Microplastics: The Unseen Threat to Health and Environment
Microplastics, defined as tiny particles smaller than 5 mm, have infiltrated every corner of our natural world — from the depths of the oceans to the peaks of the highest mountains. Their widespread presence in bottled water, our food (including fresh fish), and even the air we breathe highlights an urgent need for awareness and action.
The Ubiquity of Microplastics in Our Environment
— Microplastics in Air, Water, and Soil
Microplastics have become pervasive in our environment, contaminating air, water, and soil systems worldwide. Research indicates that terrestrial microplastic pollution is significantly more prevalent than marine pollution. Depending on the environment, estimates suggest it is four to twenty-three times greater on land than in the ocean.
Alarmingly, one-third of all plastic waste ends up in soils or freshwater, breaking down into microplastics and eventually into nanoparticles. These particles have even been detected in tap water, carrying harmful organisms, and posing a threat to public health and environmental safety.
Plastic breaking down into microplastic in the sea
— The Impact on Ecosystems
The effects of microplastics on ecosystems are profound and multifaceted. In soil, microplastics interact with soil fauna, altering their behaviour and physiological processes. For example, earthworms change their burrowing patterns in the presence of microplastics, negatively impacting soil conditions, which can harm crop yield and biodiversity.
Additionally, microplastics in soil lead to a decline in below-surface species, such as mites and larvae, which are essential for maintaining land fertility. Chemical components like chlorinated plastics leach harmful substances into the soil and water, disrupting ecosystems and threatening species that rely on these resources.
In marine environments, microplastics accumulate in sediments and coastal areas, where they are ingested by various marine organisms, from large mammals to small molluscs. This contamination affects their health, feeding patterns, and reproduction. Furthermore, microplastics can act as carriers for other pollutants like heavy metals and hydrophobic organic chemicals, amplifying their detrimental effects on aquatic life and potentially entering the human food chain.
Pathways of Human Exposure to Microplastics
— Food and Water Contamination
We are increasingly exposed to microplastics through our food and water. Significant concentrations of microplastics have been found in commonly consumed marine species, such as Atlantic cod and European hake. This contamination extends to freshwater sources, where materials like polyethylene (PE) and polypropylene (PP) constitute over 90% of the microplastics found in drinking water.
The World Health Organization (WHO) reports an average microplastic content of about five particles per litre in tap water. Alarmingly, bottled water drinkers are at an even higher risk, ingesting an additional 90,000 microplastic particles annually compared to the 4,000 ingested from tap water alone.
Even everyday activities, such as using tap water to brew tea, introduce more microplastics into our consumption. Research has shown that tea bags can release millions of microplastic particles into the drink, amplifying exposure.
Tea bags, a truly underestimated source of microplastics
— Airborne Microplastics
Airborne microplastics represent another significant pathway of exposure. Both indoor and outdoor air is contaminated by microplastics from various sources, including synthetic fibres from textiles, building materials, and by-products of waste incineration. Once inhaled, these particles can settle in the lungs, and some have been detected in human lung tissue, raising concerns about their ability to bypass our respiratory defences.
People working in industries such as synthetic fibre manufacturing are at an even greater risk of exposure, increasing the likelihood of respiratory and lung diseases.
— Direct Contact with Microplastics
Direct contact with products containing microplastics is a common, yet often overlooked, exposure pathway. Everyday items — like plastic packaging, cling film, textiles, and personal hygiene products — all shed microplastics. Moreover, activities like handling decomposing fishing nets or being in environments with deteriorating paint fragments contribute to direct microplastic exposure.
Over time, these particles accumulate in the body, potentially triggering immune responses or causing localised toxicity.
Microplastics in Marine Life and Our Food Chain:
Microplastics consumed by marine organisms often bioaccumulate as they move up the food chain. For instance, smaller fish ingest microplastics, and these fish are then eaten by larger predators, concentrating the amount of microplastics in the latter. When humans consume seafood, particularly species at the top of the food chain like tuna or salmon, we may be ingesting a higher concentration of these toxic particles. This phenomenon, known as biomagnification, raises significant health concerns as it compounds the risk of microplastic exposure.
Microplastics and the so-called Climate Crisis:
The production and degradation of plastics are linked to greenhouse gas emissions. Plastics are derived from fossil fuels, and their production emits significant amounts of polluting compounds.
When plastics break down into microplastics, they release methane and ethylene, potent greenhouse gases, especially when exposed to sunlight.
Legislation and Policy to Combat Microplastics
Governments and international bodies are beginning to recognise the severe impact of microplastics on human health and ecosystems. Policies aimed at banning single-use plastics, improving waste management, and regulating plastic production are emerging. However, it is too little too late, and no one is ever accountable when money reigns.
The European Union, for instance, introduced restrictions on microbeads in cosmetics in 2018, with other countries following suit. Additionally, the UK government has introduced initiatives aimed at reducing plastic waste, such as banning plastic straws and stirrers. However, experts argue that stricter global measures are needed to address microplastic pollution on a larger scale.
Microplastics and the Future of Health:
As research into the long-term effects of microplastic exposure is still in its infancy, future health outcomes could reveal even more alarming consequences. Potential links between microplastics and neurodegenerative diseases, including Alzheimer’s and Parkinson’s, are being explored, as microplastics may have the capacity to cross the blood-brain barrier. As new studies emerge, the public health implications of microplastic contamination may necessitate not only personal behaviour changes but also widespread societal and industrial reform.
Health Risks Associated with Microplastics
— Physical and Chemical Toxicity
Microplastics pose more than just physical threats — they can also carry harmful environmental toxins. These include bisphenol A (BPA), which disrupts endocrine and reproductive systems. Microplastics can migrate into human tissues, affecting vital organs such as the liver, kidneys, arteries, and brain. This interaction can alter metabolic pathways and exacerbate pre-existing health conditions.
Moreover, microplastics can form a protein “corona” — a structure that increases their toxicity when combined with external pollutants, leading to even greater health risks.
— Inflammatory Responses
Inside the human body, microplastics trigger immune responses. Once ingested by cells, they disrupt intracellular signalling and immune homeostasis, causing tissue and organ damage. Immune cells, such as cytokines, release inflammatory molecules, potentially worsening conditions like ulcerative colitis and Crohn's disease.
Microplastic exposure has also been linked to the production of reactive oxygen species, which contribute to oxidative stress and inflammation, known risk factors for several diseases.
Long-term Health Effects
The long-term health implications of microplastic exposure are alarming. Continuous exposure may lead to chronic respiratory inflammation, interstitial pneumonia, and even chronic obstructive pulmonary disease (COPD). Research has shown that microplastics in human blood significantly increase the risk of heart attacks, strokes, and other cardiovascular diseases.
Understanding the complex interactions between microplastics, genetic factors, and overall health is crucial for developing strategies to mitigate these risks.
Personal Actions to Reduce Microplastic
— Exposure
Reducing your exposure to microplastics begins with simple lifestyle changes:
Opt for clothing made from natural fibres instead of synthetic materials to reduce the release of microplastics during laundry.
Use the spinning setting on your washing machine to a maximum speed of 800, instead of 1200 or 1400, to minimise the levels of microplastics entering the water system.
Use glass or stainless-steel containers instead of plastic and minimise your reliance on single-use plastics.
Install home water filtration systems to reduce microplastic ingestion, especially if you primarily drink tap water.
Regularly clean living spaces to minimise the build-up of microplastic dust indoors.
Additional Steps for a Healthier Lifestyle
Incorporating certain foods and habits into your lifestyle can help counteract the negative effects of microplastics:
Eat a diet rich in cruciferous vegetables, leafy greens, garlic, and ginger, which support detoxification.
Stay hydrated to help your body flush out toxins more effectively.
Engage in lung-regenerative practices, such as deep breathing exercises, to reduce airborne microplastic accumulation in the respiratory system.
Frequently Asked Questions
What are the negative health impacts of microplastics?
Microplastics can cause several harmful effects on human health, including oxidative stress, metabolic disorders, immune system reactions, neurotoxicity, and reproductive and developmental issues.
Is it necessary to be concerned about microplastics?
Yes, there is significant cause for concern. Research involving mice has linked microplastics to intestinal inflammation and cognitive decline. In humans, microplastics found in major arteries have been linked to increased risks of heart attacks and strokes.
Can microplastics be removed from the human body?
Microplastics, once ingested and deposited in the body’s tissues and organs, can be naturally flushed out; however, very small particles may remain. However, reducing exposure is the best course of action. It can be done by decreasing the use of plastic products and opting for natural materials instead.
Which demographic is most susceptible to the effects of microplastics?
Babies and children are particularly vulnerable, as they are exposed to higher levels of microplastics from contaminated dust on floors and carpets. This raises concerns about developmental issues and long-term health consequences.
Because infants and children spend more time on the floor and carpets, they are exposed to many times the levels of toxins an adult is exposed to as they breathe contaminated dust — including microplastic, phthalates (additives in the manufacture of plastic), BPA and similar compounds, heavy metals, and many more.