In this article we discuss the topic of microplastics and nanoplastics, their build-up in the brain, and what current science says about removing them.

Recently studies have revealed alarming levels of microplastics and nanoplastics in the human brain. This amount appears to be increasing over time. A study comparing brain samples from 2016 and 2024 found a 50% increase in microplastic concentrations.

While the presence of microplastics in the brain is concerning, researchers are still investigating how these particles might interact with brain cells, and what negative impacts they have. The increase in levels mirrors the growing environmental exposure to these particles.

What are common sources of nanoplastics?

• Clothing: Tiny plastic fibers shed from synthetic fabrics like polyester and nylon during washing.
• Personal care products: Some exfoliating scrubs and cleaners contain microbeads, which can break down into nanoplastics. Sunscreens and toothpastes might also contain nano-sized plastic particles.
  • Crest, Aquafresh, Prodent, Oral-B, and Zendium are all known to contain nanoplastics.
  • Key ingredients in toothpaste to watch out for:
    • Polyethylene (PE)
    • Polymethyl methacrylate (PMMA)
    • Polypropylene (PP)
  • Plastic-free toothpaste options include Bite Toothpaste, Unpaste Tooth Tabs, and Georganics Toothpaste Tablets.
• Industrial processes: Activities like 3D printing, thermal cutting of plastics, and electrospinning can release nanoplastics into the environment.
• Packaging materials: Plastic packaging can degrade into smaller particles over time.
• Marine coatings: Coatings used on ships and marine structures can also contribute to nanoplastic pollution.
• Medical products: Certain biomedical products and drug delivery systems use polymeric nanoparticles.
  • Cancer therapy: Polymeric nanoparticles are used to delivery chemotherapy drugs directly to tumor cells.
  • Gene delivery: These nanoparticles can be used to deliver genetic material into cells for gene therapy applications
  • Wound healing: Polymeric nanoparticles can be incorporated into dressings to promote healing.
  • Ocular drug delivery: These nanoparticles are used to delivery drugs to the eye for treating conditions like glaucoma.
  • Antibiotic delivery: Polymeric nanoparticles can be used to deliver antibiotics to infection sites.
  • Diagnostic agents: Nanoparticles can carry imaging agents for diagnostic purposes,s cuh as in MRI or CT scans.
  • Nutraceuticals: Nano particles are used to deliver vitamins, minerals, and other nutrients in a controlled manner.
• Tire wear: Abrasion of vehicle tires contributes micro- and nanoplastic particles to the environment.
• Food and water: Contaminated drinking water, seafood, table salt, and beverages like tea (from plastic teabags) are common ingestion pathways. Both fresh and marine water bodies can accumulate nanoplastics from the breakdown of larger plastics and from runoff containing urban and industrial waste.
• Soil and agricultural sources: Plastics used in agriculture contribute to soil contamination, which can transfer to plants consumed by humans.
• Printed materials: Synthetic polymers used in printing on everyday items can degrade into nanoplastics.
• Glitter: These contribute to environmental pollution and break down further into nanoplastics.

These nanoplastics can enter our bodies through ingestion (food and drinks), inhalation (airborne particles), and skin contact (dermal absorption from cosmetic products). Once inside the body, nanoplastics can cross biological barriers (intestinal, blood-brain, placental) and accumulate in organs, potentially causing oxidative stress, inflammation, and other health issues.

Removing microplastic from the body

The brain’s glymphatic system is responsible for clearing waste products. Stimulating this system might help remove nanoparticles. Ways to stimulate the glymphatic system include getting enough sleep and exercising.

Nanoparticles can induce oxidative stress. Antioxidants like glutathione, vitamin C, omega-3s, or N-acetylcysteine (NAC) might mitigate damage and support cellular repair.

Microplastics are synthetic polymers, such as polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET), which are highly resistant to degradation. However, certain naturally occurring enzymes in the brain and other parts of the body might have the potential to break down microplastics, either directly or indirectly.

• Lipases and Esterases
  • These enzymes break down ester bonds, which are present in some types of microplastics like PET.
  • Lipase: Found in various tissues, including the brain, lipases can hydrolyze ester bonds in fatty acids and potentially in certain polymers.
  • Increasing lipase: Consuming a diet rich in healthy fats, such as omega-3 fatty acids found in fish, nuts, and seeds.
  • Esterase: Can degrade ester-containing polymers, though its activity on synthetic plastics is limited.
  • Increasing esterase: Consuming foods rich in choline, such as eggs, liver, soybeans, and cruciferous vegetables.
• Proteases break down peptide bonds in proteins but might also have some activity on synthetic polymers with similar chemical structures.
  • Matrix Metalloproteinases (MMPs): These enzymes are present in the brain and are involved in extracellular matrix remodeling.
  • Increasing proteases such as MMPs: Consuming foods rich in antioxidants and anti-inflammatory compounds such as fruits, vegetables, and omega-3 fatty acids. Certain supplements, such as vitamin C, vitamin E, and other antioxidants may support MMP activity.
• Oxidoreductases
  • These enzymes catalyze oxidation-reduction reactions and could potentially degrade polymers by breaking down their carbon-carbon bonds.
  • Cytochrome P450: Found in the brain and liver, these enzymes oxidize a wide range of substrates.
  • Peroxidases: Use hydrogen peroxide to oxidize substrates and could potentially degrade polymers.
  • Increasing oxidoreductases: Fruits, vegetables, nuts, and seeds. Supplements such as N-acetylcysteine (NAC), alpha-lipoic acid, and Coenzyme Q10.
• Hydrolases break down chemical bonds through hydrolysis, which could be relevant for degrading certain types of microplastics.
  • Amylase: Might have some activity on polymers with similar glycosidic bonds as starch.
  • Cutinase: Although not naturally occurring in the brain, this enzyme has been shown to degrade PET.
  • Increasing hydrolases: Potatoes and grains, as well as digestive enzyme supplements that contain amylase and other hydrolases.

Other foods and supplements to increase overall brain enzyme activity: Berries, dark leafy greens, fatty fish (salmon, mackerel), flaxseeds, chia seeds, walnuts, eggs, lean meats, legumes, dairy products, fortified cereals, B6, B9, B12, curcumin, and resveratrol.

The gut microbiome produces enzymes that can break down various compounds. Supporting gut health may indirectly influence brain health. Examples include fermented foods like yogurt, kefir, and sauerkraut, and probiotic supplements.

Chronic stress can impair enzyme function, so practices like meditation and mindfulness may help.

Challenges to enzymes:

• The Blood-Brain-Barrier limits the entry of enzymes or microbial agents that could degrade microplastics.
• Even if enzymes break down microplastics, the resulting monomers or oligomers could be toxic to brain cells.

Natural detoxification methods

• Cellular support
  • Phospholipid supplements: Phospholipids, key components of cell membranes, can trap fat-soluble toxins (including microplastics) into droplets that are eventually expelled from the body.
  • Liver support: Supplements like liposomal glutathione can enhance liver function, a critical organ for detoxification.
• Blood donation: Regular blood donation may reduce the level of microplastics in the bloodstream by allowing the body to regenerate new blood cells.
• Increase fiber intake: Consuming high-fiber foods like fruits, vegetables, and nuts can promote gastrointestinal health and help expel toxins, including microplastics, through regular bowel movements.
• Hydration: Drinking plenty of water supports kidney function and helps flush out water-soluble toxins.
• Sweating: Engaging in physical activities or using saunas can stimulate sweating, which may assist in eliminating certain toxins like bisphenol A (BPA), often associated with plastics

Removing microplastic from the environment

There are enzymes that show promising results in breaking down microplastics, for example in water treatment facilities. However, most of these enzymes are not safe for human ingestion.

• Enzymes from microorganisms (bacteria and fungi) have shown promise in breaking down microplastics.
  • PETase: Discovered in Ideonella sakaiensis, this enzyme specifically degrades PET.
  • MHETase: Works in tandem with PETase to further break down PET into its monomers.
  • Laccase: A fungal enzyme that oxidizes a wide range of substrates, including synthetic polymers.
  • Various cutinases from bacteria like Thermobifida fusca and Thermobifida cellulosilytica can degrade PET, with some engineered versions showing enhanced activity.
  • Bacterial lipases from species like Bacillus and Pseudomonas have been recognized for their ability to break down plastic polymers like polyurethane and PET oligomers.
  • Enzymes like manganese peroxidase and lignin peroxidase, primarily from fungi such as Phanerochaete chrysosporium and Trametes versicolor, have shown capability in degrading PE by breaking carbon-carbon bonds.
  • Alkane Hydrolases found in bacteria like Pseudomonas have potential in initiating the degradation of PE by creating more reactive sites on the polymer.
  • Studies have identified enzymes from strains like Comamonas testosteroni in sewage sludge, which can break down PET into its monomers.
  • Fungi like Aspergillus flavus and Trichoderma harzianum have been noted for producing enzymes such as laccase and peroxidase that can degrade high-density polyethylene (HDPE) microplastics.

Prevention of further exposure

• Avoid processed foods: Processed and packaged foods are more likely to contain microplastics. Opting for organic and fresh foods can reduce ingestion.
• Filter water: Using advanced filtration systems can remove a significant percentage of microplastics before consumption.
• Reduce plastic use: Minimizing contact with plastic packaging and containers reduces exposure to microplastic particles and associated chemicals.
• Avoid cosmetics with microbeads or polymers.
• Regular cleaning can reduce dust, which might contain microplastics from synthetic fibers.

Last updated Feb 11, 2025.