than the size. Microscopic plastic fragments, sometimes smaller than individual bacteria, can penetrate human cells and pass from the gut into the bloodstream.

Preliminary studies on the impact of microplastics on the human gut microbiome suggest that they can alter the permeability of the intestine and change how we digest food. They also appear to disrupt the gut microbiome, shifting it towards an unhealthy state. This disruption can have far-reaching consequences, as the gut microbiome plays a pivotal role in digestion, immunity, and overall health, including weight loss, heart health, and brain health.

Research on seabirds provides additional insight into the potential harms of microplastics. Studies have shown that microplastic ingestion by seabirds leads to a higher diversity of bacteria in their guts, including an increase in antibiotic-resistant and disease-causing bacteria. These findings suggest that microplastics may act as vectors for bacteria, potentially introducing pathogens into the gut and causing a shift in the microbial balance.

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