The Hidden Dangers of Microplastics

For years, drinking from water bottles and using plastic containers seemed like a health-conscious choice. Plastic was seen as convenient, durable, and safe. However, recent research has begun to challenge this perception, especially when it comes to microplastics, or even worse nanoplastics—tiny particles that can enter our bodies through ingestion, inhalation, and even skin contact.

Difference Between Microplastics and Nanoplastics

Microplastics and nanoplastics are small plastic particles that have significant environmental and health impacts, but they differ in size and behavior.

• Microplastics: There is no officially published definition of microplastics, but in general they are plastic particles that range in size from 1 micrometer (µm) to 5 millimeters (mm). They can be primary microplastics, like microbeads used in cosmetics, or secondary microplastics, which result from the breakdown of larger plastic items. Microplastics are large enough to be seen with the naked eye and can accumulate in various ecosystems, leading to potential ingestion by marine life and humans.
• Nanoplastics: Nanoplastics are much smaller, typically less than 1 µm in size, often in the nanometer scale (1 nm = 0.001 µm). Due to their tiny size, they can penetrate biological membranes more easily, potentially causing more significant health effects. Nanoplastics are challenging to detect and study, making their impact less understood but potentially more hazardous than microplastics.

Both microplastics and nanoplastics can carry harmful chemicals and disrupt biological processes, but their difference in size affects how they interact with the environment and the body. Microplastics tend to accumulate in larger quantities in the digestive systems, while nanoplastics can penetrate tissues and organs more deeply.

Sources of Microplastics and Nanoplastics: Primary vs. Secondary

Microplastics and nanoplastics are pervasive in the environment, originating from a variety of sources that are broadly categorized as primary or secondary.

• Primary Sources: These are plastics intentionally manufactured at a small size. Common examples include microbeads used in cosmetics and personal care products, microfibers from synthetic clothing, and plastic pellets or "nurdles" used in industrial manufacturing. These particles are released directly into the environment through product use or industrial processes.
• Secondary Sources: These originate from the breakdown of larger plastic items such as bottles, bags, and fishing nets. Over time, exposure to sunlight, wind, and water causes these larger plastics to fragment into smaller particles. Secondary microplastics are not intentionally manufactured at their small size but result from the degradation of larger plastic debris.

Both primary and secondary sources contribute significantly to the environmental burden of microplastics and nanoplastics, with secondary sources often accounting for the majority due to the widespread use and disposal of plastic products.

The journey of discarded plastic

The journey of microplastics from production to human consumption is complex and concerning. Over 80% of microplastics originate on land, with less than 20% coming from marine sources. Due to their light and durable nature, these particles can travel vast distances across the globe, contributing to widespread environmental contamination. Processes such as thermal degradation, photodegradation, and hydrolysis ensure that microplastics persist in the environment, breaking down into even smaller nanoplastics. A single microplastic particle can fragment into billions of nanoplastic particles, suggesting a ubiquitous presence of nanoplastic pollution worldwide.

It is estimated that unless practices change, the amount of plastic entering the ocean by 2025 could be as high as 26 million metric tons per year. According to environmental advocacy group Ocean Conservancy, some plastics resist degradation so long they may be in a recognizable shape for up to 400 years.

​GREAT PACIFIC GARBAGE PATCH

Heavily polluted areas of the ocean are referred to as garbage patches, and now cover nearly 40% of the world's ocean surfaces. The Great Pacific Garbage Patch (GPGP) stands as a stark testament to the widespread pollution caused by discarded plastic, both large and microscopic. This massive accumulation of plastic debris is located in the North Pacific Subtropical Gyre, an area often described as "a gyre within a gyre," where ocean currents converge, trapping floating debris. The GPGP has grown to an estimated size of approximately 1.6 million square kilometers—about twice the size of Texas—and is so vast that it is now visible from space.

​Plastic waste, which comprises over 60% of less dense material than seawater, floats on the ocean's surface, driven by currents and winds. As these plastics travel across the globe, they encounter various environmental factors such as sunlight, temperature fluctuations, waves, and marine life, which gradually degrade them into smaller pieces known as microplastics. These microplastics are then transported offshore and become trapped within the circulating currents of oceanic gyres, particularly in the North Pacific.

The Great Pacific Garbage Patch has formed through the convergence of these buoyant plastics, accumulating in a vast area within the North Pacific Subtropical Gyre. This region, with its circular ocean currents, acts as a sink for plastic debris, drawing in and concentrating floating plastic waste. The result is a massive, swirling mass of plastic pollution that not only threatens marine ecosystems but also infiltrates our food supply.

​As plastics degrade in the ocean, they break down into microplastics, which are then mistaken for food by marine life. Fish and other sea creatures ingest these tiny particles, which then enter the food chain. When we consume seafood, we are also ingesting these microplastics, which can accumulate in our bodies over time. The presence of microplastics in the food we eat is a direct consequence of the plastic pollution in our oceans, particularly in regions like the Great Pacific Garbage Patch.

The Environmental and Health Impact

The Great Pacific Garbage Patch is not just an environmental disaster; it is a growing health concern. As plastics degrade and release toxic chemicals, they pose a threat to marine life and humans alike. These microplastics and nanoplastics do not simply pass through our bodies; they can accumulate in our organs, leading to long-term health effects. The vastness of the GPGP, combined with its persistent growth, highlights the urgent need to address plastic pollution on a global scale.

​Microplastics and nanoplastics are emerging as significant environmental contaminants with profound ecotoxicological effects on aquatic wildlife. These tiny plastic particles, which can result from the breakdown of larger plastic debris or be intentionally manufactured, have been shown to cause harm to marine organisms through a variety of mechanisms. The impacts are far-reaching, affecting everything from individual cellular functions to entire ecosystems.

Studies have demonstrated that plastics are so ingrained in the ocean food chain they have contaminated the bodies of living creatures from zooplankton to lobster, crab and fish — all creatures eaten by other animals further up the food chain. 

Mechanisms of Harm to Aquatic Wildlife

1. Physical Impacts:
   • Ingestion and Blockage: Marine animals often mistake microplastics for food, leading to ingestion. Once ingested, these plastics can cause physical blockages in the digestive systems of animals, reducing their ability to absorb nutrients and leading to starvation or malnutrition. For example, sea turtles, fish, and seabirds have been found with stomachs full of plastic, unable to process actual food.
   • Bioaccumulation: Microplastics can accumulate within the bodies of aquatic organisms over time. As these plastics move up the food chain, from prey to predator, they can reach concentrations that are harmful to larger species, including humans who consume seafood.
2. Biological Impacts:
   • Genotoxicity and Cytotoxicity: Microplastics have been shown to cause genetic damage (genotoxicity) and cellular toxicity (cytotoxicity) in aquatic organisms. The physical presence of these particles can disrupt normal cell functions, leading to mutations, cancer, or cell death. Studies have documented DNA damage in fish and invertebrates exposed to microplastics.
   • Oxidative Damage: Microplastics can induce oxidative stress by generating reactive oxygen species (ROS) within cells. This oxidative damage can lead to inflammation, impaired cellular functions, and even apoptosis (programmed cell death). Oxidative stress is a common pathway for toxicity in aquatic organisms exposed to environmental pollutants, including microplastics.
3. Chemical Impacts:
   • Toxicity Pathways: Microplastics often carry harmful chemical additives, such as plasticizers, flame retardants, and heavy metals, which can leach out and enter the tissues of marine animals. These chemicals can disrupt lipid metabolism, leading to energy imbalances and affecting growth and reproduction.
   • Neurotoxicity: The chemicals associated with microplastics can have neurotoxic effects, impairing the nervous system functions of marine animals. This can lead to behavioral changes, such as altered feeding habits, impaired predator-prey responses, and disorientation.

Specific Effects on Aquatic Wildlife

• Reduction of Feeding Activity: Ingestion of microplastics can reduce the feeding activity of marine animals, as their digestive systems become clogged with indigestible particles. This can lead to a decline in energy levels, growth rates, and reproductive success.
• Intestinal Damage: The sharp edges of microplastics can cause physical damage to the intestinal linings of marine organisms, leading to internal injuries, infections, and impaired nutrient absorption.
• Growth Delay: The energy required to process and expel ingested microplastics can detract from the energy available for growth. This results in stunted growth and developmental delays in juvenile marine species.
• Embryotoxicity: Microplastics have been found to impact the development of embryos in marine animals, leading to deformities, reduced hatching success, and impaired survival rates. Embryotoxicity is a critical concern for species with vulnerable early life stages.
• Behavioral Changes: Exposure to microplastics can lead to behavioral changes in marine animals, such as reduced feeding efficiency, altered swimming behavior, and impaired predator avoidance. These changes can have cascading effects on survival and reproductive success.
• Diseases in Marine Animals: Microplastics can serve as vectors for pathogens, carrying harmful bacteria, viruses, and parasites into marine organisms. This can lead to increased incidences of disease, further compromising the health of affected species.

The ecotoxicological effects of microplastics and nanoplastics on aquatic wildlife are not limited to individual organisms. The accumulation of these particles in marine environments can lead to broader ecological disruptions. For example, reduced feeding activity and growth delays in key species can affect the entire food web, leading to declines in predator populations and altering ecosystem dynamics.

Moreover, the persistence of microplastics in the environment means that these impacts can accumulate and intensify over time, potentially leading to long-term declines in biodiversity and the health of marine ecosystems.

The Great Pacific Garbage Patch is a glaring example of how our discarded plastic waste has come to dominate the world's oceans, creating a cycle of pollution that impacts both the environment and human health. As this floating mass of debris continues to grow, so does the urgency to find solutions to the plastic pollution crisis.
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Microplastics and nanoplastics are not just passive pollutants; they actively harm aquatic wildlife through a variety of mechanisms, including genotoxicity, cytotoxicity, oxidative damage, and neurotoxicity. These impacts, coupled with the physical presence of microplastics in the digestive systems of marine animals, can lead to significant ecological and biological disruptions, underscoring the urgent need for action to reduce plastic pollution in our oceans.

Microplastics in sea salt

In recent years, microplastics have become an increasingly concerning contaminant, even infiltrating the very salt we consume. A 2015 study published in Environmental Science and Technology revealed alarming findings: salt sold and consumed in China contained microsized particles of plastics derived from disposable bottles, polyethylene, cellophane, and other materials. Notably, the highest concentrations of these plastic particles were found in salt harvested from seawater.
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To put this into perspective, the study identified over 250 particles of plastic in just one pound of sea salt. Sherri Mason, Ph.D., a professor of chemistry at State University New York Fredonia, highlighted the ubiquity of plastic contamination, suggesting that it doesn’t matter whether you purchase sea salt from Chinese or American supermarkets—the issue persists globally. In fact, Mason went on to lead another study in 2017 that demonstrated Americans could be ingesting up to 660 microparticles of plastic annually if they adhere to the recommended daily intake of 2.3 grams of salt. Given that nearly 90% of Americans consume more salt than this, the actual intake of microplastics is likely higher.

Mason's research, conducted in collaboration with the University of Minnesota, analyzed plastics found in various consumer products including beer, tap water, and salt. They discovered that sea salt is particularly susceptible to plastic contamination due to its production process, which involves evaporating saltwater and leaving behind the solid salt—along with any microplastics present in the water.

Mason emphasized that this contamination is not unique to any one region, stating, "It's not that sea salt in China is worse than sea salt in America, it's that all sea salt—because it's coming from the same origins—is going to have a consistent problem." She urged consumers to reconsider their plastic usage and its pervasive role in our society, suggesting that addressing the flow of plastic into the environment is essential to curbing this widespread contamination.
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As consumers become more aware of the hidden dangers in everyday products, the need for alternative materials and reduced plastic consumption becomes increasingly critical for both environmental and public health.

A Word on the Benefits of Consuming Salt
Contrary to popular belief, consuming high amounts of salt does not necessarily lead to increased thirst or elevated blood pressure. In fact, studies have consistently failed to support these common assumptions. Instead, elevated insulin levels are the real culprit behind salt retention, which can lead to increased blood pressure. What drives up insulin? Refined sugars and carbohydrates. So, rather than blaming salt, it's more accurate to point the finger at sugar for these issues. Your body requires both sodium and chloride ions, the main components of salt, and it cannot produce them on its own. Therefore, it's essential to obtain these ions through your diet.

If you decide to follow a low-carb diet or engage in fasting, your insulin levels will naturally drop, leading to increased salt excretion through urine. This can cause dizziness, a common symptom when your body lacks adequate salt. The solution? Increase your salt intake. Feeling low on energy? Take salt. Experiencing headaches, brain fog, or difficulty focusing? Salt could be the answer.

Salt is an essential hydration mineral, and not getting enough can negatively impact your quality of life. Unlike some other nutrients, if you consume too much salt, your body simply excretes it through urine. In fact, drinking salt water has been associated with anti-aging properties. Maintaining healthy salt levels can boost your energy, improve sleep quality, reduce muscle cramps, and enhance exercise performance.
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Starting your day with 16 ounces of water mixed with salt can set you on the right path for maintaining optimal hydration and overall well-being. So, rather than avoiding salt, recognize its vital role in your health and use it wisely to improve your quality of life.

​However, it's important to note that not all salt is created equal. Refined table salt is almost entirely sodium chloride, often with added man-made chemicals. In contrast, unprocessed salts, like pink Himalayan salt, offer a more balanced mix of sodium and chloride, along with other essential minerals such as calcium, potassium, and magnesium. These minerals not only contribute to the pink hue of Himalayan salt but also provide additional health benefits.

LEarn more about the benefits of salt

Himalayan salt is mined from ancient salt beds that were formed long before the advent of plastic and other toxic chemicals. These salt deposits, once part of ancient ocean beds, were lifted during the formation of the Himalayan mountains and have since been protected by layers of lava, snow, and ice for thousands of years.

In comparison to salt harvested from modern oceans, which are increasingly contaminated with persistent organic pollutants and microplastics, Himalayan salt offers a cleaner, more natural option. If you're looking to reduce your toxic load, choosing Himalayan salt over conventional sea salt is a wise decision. If you are looking for sea salt, or Himalayan salt for that matter,  it's important to choose brands that are known for rigorous testing and purity standards.

Purchase (amazon): Himalayan Salt (Fine) -The salt lab

purchase (amazon): REdmond REal sea salt

Microplastics: A Growing Concern

Microplastics and nanoplastics are increasingly found in the environment and, alarmingly, within the human body. Until recently, the potential health risks of microplastics were largely speculative. Many believed these particles were too small to cause significant harm, passing through the body without issue. However, emerging research is beginning to paint a different picture.

Microplastics and nanoplastics have infiltrated various ecosystems—including oceans, freshwater bodies, and the very air we breathe—are increasingly recognized as a pervasive environmental and public health concern. These microscopic particles enter the human body through three primary pathways: oral ingestion, skin contact, and inhalation. Once inside, they have been found accumulating in vital organs such as the lungs, heart, liver, spleen, kidneys, brain, testis/penile tissue/semen, and feces, raising alarms about their potential long-term health impacts.

Pathways of Entry into the Body

Oral Ingestion: Microplastics and nanoplastics enter our bodies predominantly through the food and water we consume. Experimental sampling, such as Fourier-transform infrared spectroscopy (FTIR) on tap, bottled, and spring waters, has confirmed the presence of microplastics in all these sources, highlighting the pervasive nature of this pollution. Studies have detected these particles in everyday items like honey, beer, salt, seafood, and even mineral water. Recent research has shown that a single bottle of water (1L) can contain as many as 240,000 nanoplastic particles. These particles are introduced into the food chain as animals ingest them in their natural environments or as food is contaminated during production processes. Alarmingly, microplastics have also been found in human feces, underscoring their presence in our diet. While the evidence of their presence in food is growing, comprehensive quantitative data on human exposure through diet remains scarce, and no specific legislation currently exists to regulate micro- and nanoscale plastics in foodstuffs.

Inhalation: Airborne microplastics are another significant source of exposure. These particles originate from urban dust, synthetic textiles, rubber tires, and other sources. Due to their small size and lightweight nature, microplastics can remain suspended in the air and be easily inhaled, leading to their deposition in the respiratory system. Research has shown that microplastics can accumulate in the lungs, potentially leading to respiratory issues. More of this down below...

Skin Contact: Although less studied, skin contact represents another potential route of microplastic entry into the body. Microplastics are found in various personal care products, such as exfoliants and cleansers, which can penetrate the skin or be absorbed through wounds. The potential for microplastics to penetrate the skin barrier is an area of active research, with implications for chronic exposure and cumulative health effects.

Since these plastic particles do not simply pass through without consequence, but rather to accumulate in critical organs, the potential for these particles to cause harm is significant, as they can induce inflammation, disrupt cellular processes, and potentially lead to more severe health issues over time.

Implications for Human Health

The full extent of the health impacts of microplastics and nanoplastics is still under investigation. Most research to date has focused on pristine, intentionally manufactured particles, but the real-world scenario is far more complex. Environmental exposure includes aged and degraded plastics, particles coated with biofilms, and those that have absorbed various contaminants. These factors may alter the behavior and toxicity of microplastics, making them more harmful than initially assumed. 

The growing evidence of microplastic and nanoplastic accumulation in human organs and their presence in the food we eat and the air we breathe underscores the urgent need for more research and regulation. As we continue to uncover the extent of human exposure and the potential health risks, it becomes increasingly clear that addressing microplastic pollution is not only an environmental imperative but a public health priority.

Inhalation of air-borne microplastics

Recent research has revealed the alarming extent to which humans are exposed to microplastics, with estimates suggesting that we might inhale around 16.2 bits of plastic every hour—equivalent to 5 grams of plastic every week, which is about the weight of a credit card's worth of plastic in just one week. For the first time in history, microplastic particles have been tracked in the lower airways, raising serious concerns about the potential health impacts.
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Microplastics have been detected in various environments, including the air, water, oceans, lakes, snowfall, and rainfall, according to NOAA researchers. These tiny particles are produced from a wide range of sources, including:

• synthetic materials washed off clothes during laundry cycles, such as polyester and polypropylene
  
• abrasions to vehicle tires or brake components during transportation on the road that cause tiny tire shreds or brake wear particles to fly off
  
• abrasions to everyday plastic or synthetic objects, like the soles of shoes and cooking utensils
  
• runoff from plastic components used to develop and mark roads
  
• coatings used on marine equipment and infrastructure, such as container ships
  
• plastic components used in personal care products, such as plastic microdermabrasion beads in face wash
  
• plastic pellets used in manufacturing

Additionally, microplastics are a byproduct of sewage treatment, where wastewater containing these particles is released into the ocean and then evaporates into the atmosphere in large volumes.

The presence of microplastics in the air is particularly concerning. Microplastics may be present in 4-77% of the air you breathe on a regular basis. Studies have found that microplastics, especially synthetic fibers from textiles, can range in size from 1 to 5 microns—small enough to enter the respiratory system, pass through the lungs, and potentially enter the bloodstream. These particles can damage the air sacs in the lungs, increasing the risk of conditions like emphysema and lung cancer.

A 2020 study in Environment International conducted in London found that the air samples collected from the top of a 9-story building contained between 575 to 1008 microplastics per square meter. The study also suggested that microplastics could travel great distances through wind and weather patterns, potentially reaching remote areas like the North Atlantic and the Arctic during certain seasonal conditions like the North Atlantic Oscillation (NAO).

This growing body of research underscores the pervasive nature of microplastic pollution and the urgent need for further studies to understand the full extent of their impact on human health and the environment.

Accumulation of plastic

Over time, the exposure to plastic really adds up. According to the World Wildlife Federation’s calculations, each month, you consume about 21 grams, or the equivalent of one Lego brick. In a year’s time, you’ve consumed 250 grams, or the size of a full dinner plate’s-worth of plastic.

In 10 years, you’ve ingested some 5.5 pounds, and in the average lifetime, a person will consume about 40 pounds. While much of this will pass through and be eliminated through your stool, some will remain and accumulate in your organs.

Weathered plastic is worse

Recent research has uncovered alarming insights into the effects of weathered microplastics on human health, particularly concerning brain cells. Unlike newly manufactured plastics, weathered microplastics—those degraded by environmental factors such as heat and light—have been shown to trigger a more severe inflammatory response in human brain cells.

In an experiment led by Hee-Yeon Kim and colleagues at the Daegu Gyeongbuk Institute of Science and Technology (DGIST), researchers exposed microglia, the brain's immune cells, to weathered polystyrene microplastics. These plastics, which had undergone environmental degradation, caused a dramatic increase in inflammatory particles in the blood of mice. Additionally, there was a marked increase in brain cell death compared to those exposed to "virgin" or new microplastics.

The study found that weathered microplastics altered the expression (by a factor of 10-15) of proteins involved in energy metabolism and significantly increased proteins associated with brain cell death by a factor of five. The team suggests that these effects might be due to changes microplastics undergo when exposed to sunlight and UV radiation, such as increased brittleness and fragmentation, leading to a larger surface area and altered chemical bonds that heighten their reactivity.

This all amounts to an increased inflammatory response by brain cells — far more severe than what was produced by unweathered microplastics tested at equivalent doses.

This discovery has significant implications for human health, especially considering that much of the microplastic we consume comes from food sources. As plastic waste in the oceans breaks down into microplastics through exposure to sunlight, these particles are ingested by marine life, which then enters the human food chain. The increased neurotoxic potential of weathered microplastics emphasizes the urgent need for further research and potential policy interventions to mitigate the impact of microplastics on human health.

​Accumulation of Lipids and Atherosclerosis: The Role of Nanoplastics

Recent research has highlighted the alarming effects of polystyrene nanoplastics (PS NPs) on cardiovascular health, specifically in the context of lipid accumulation and atherosclerosis. The study demonstrated that exposure to PS NPs, especially when combined with oxidized low-density lipoprotein (ox-LDL), led to significant lipid buildup in RAW264.7 macrophages. This lipid accumulation is a key marker in the development of atherosclerosis, a condition characterized by the hardening and narrowing of arteries due to plaque formation.

Using ultrasound biomicroscopy (UBM), researchers observed the development of atherosclerotic plaques in the aortic arch of ApoE-/- mice after three months of PS NPs exposure. This was further confirmed by Oil-red O and hematoxylin-eosin (H&E) staining, which revealed lipid deposition and plaque formation in the aortic root of these mice.

The study also linked the development of atherosclerosis in these mice to disturbances in lipid metabolism and oxidative stress damage in the liver. This suggests that PS NPs exposure not only affects local cardiovascular structures but also has systemic implications, disrupting lipid regulation and promoting inflammation.
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These findings underscore the potential cardiovascular risks posed by nanoplastic exposure. Atherosclerosis, closely associated with abnormal lipid metabolism and oxidative stress, is a significant contributor to heart disease. The study indicates that PS NPs might exacerbate these processes, raising concerns about their long-term impact on cardiovascular health.

​Microplastics and Heart Disease: A Startling Connection

Independent of the study above, another recent study has brought to light a potentially deadly link between microplastics and cardiovascular disease. Researchers found that individuals with detectable levels of microplastics and nanoplastics (MNPs) in their atheroma—a build-up of plaque in the arteries—had a significantly higher risk of severe health outcomes. Specifically, these individuals had a 353% higher risk of death after 34 months compared to those without detected microplastics. Additionally, patients with carotid artery plaque containing MNPs had a much higher risk of myocardial infarction (heart attack), stroke, or death from any cause within the same timeframe.

In this study, polyethylene—a common type of plastic—was detected in the carotid artery plaques of 58.4% of patients, while 12.1% also had measurable amounts of polyvinyl chloride (PVC). Electron microscopy revealed these microplastic particles within the plaque, showing jagged edges embedded among the plaque's macrophages and scattered debris.
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Correlation or Causation?
While these findings are alarming, it’s crucial to approach them with caution. The study raises important questions but does not definitively prove that microplastics cause heart disease. The presence of microplastics in arterial plaque may be a symptom rather than a cause—patients with higher levels of atherosclerosis might simply have more opportunities for microplastics to become trapped in their arteries. While there is a high likelihood that micro- and nanoplastics cause cardiovascular harm, this study does not prove that finding. In other words, the correlation observed in this study does not necessarily imply causation.

Putting the other known disrupting systemic effects aside, microplastics have been observed directly cause endothelial damage by physically injuring the blood vessel walls, which results in a chronic low-grade inflammation response in said vessels. That low-grade vascular inflammation is a known cause of cardiovascular disease (CVD), dementia, mental conditions, and even cancer. 
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More research is needed to determine whether microplastics directly contribute to the development of cardiovascular disease or whether they are merely coincidental passengers in already-damaged arteries. Nonetheless, the study underscores the urgent need for further investigation into the potential health risks of microplastics.

While the full impact of microplastics on human health is still being understood, the potential risks they pose cannot be ignored. As we continue to unravel the complexities of microplastics and their interactions with our bodies, taking precautionary measures and staying informed will be key to safeguarding our health. Given this caution, there certainly known harms of micro- and nanoplastics as it relates to human health and quality of life, as explored below. 

Cytotoxic: toxic to cells

In a study published in the International Journal of Molecular Sciences, researchers uncovered the cytotoxic effects of microplastics on human cells. The study demonstrated that microplastic particles are capable of entering cells within just 24 hours of exposure, where they predominantly accumulate around the cell nucleus. This rapid infiltration is concerning, as it directly impacts cell health. The study showed that as the concentration of microplastics and the duration of exposure increased, cell viability—meaning the ability of cells to survive—significantly decreased.

Additionally, the study observed alarming changes in immune response markers. Notably, the expression of tumor necrosis factor (TNF-a), a cytokine involved in inflammation, was found to be twice as high in the livers of mice exposed to microplastics compared to those that were not exposed. This suggests that microplastics not only harm individual cells but can also trigger broader immune responses, potentially leading to inflammation and other related health issues.

These findings add to the growing body of evidence that microplastics pose serious health risks, emphasizing the need for further research and public awareness regarding their pervasive presence in our environment and food supply.

Liver Inflammation and Disrupted Metabolism

Micro- and nanoplastics have been shown to cause liver inflammation, a critical concern as the liver is essential for detoxifying the body. These plastics disrupt mitochondrial membrane potential, which is stronger with 5 μm particles, inhibiting ATP production—a crucial energy source for cells. Additionally, MNPs negatively affect food absorption and digestion, leading to altered hepatic lipid metabolism. This can result in changes in cholesterol and triglyceride (serum and total cholesterol, serum and total triglycerides, HDL and LDL) levels, which are risk factors for cardiovascular diseases.

Impaired Gut Health

MNPs can severely affect the gastrointestinal system. They negatively affect food absorption, inhibit food digestion, decrease mucus secretion in the intestine and impair gut microbiota composition, essential for a healthy digestive system. The dysfunction of the intestinal barrier caused by MNPs can lead to gut dysbiosis and impaired bile acid metabolism, further contributing to digestive issues and metabolic disorders.

Neurological Impacts

Nanoplastics, due to their tiny size (the smaller the more harmful), pose a significant threat to the brain. These particles can cross the blood-brain barrier (BBB) within just two hours, a crucial defense that protects the brain from harmful substances. Once they breach the BBB, they can lead to cognitive impairment, neurological disorders, and neurotoxicity. This neurotoxic effect is thought to be due to the inhibition of acetylcholinesterase activity and altered neurotransmitter levels, which can contribute to behavioral changes. The high surface area to volume ratio of these particles makes them particularly reactive and potentially more harmful than larger microplastics.

​Experimental studies have shown that MNPs absorbed into cholesterol molecules on the brain membrane surface can cross the BBB and increase the risk of inflammation and neurological disorders. This could potentially contribute to neurodegenerative diseases such as Alzheimer’s and Parkinson’s. The plastic microparticles in the brain could induce neuroinflammation, leading to long-term damage and chronic neurological conditions.

​In a study published in the August 2023 issue of the International Journal of Molecular Sciences, researchers uncovered alarming evidence that microplastics extensively infiltrate the body, including the brain, and can induce behavioral changes reminiscent of dementia in as little as three weeks. This research involved exposing both young (4-month-old) and old (21-month-old) mice to varying levels of microplastics in their drinking water over a three-week period.

Behavioral testing at the conclusion of the study revealed that many of the mice exhibited dementia-like symptoms, with older animals showing more pronounced changes. The researchers theorized that age-related dysfunction might exacerbate the effects of polystyrene microplastics (PS-MPs) on behavioral performance. Lead researcher Jaime Ross described the findings as "striking" because the doses of microplastics administered were relatively low.

Upon dissecting the animals, the researchers discovered that microplastics had accumulated in every organ, including the brain, which was an unexpected and shocking finding. Although the presence of microplastics in the gastrointestinal tract, liver, and kidneys was anticipated, their expansion to other tissues, such as the heart and lungs, suggests that microplastics are capable of undergoing systemic circulation.

Of particular concern was the detection of microplastics in the brain, which should be protected by the blood-brain barrier, a mechanism designed to prevent harmful substances, including bacteria and viruses, from entering the brain. The presence of microplastics in brain tissue raises significant concerns, as it may lead to a decrease in glial fibrillary acidic protein (GFAP), a protein that supports cell processes in the brain. A reduction in GFAP has been associated with the early stages of neurodegenerative diseases, such as Alzheimer's disease, and even depression.

The study further explained that GFAP is commonly used as a marker for neuroinflammation and is typically found in mature astrocytes, which are cells located in the brain and spinal cord, and is involved in cellular processes such as autophagy, neurotransmitter uptake and astrocyte development. Although inflammation is usually linked to increased GFAP levels, the researchers observed a slight decrease in GFAP expression in the microplastic-exposed mice. This finding aligns with previous studies suggesting that early stages of certain diseases might be characterized by astrocyte atrophy, leading to decreased GFAP expression.
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These findings underscore the potential for microplastics to contribute to neurological damage and cognitive decline, emphasizing the need for further research to fully understand the implications for human health.

Endocrine Disruptors

Microplastics, increasingly recognized as endocrine disruptors, are now believed to be present in the majority of people. These tiny particles can cause structural changes and physical damage in the body, potentially long before their long-term endocrine effects have a chance to accumulate and cause harm on their own. One of the most concerning impacts of microplastics is their potential role in male infertility.
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Many products, particularly canned and plastic goods, are high in synthetic forms of estrogen, such as bisphenol A (BPA). BPA, a well-known xenoestrogen, is notorious for leaching from polycarbonate plastics into food and drinks, especially when exposed to heat. This exposure can lead to various health issues, including alterations in liver function, insulin resistance, damage to developing fetuses, and modifications in reproductive and neurological functions.

Environmental toxins, including microplastics, are capable of penetrating the testicle and semen, potentially leading to deleterious effects on testicular function. This includes impairing testosterone production and sperm production, both of which are critical for male and female fertility. Research indicates that male factor infertility contributes to 50% of all infertility cases and is the sole cause in 20-30% of cases. The presence of microplastics and other endocrine-disrupting chemicals in the environment is increasingly seen as a significant factor in this rising trend.

Moreover, BPA and similar chemicals act as agonists for estrogen receptors, inhibiting thyroid hormone-mediated transcription, altering pancreatic beta cell function, and increasing the likelihood of obesity, cardiovascular diseases, and reproductive issues. The pervasive nature of these toxins in Western civilization underscores the urgent need to address their impact on human health, particularly concerning male fertility and overall endocrine function.
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This segment highlights the pressing concern that environmental pollutants like microplastics pose to human health, particularly through their role as endocrine disruptors and their potential contribution to the growing issue of male infertility.

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influence on cancer

Research has increasingly shown that these tiny plastic particles can induce severe biological effects that span multiple generations and trigger various health conditions, including cancer.

In vitro studies have demonstrated that polystyrene nanoparticles (PS NPs) can induce oxidative stress, which leads to cellular damage in a context-dependent manner. This oxidative stress can result in apoptosis (programmed cell death) and autophagic cell death, processes that can significantly impact the health of exposed organisms.

Research using zebrafish models has provided alarming insights into the long-term effects of PS exposure. Zebrafish injected with 20 nm-sized PS particles during their embryonic stage and later grown in a plastic-free environment still passed on significant health issues to their offspring. The affected offspring exhibited malformations, decreased survival rates, increased heart and blood flow rates, and impaired growth, including smaller eye size and reduced locomotor activity. These effects were linked to increased cell death, elevated reactive oxygen species, and decreased lipid accumulation in the larvae. This study highlights the potential for PS exposure to disrupt biological processes across generations and contribute to disease development, including cancer.

BPA, an endocrine-disrupting chemical widely used in plastic manufacturing, has been identified as a possible risk factor for developing breast cancer. BPA has a strong affinity for non-classical membrane estrogen receptors, such as G protein-coupled receptors (GPER), and can alter multiple molecular pathways within cells (estrogen-related receptor gamma (ERRγ) pathway, HOXB9 (homeobox-containing gene) pathway, bone morphogenetic protein 2 (BMP2) and (BMP4), immunoregulatory cytokine disturbance in the mammary gland). These changes include disruptions in the EGFR-STAT3 pathway, FOXA1 in estrogen receptor-negative breast cancer cells, and epigenetic modifications through the enhancer of zeste homolog 2 (EZH2). These molecular alterations can lead to the undesired stimulation or repression of genes, increasing the risk of developing breast cancer.

The evidence linking MNP exposure to significant health risks is growing. From inducing oxidative stress and cell death to potentially triggering transgenerational effects and increasing the risk of breast cancer, the implications of MNP exposure are profound. Limiting exposure to these harmful particles, especially BPA, is crucial in reducing the risk of developing serious health conditions, including cancer.

Male Reproductive dysfunction

In a groundbreaking study published in IJIR: Your Sexual Medicine Journal, microplastics have been discovered for the first time in human penile tissue. This discovery raises concerns about a potential link between microplastics and erectile dysfunction (ED), opening up new avenues of research into the impact of environmental pollutants on male sexual health.

The study, highlighted by CNN Health, analyzed tissue samples from five men undergoing penile implant surgery for ED at the University of Miami. Astonishingly, four out of the five samples contained microplastics, with polyethylene terephthalate (PET) and polypropylene (PP) being the most common types found.

Ranjith Ramasamy, the study’s lead author and a reproductive urology expert, explained, "The presence of microplastics in the penis is unsurprising. The penis, like the heart, is a highly vascular organ." This observation underscores the potential risk that microplastics pose to vascular-rich organs, but the connection between these particles and ED remains uncertain.

Male infertility remains a global issue, with its causes often not well understood. Given the growing evidence of microplastics infiltrating various biological systems, such as blood and lungs, researchers are now exploring their potential effects on reproductive systems. Previous research has investigated the presence of microplastics in male reproductive organs. For example, in one study, researchers discovered 12 different types of microplastics in the testicles of dogs and humans. In dogs, they found that higher levels of certain microplastics correlated with lower sperm counts and reduced testis weight.

Further research is essential to determine whether microplastics contribute to ED or other health issues. According to Ramasamy, "We need to identify if microplastics are linked to ED and if there are specific types or quantities that cause harm." The discovery marks the beginning of what could be a critical exploration into how microplastics may affect male sexual function and overall health.
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As the scientific community continues to investigate, this study highlights the growing concern over the pervasive presence of microplastics in the human body and their potential implications for health, particularly in sensitive and vital tissues such as those involved in sexual function.

Challenges and pitfalls in micro- and nanoplastic research

The study of microplastics and nanoplastics is fraught with challenges and complexities that make it difficult to fully understand their impact on the environment and human health. One of the main obstacles is the sheer diversity and complexity of these plastic particles. Micro- and nanoplastics are not a single type of material but rather a complex mixture of various polymers, additives, and contaminants. This diversity complicates efforts to develop standardized methods for detecting and analyzing these particles.

Established analytical methods are often not well-suited to handle the complexity of micro- and nanoplastics. For instance, while polystyrene (PS) is commonly used in toxicological studies due to its density, which allows it to easily suspend in water for lab tests, it may not accurately represent environmental microplastics. Polystyrene’s ease of use in creating precisely sized particles and attaching molecules like fluorescent dyes makes it a popular choice for research. However, this very convenience introduces potential pitfalls. The fluorescent dyes used to track these particles can sometimes leak during studies, leading to false or misleading results. Moreover, many studies fail to include necessary controls to account for dye leachate or cellular autofluorescence, further complicating the interpretation of results.

One of the biggest challenges in the field is the lack of harmonized and structured methodological recommendations. Different studies often use different techniques and standards, making it difficult to compare results or draw broad conclusions. Without standardized methods, it's challenging to develop a clear picture of how micro- and nanoplastics behave in the environment and how they impact organisms, including humans.

Another significant issue is the difference between pristine and aged microplastics. Most toxicological studies use pristine, or "new," plastic particles, which do not accurately reflect the state of plastics found in the environment. In reality, environmental plastics undergo aging processes such as weathering, UV exposure, and interaction with chemicals, which can alter their physical and chemical properties. Aged plastics may have different toxicological effects compared to pristine plastics, but this aspect is often overlooked in research.

Adding to the complexity is the fact that there is currently no legal definition or regulation of microplastics in the food chain. While studies have shown that microplastics can enter the food supply, there is no consistent framework for monitoring or limiting their presence in food products. This lack of regulation hampers efforts to assess and mitigate the risks associated with microplastics.
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In summary, the study of micro- and nanoplastics is hindered by the complexity of these materials, inadequacies in current analytical methods, a lack of standardized research protocols, and the challenges posed by the differences between pristine and aged plastics. Moreover, the absence of legal definitions and regulations further complicates efforts to understand and address the risks posed by these pervasive pollutants. Addressing these challenges will require coordinated efforts to develop better research tools, establish clear standards, and create regulatory frameworks that can protect both the environment and public health.

Overview of recyclable plastics and safety profiles

To minimize your contribution to global microplastics pollution, it's essential to make conscious decisions about the plastic products you buy and how you dispose of them. The pervasive issue of microplastics begins with the widespread use of cheap, disposable plastic items that are used once and immediately discarded. With nearly 8 billion people on the planet, this behavior results in an immense amount of plastic waste being generated every day. 
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One of the most effective steps you can take is to choose recyclable plastic goods and recycle them correctly. Look for the universal recycling logo, often marked with a number inside the symbol. With approximately 299 million tons of plastic produced annually, these codes help identify how safe the plastic is, its environmental impact, and its recyclability. This number, known as the resin identification code, identifies the type of plastic and its recyclability. Here's a breakdown of common plastics and how to handle them:

• Polyethylene Terephthalate (PET, Plastic #1): Found in clear beverage bottles, synthetic fibers, and food packaging. PET is recyclable but should not be reused, especially if exposed to heat, as it can leach harmful chemicals, like antimony trioxide and DEHA, to leach into your liquids. Avoid reusing these containers as their porous nature can harbor bacteria.
• High-Density Polyethylene (HDPE, Plastic #2): Used in milk jugs, detergent bottles, and piping. HDPE is opaque, widely recyclable and considered one of the safer plastics. It has a low risk of leaching harmful substances and is widely accepted by recycling programs.
• Polyvinyl Chloride (PVC, Plastic #3): Common in plumbing pipes, cable insulation, medical tubing, and window frames, PVC is not recyclable and should be avoided, particularly for food-related use due to its harmful chemical (phthalates, dioxins, etc.) content which interfere with hormonal development.
• Low-Density Polyethylene (LDPE, Plastic #4): Found in grocery bags, containers, squeezable bottles and some food wraps, LDPE is difficult to recycle. It's better to reuse these items or switch to alternatives like reusable bags. Significant environmental impact.
• Polypropylene (PP, Plastic #5): Used in food containers, automotive parts, textiles, and medical devices, and yogurt cups, PP is generally safe and recyclable in many areas.
• Polystyrene (PS, Plastic #6): Used for disposable cutlery, food containers (foam plates/cups), foam packaging (Styrofoam, packing peanuts), and insulation materials, PS is notoriously difficult to recycle and can leach carcinogenic chemicals (styrene), especially when heated. It's best to avoid using PS altogether. It can take hundreds of years to decompose. 
• Other (Plastic #7): This category includes a variety of plastics (new/mixed plastics, LEXAN, etc.) that are often difficult to recycle and may contain harmful chemicals like BPA. Use products in this category with caution. Some are recyclable and some are not.
  • Polycarbonate (PC): Used in eyewear lenses, DVDs, automotive parts, and reusable water bottles. Should generally be avoided, especially in food and drink containers due to their potential to leach harmful chemicals. 
  • Acrylonitrile Butadiene Styrene (ABS): Found in LEGO bricks, automotive parts, and consumer electronics. It's environmental impact due to poor recyclability is concerning.
  • Polyamide (Nylon): Used in textiles, automotive parts, and industrial components.
  • Polytetrafluoroethylene (PTFE): Known as Teflon, used in non-stick cookware, plumbing tape, and industrial applications.
  • Polylactic Acid (PLA): A biodegradable plastic made from renewable resources like corn starch, used in disposable cups, packaging, and 3D printing. It’s still not perfect for high-temperature environments, as it can deform or release lactic acid under heat.

Summary: Which Plastics Are Safe?

• Safe (With Caution): Plastics #2, #4, and #5 are generally considered safer but should still be used with care, especially regarding microwaving.
• Use with Caution: Plastics #1, #3, #6, and #7 carry higher risks and should be avoided when possible, particularly for food and drink purposes.

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While certain plastics may be deemed safer, it's still advisable to minimize plastic use whenever possible. Consider alternatives like glass, metal, or bamboo, which are safer for both your health and the environment. By reducing your reliance on single-use plastics and opting for reusable, durable items, you can play a significant role in decreasing plastic pollution and its impact on the planet.

Solutions

A 2020 review in Earth-Science Reviews identified microplastics in air pollution as potentially the largest contributor to microplastic contamination worldwide, affecting even remote regions like the Arctic and the vast expanses of our oceans. The pervasive nature of microplastics in the atmosphere is alarming, as these particles are not only inhaled but also deposited on land and water surfaces through precipitation, leading to widespread environmental and health impacts.
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However, there are steps individuals can take to mitigate their exposure to microplastics and reduce their environmental footprint:

1. Opt for Compostable or Biodegradable Products: Traditional plastics are made from synthetic materials that can take thousands of years to degrade. Products labeled as compostable or biodegradable are designed to break down more quickly, either by decomposing in the soil or being consumed by microorganisms. Examples of rapidly degrading materials include starch-based polymers, plant-based silvergrass, wood fiber, and coconut fiber.
2. Avoid Harmful Plastic Substitutes: While it's beneficial to reduce single-use plastics, not all alternatives are created equal. For instance, "biodegradable" plastic bottles or bags may still take years to break down and could release harmful chemicals during degradation. Similarly, bamboo products (straws and silverware), though sustainable in small quantities, could become problematic if demand leads to over-harvesting of bamboo forests. Re-used plastic (clothes or shoes made of “recovered” plastic) still keeps plastic in the manufacturing and consumption cycle, leading to further environmental pollution by microplastics
3. Consider Durable, Eco-Friendly Alternatives: Many companies now offer long-lasting alternatives to plastic, such as glass or stainless steel products. Though initially more expensive, these materials do not generate microplastics and can endure years of use. For example, using stainless steel or glass containers instead of plastic can significantly reduce microplastic exposure, especially when heating food or beverages.

Reducing plastic consumption and waste generation is an effective strategy. Simple steps like using reusable shopping bags, using your own coffee mug when getting coffee to go, avoiding plastic-wrapped dry cleaning, ​bringing drinking water from home in glass water bottles instead of buying bottled water, and store foods in glassware or mason jars instead of plastic bags. You can also take your own leftover container to restaurants, which can significantly cut down the amount of plastic that ends up in landfills and oceans, thereby decreasing the microplastic contamination in our food and water. 

​Strategies such as these will help to reduce the amount of plastic that can migrate into your food.  Plastic is all around us and can be extremely difficult to avoid. But if you start looking around, you may find many areas of your life where you can eliminate the use of plastic and replace the it with something inert that won’t harm the environment and your health.

Given that adults may ingest thousands of microplastics annually through water consumption alone, it is advisable to minimize the use of plastic water bottles. Opting for a non-plastic water container, like one made from stainless steel or copper, can significantly reduce this exposure. Additionally, experts recommend avoiding microwaving food in plastic containers or placing them in the dishwasher, as heat can cause more plastic to leach into food, and release into the environment.

These changes, while seemingly small, can collectively make a significant difference in reducing microplastic pollution and protecting both human health and the environment.

In the battle against plastic pollution, both businesses and individuals play crucial roles. One initiative that stands out is the B Corporation movement. B Corporations are businesses committed to reducing global waste and promoting fair hiring and manufacturing practices across their supply chains. These companies actively work to minimize the use of materials that generate microplastics, making them leaders in sustainability. When shopping, look for the B Corporation logo—a "B" encircled—to support companies that adhere to these eco-friendly standards.

On an individual level, protecting yourself from airborne microplastics is becoming increasingly important. Microplastic particles in the air, though often larger than typical pollutants like PM10 and PM2.5, still pose significant health risks. Thankfully, these larger particles are easier to capture with a high-performance air purifier.

​While many air purifiers can only trap smaller pollutants, high-performance models with centrifugal fans are specifically designed to capture even large and heavy microplastics. These purifiers filter out particles as small as 0.003 microns, which is far smaller than the tiniest microplastics.

Consider using a personal air purifier in spaces where microplastics are likely to accumulate, such as bedrooms or workspaces, where they can be emitted from clothing, appliances, and containers. Additionally, a car air purifier can help filter out microplastics from tire and brake wear, which can infiltrate your vehicle's interior, especially in high-traffic areas.

Purchase (Amazon): Air Doctor

By choosing B Corporation products and investing in effective air purification, you can significantly reduce your environmental impact and protect your health from the dangers of microplastic pollution.

Detoxification

​Emerging research suggests that sweating, whether through exercise or sauna use, may play a role in detoxifying the body from accrued microplastics. A 2022 study detected microplastic particles such as polyethylene, PET, and polymers from sportswear in sweat collected after exercise, indicating that perspiration could aid in the elimination of these particles alongside other toxins like pesticides, flame retardants, and bisphenol-A. This adds to a growing body of evidence showing that sweating can facilitate the excretion of heavy metals, petrochemicals, and other pollutants.
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As with other toxins, microparticle content in sweat could indicate efficacy of interventions promoting clearance. Given the increasing prevalence of microplastics in our environment, inducing sweat through regular sauna use or exercise could offer a simple and accessible detoxification method to help reduce the body's burden of microplastics. However, more research is needed to understand the full impact of repeated sweating on microplastic levels in the body. Additionally, regulatory limits specific to nanoplastics in food and drinks could help safeguard public health given the unprecedented exposure uncovered by advanced microscopy techniques. After all, "seeing" the risk is the first step toward safety.

Learn more about detoxification

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