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Microplastics and nanoplastics are emerging contaminants that pose a growing threat to environmental and human health. Defined as plastic particles less than 5 mm in size, microplastics originate from a variety of sources, including industrial waste, cosmetic products and the degradation of larger plastic items. Nanoplastics, even smaller, measure less than 1,000 nanometers and are capable of penetrating biological barriers. While much of the concern surrounding these pollutants has focused on marine ecosystems, their presence in food and beverage packaging – particularly in items perceived as healthy – raises additional alarms. One such example is microplastics and tea bags.

A study conducted by the Mutagenesis Group at the Autonomous University of Barcelona (UAB) has provided compelling evidence that commercial tea bags release vast quantities of micro- and nanoplastics (MNPLs) when infused in hot water. More importantly, this study is the first to demonstrate that these particles can be absorbed by human intestinal cells, potentially entering the bloodstream and dispersing throughout the body.

Microplastics and tea bags: Scope of the problem

What are tea bags made of?

Commercial tea bags are no longer made exclusively from paper. Modern variants often contain synthetic polymers such as:

Nylon-6 : Known for its durability and heat resistance

Polypropylene : A widely used thermoplastic in food-grade packaging

Cellulose : A semi-synthetic material derived from plant fibers, sometimes chemically treated for added strength

These materials, while effective in maintaining the structural integrity of the bag during brewing, contribute to the release of plastic particles under high temperatures and help explain the link between microplastics and tea bags.

Particle release by polymer type

Using hot water to prepare an infusion causes these materials to shed particles at an alarming rate. The UAB study investigated the link between microplastics and tea bags, quantifying the particle release per milliliter (mL) of brewed tea as shown in Table 1.

Table 1. The quantity and average particle size of particles released by each polymer type when brewing tea with tea bags composed of polypropylene, cellulose and nylon-6.

Polymer Type Particle Concentration (particles/mL) Average Particle Size (nm) Polypropylene 1.2 billion 136.7 Cellulose 135 million 244 Nylon-6 8.18 million 138.4

These figures reflect a significant and previously underappreciated source of microplastic exposure for regular tea drinkers, demonstrating a link between microplastics and tea bags.

Credit: iStock.

Analytical techniques for characterizing microplastics

Accurate characterization of MNPLs in complex biological and environmental matrices requires advanced analytical tools. The UAB team employed a suite of complementary techniques to identify a link between microplastics and tea bags and assess the physical and chemical properties of particles released from the tea bags:

Imaging and spectroscopy methods

Scanning electron microscopy : Provided high-resolution surface images of the particles.

Transmission electron microscopy : Offered detailed internal structure visualization at the nanoscale.

Attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR) : Enabled identification of polymer types based on molecular vibrations.

Particle size and charge analysis

Dynamic light scattering : Measured the hydrodynamic size distribution of particles.

Laser Doppler velocimetry : Assessed zeta potential to understand particle surface charge.

Nanoparticle tracking analysis : Tracked individual particles in liquid samples to determine size and concentration.

According to lead researcher Dr. Alba Garcia, “We have managed to innovatively characterise these pollutants with a set of cutting-edge techniques, which is a very important tool to advance research on their possible impacts on human health.”

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Biological interaction with human cells

To evaluate potential health effects from microplastics and tea bags, the team exposed stained MNPLs to various types of cultured human intestinal cells. This experimental approach allowed them to assess cellular uptake and localization of plastic particles.

Key findings

Highest uptake in mucus-producing cells : Among the cell types tested, mucus-secreting intestinal cells internalized the highest volume of MNPLs.

Intracellular localization : Particles were found not only within the cytoplasm but also in the nuclei of cells, raising concerns about possible genetic-level effects.

These results suggest a mechanism through which MNPLs could cross intestinal barriers and gain access to systemic circulation, potentially affecting distant organs over time.

Implications for food safety and human health

The ability of microplastics to interact with and be absorbed by human cells underscores the need for rigorous food safety assessments and regulatory oversight.

While long-term effects are still under investigation, potential health risks could include:

Inflammation and immune response : Chronic exposure may trigger immune dysregulation

Genotoxicity : The presence of plastics in cell nuclei suggests a theoretical risk of DNA damage

Bioaccumulation : Repeated exposure could lead to the accumulation of particles in tissues.

Regulatory gaps

Currently, there are no universally standardized test methods for assessing MNPL contamination in food-contact materials, including microplastics and tea bags. Researchers emphasize the need for:

Standardized testing protocols : To evaluate contamination levels across products

Regulatory frameworks : To establish safe limits and guide manufacturing practices

Public awareness campaigns : To inform consumers about potential risks

“As the use of plastic in food packaging continues to increase, it is vital to address MNPLs contamination to ensure food safety and protect public health,” the study authors state.

Toward a safer future

The study was carried out under the European PlasticHeal project, which aims to understand how MNPLs affect human health and develop tools to mitigate exposure.

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To reduce contamination from microplastics and tea bags, manufacturers could consider:

Alternative materials : Using fully biodegradable and heat-stable natural fibers

Improved manufacturing standards : Limiting the use of thermoplastics in food-contact components

Consumer guidance : Encouraging the use of loose-leaf tea or paper-based bags without plastic reinforcement

The link between microplastics and tea bags presents a tangible route of human exposure to plastic pollution. With the demonstrated ability of these particles to interact with and be absorbed by intestinal cells, concerns over long-term health effects are warranted. By leveraging advanced analytical techniques and promoting regulatory reform, the scientific community can play a pivotal role in safeguarding public health.

Continued research and interdisciplinary collaboration are essential to fully understand the risks posed by MNPLs and to develop effective strategies for minimizing their presence in everyday consumer products.

This article is a rework of a press release issued by the Autonomous University of Barcelona. Material has been edited for length and the content has been updated to provide additional context and details of related developments since the original press release was published on our website. This article includes text that has been generated with the assistance of AI. Technology Networks’ AI policy can be found here.

Sunscreens have become an important part of people’s sun management routine, protecting skin from harmful solar UV radiation. But many of these products contain chemicals that can be harmful to saltwater and freshwater ecosystems, while preliminary findings indicate some ingredients can have health effects.

Ultraviolet filter chemicals and mineral components found in sunscreens can harm marine species such as corals and help trigger bleaching. In recent years, numerous studies have shown that many of these chemicals persist in the environment and can impact seagrass, fish and other marine life.

More research is needed to understand the full environmental and health impacts of chemicals used in sunscreens. New formulations using ingredients proven to be safe are required, say analysts, and makers should improve product labelling to better inform consumers, with government regulation potentially necessary.

Experts also urge caution, noting that while there are environmental concerns surrounding sunscreen chemicals, this should not be understood as a call not to use these products. See All Key Ideas

Today’s beach outing is not the same as your grandparents’ beach outing: With intense summer heat waves now the norm due to climate change, and with the ozone layer still not fully healed, people need more and better sun protection when outdoors.

Sunscreen offers proven protection from sunburn and skin cancer — but it’s also often comprised of a cocktail of ingredients including chemicals that scientists warn are a growing source of environmental pollution.

Much of this concern focuses on a variety of ingredients known as ultraviolet (UV) filters. Sunscreens typically come in two forms: organic (using chemicals to absorb solar radiation), or inorganic (using zinc oxide and titanium oxide to reflect away solar radiation).

An estimated 6,000 to 14,000 metric tons of UV filtering chemicals are released annually into coastal regions with coral reefs. And in recent years, scientific evidence of sunscreen chemicals harming sensitive marine ecosystems has accumulated, resulting in a series of local, regional and national bans of some chemical ingredients to protect living reefs.

Experts now underline that these concerns go far beyond coral reefs.

In a 2025 paper, researchers at Plymouth Marine Laboratory in the U.K. outlined how some sunscreen chemicals impact a host of marine organisms at a molecular, cellular, individual or community level. Studies show that UV filters are linked to effects on enzyme growth, endocrine disruption, reproductive issues and more. UV filters can affect not only coral, but species of seagrass, fish and other marine life.

The researchers are calling for an “urgent investigation” of the wider impacts on marine life. “If there’s a risk that these chemicals can harm coral and other marine life, if there’s less harmful compounds out there that we can use instead, then we need to establish what they are,” says Anneliese Hodge, a Ph.D. student at Plymouth Marine Laboratory and lead author of the 2025 paper. “We need to research that … and figure out the alternatives.”

Experts emphasize that sunscreen ingredients number among the many thousands of other synthetic pollutants that leak into the environment annually, most of which haven’t been tested for safety. Scientists have already assessed that humanity has crossed a “safe operating space” for chemical pollution and release of these “novel entities.”

In addition, there are preliminary findings that some chemicals used in some sunscreens may also impact human health — though those findings are still cloaked in uncertainty due to a lack of long-term ecotoxicological testing. These early findings have given rise to an “anti-sunscreen” movement in the media that experts say must be addressed with caution to avoid misinformation.

Sunscreen’s environmental toll

UV filters are known as a “pseudo-persistent pollutant.” Over time, they will degrade, though some may break down into more toxic forms. However, the speed of degradation is being outpaced by the rapid and consistent rate at which they’re flowing into the environment.

Sunscreen chemicals wash off beachgoers’ or sunbathers’ bodies or enter the environment via wastewater. Many treatment facilities can’t remove them, meaning that potentially vast quantities of wastewater effluent contain UV filters. This pollution load reaches environmentally concerning levels during the Northern Hemisphere’s peak summer holiday season.

It’s not only sunscreens that are responsible; UV filters are present in an array of cosmetics and also released by various industries, says Lenka McGachy, professor of environmental chemistry at the University of Chemistry and Technology, Prague.

This ubiquity makes them a common pollutant in waters across the world, even in far-flung locales like Antarctica.

Numerous studies have outlined the ways in which corals, seagrass, fish and other marine organisms are susceptible to sunscreen chemical ingredients. Studies show they can prompt coral bleaching, impact zooplankton hatching or development rates, and cause impairments to the structure of sea urchin sperm. Other research has found UV filters in species like rainbow trout, threatened loggerhead turtles and dolphins.

But knowledge gaps remain, say experts. A 2025 paper notes “significant or complete data gaps for acute and chronic exposure data” of organic UV filters for freshwater “amphibians, sediment organisms, aquatic fungi and other rarely tested organisms.”

Craig Downs, an ecotoxicologist and executive director of the Haereticus Environmental Laboratory in the U.S., emphasizes that these contaminants are found not only in coastal waters but also in freshwater lakes and streams. “There are multiple axes of toxicities associated with the petrochemical sunscreens,” he says. “Ranging from reproductive development toxicities to neurotoxicity to increased risk for mutagenicity and carcinogenicity and then endocrine disruption.”

A troubling, largely unanalyzed brew

Sunscreen pollution poses a big problem for researchers: It isn’t happening in a vacuum. It exists in the environment alongside a host of other contaminants, and how they all interact remains unknown. “When you have a complex mixture of chemicals, like what you might have at a wastewater effluent site, it can potentially increase the overall impact on the organism,” Hodge says. Sorting out interaction impacts is challenging.

For example, one troublingly recent study found that sunscreen chemicals, including ethylhexyl methoxycinnamate (EHMC), can bind to plastics in the environment and slow their degradation.

“It’s as if [EHMC] acts like a ‘biofilm stabilizer,’ shielding the plastic and its microbial inhabitants from natural degradation processes,” study co-author Sabine Matallana-Surget, a professor of environmental molecular microbiology at the University of Stirling, U.K., wrote in an email. “Plastic already takes up to a century to degrade in the ocean; if it’s covered by stabilizing biofilms triggered by co-pollutants like EHMC, its persistence could be even longer.”

Equally worrying is that this comingling can create a “co-pollution scenario” with the microbial communities that cling to plastic-UV filter surfaces, posing a risk to marine ecosystems and human health. If marine organisms ingest these plastics, they not only face harm from the physical plastic, but also from the chemicals coated and absorbed by it.

There’s still another concern, says Awadhesh Jha, a professor of genetic toxicology and ecotoxicology at University of Plymouth: The bioaccumulation of UV filters and other chemicals in marine species may end up being consumed by people.

An estimated “4.3 billion people are reliant on fish for 15% of their protein intake,” he says. “Safeguarding production of healthy seafood in the changing environment is crucial for the sustainability of aquaculture industries.”

Coral- and reef-safe, or not?

Experts are urging stricter regulation of sunscreen marketing, noting that while some readily available sunscreens branded as “reef-safe” or “coral-safe” don’t contain chemical UV filters, these brands often don’t come with actual evidence of meeting safety goals.

These labels, in some instances, amount to little more than greenwashing, according to experts. Studies suggest that a number of sunscreens branded reef- or coral-safe are “a bit less toxic than the not environmentally friendly sunscreens,” but are still toxic, says Pedro Echeveste De Miguel, a marine microbial ecologist at the University of the Balearic Islands, Spain.

For many products, these claims are made without adequate toxicity testing or proof to validate them. “That’s really concerning. It misleads consumers into thinking that they’re doing the right thing,” Hodge says.

There’s also a need to challenge assumptions and claims that inorganic mineral-based sunscreens are always better for the environment than formulas using organic UV filters. A recent paper found that “coral-friendly” sunscreens containing zinc oxide (a mineral formulation) caused severe impacts to soft and hard corals, as compared to “reef-safe” formulas containing organic UV filters that caused mild or no effects.

“This shows why credible, standardized testing is urgently needed,” says Johanna Leonhardt, director of operations at Soneva Conservation & Sustainability in the Maldives, who was part of the study. She also emphasizes that ecotoxicology testing must not only include individual ingredients, but also full formulation testing, and that companies should fully disclose active filter ingredients.

A sensitive topic

While sunscreens can have real environmental impacts, misinformation is also rife. Social media has recently given rise to an avid anti-sunscreen movement spreading unsubstantiated claims that these products cause a range of diseases, including cancer.

That being said, there are concerns among experts regarding studies finding that chemicals used in sunscreens (such as avobenzone, oxybenzone, octocrylene and ecamsule), when applied to the skin, can enter the bloodstream. Similarly, research suggests inorganic sunscreens containing nanoparticles can get into the blood. But still other studies suggest these chemicals may have no impact and are safe, though more research is needed.

A major health concern for both people and marine life is the potential for endocrine disruption linked to some chemicals. As with the environmental concerns, much of the human health focus has coalesced around two ingredients: oxybenzone and octinoxate.

“This isn’t just about damaging coral. These compounds have the potential to damage health, to cause problems with human health,” says Greg Kearns, associate dean for research at Texas Christian University’s Burnett School of Medicine in the U.S.

“No studies been done to say this amount of this sunscreen and this chemical causes this injury or illness,” Kearns cautions. “But we know the potential exists. And if the potential exists, that begs the question in science, do we need to know more about this? I think the answer is, yes.”

Studies suggest that a range of chemicals — including oxybenzone, ethylhexyl methoxycinnamate (octinoxate) and 4-methylbenzylidene camphor — should be avoided during pregnancy due to their endocrine-disrupting potential. Research published last year found that sunscreen ingredients like phenols and parabens could also increase the risk of hypertension during pregnancy.

In 2021, the U.S. Food and Drug Administration assessed that only zinc oxide and titanium oxide are “generally recognized as safe and effective,” noting that 12 other ingredients didn’t meet FDA criteria due to lack of data. Elsewhere, the EU has placed limits on the use of oxybenzone and homosolate. Recently the Australian government flagged the same chemicals for restrictions due to health concerns.

All these data put users worried about environmental and potential health effects in a tricky spot, especially given that specific ingredients and concentrations are often not listed on product bottles or squeeze tubes.

David Andrews, acting chief science officer at the Environmental Working Group, a research and advocacy nonprofit, says that ultimately it’s not “an all-or-nothing type equation” for sunscreen users. “We know getting sunburned is bad and sunscreen is one of those tools against that,” he says.

His organization suggests using mineral-based sunscreens first as the safest option — both from a health and environmental perspective — but also stresses that, ultimately, decisions on use should be based on what works best for each person.

Others such as Hodge agree that although several studies suggest mineral UV filters may be less acutely harmful than some organic filters, but uncertainties about particle behavior and sub-lethal effects mean further research is required.

“Sometimes the narrative when we discuss sunscreens and its impact on marine life, it quickly … steers towards people thinking that we’re telling them that they can’t wear sunscreen, and that they think it needs to be a choice between harming marine life or getting skin cancer,” she says. “I think it’s important that consumers do know that we’re not telling them to not wear sunscreen.”

Screening your sunscreen

Experts Mongabay spoke to agree that changes are needed in the way sunscreens are made and regulated to better protect people and Earth. Industry and manufacturers also must do much more to ensure and prove the safety of their products.

“We support much needed efforts to do a more comprehensive review of health and environmental concerns,” Andrews says. “That includes substantiating the safety and toxicity of these sunscreens during long-term usage.”

He underlines that this is not a call for people to abandon sunscreen use, but for consumers to educate themselves and scrutinize ingredients, and make use of traditional techniques to manage exposure to the sun. “You don’t want to overly rely on sunscreen,” he notes, stating that appropriate clothing, sun hats and seeking shade are important in sun protection.

Downs, from the Haereticus lab, says more urgent innovation is needed to formulate safe sunscreen. “If you want to make sunscreen safe, then you need an active ingredient that can be [used] at high doses, doesn’t absorb systemically into the skin and doesn’t cause toxicity,” he says. “Some of the mineral sunscreens, if they’re made correctly, could meet that demand.”

Others emphasize the use of “green chemistry” principles to ensure ingredients don’t persist or cause harm. New formulations, some using natural ingredients, hold promise.

But in Downs’ view, real change won’t happen without prompting from governments and regulatory bodies. “If you were to say in four years or five years, we’re going to ban petrochemical sunscreen chemicals, like they’ve done in Palau [a Western Pacific island nation], you would get a serious investment and activity in true green chemistry innovation to find a hopefully toxicologically safer ingredient and one that doesn’t persistent in the environment.”

An industry move is currently underway to add sun protection factor (SPF) boosters to products to reduce the volume of UV filters used. While this would cut the UV filter pollution load, shifting from one chemical to another without testing for impacts is potentially problematic. “We don’t really know the full extent that some of these compounds can also have on the marine environment,” Hodge says.

“We really need more evidence and more research to fully know exactly what we need to be switching to,” she says. “And we need to find that healthy balance between providing sufficient sun protection whilst also ensuring that our sunscreen ingredients are environmentally conscious.”

Banner image: Scientist Anneliese Hodge collecting seaweed. Research suggests that sunscreen UV filters can impact photosynthesis, growth, chlorophyll and other physiological processes within seaweeds, says Hodge, a Ph.D. student at Plymouth Marine Laboratory in the U.K. Such concerns led experts to call for an urgent investigation of sunscreen chemicals’ environmental impacts. Image courtesy of Plymouth Marine Laboratory.

Citations:

Hodge, A. A., Hopkins, F. E., Saha, M., & Jha, A. N. (2025). Ecotoxicological effects of sunscreen derived organic and inorganic UV filters on marine organisms: A critical review. Marine Pollution Bulletin, 213, 117627. doi:10.1016/j.marpolbul.2025.117627

O’Malley, E., O’Brien, J. W., Verhagen, R., & Mueller, J. F. (2020). Annual release of selected UV filters via effluent from wastewater treatment plants in Australia. Chemosphere, 247, 125887. doi:10.1016/j.chemosphere.2020.125887

Scheele, A., Sutter, K., Karatum, O., Danley-Thomson, A. A., & Redfern, L. K. (2023). Environmental impacts of the ultraviolet filter oxybenzone. Science of The Total Environment, 863, 160966. doi:10.1016/j.scitotenv.2022.160966

Cadena-Aizaga, M. I., Montesdeoca-Esponda, S., Sosa-Ferrera, Z., & Santana-Rodríguez, J. J. (2022). Occurrence and environmental hazard of organic UV filters in seawater and wastewater from Gran Canaria Island (Canary Islands, Spain). Environmental Pollution, 300, 118843. doi:10.1016/j.envpol.2022.118843

Balakrishna, K., Praveenkumarreddy, Y., Nishitha, D., Gopal, C. M., Shenoy, J. K., Bhat, K., … Kumar, M. (2023). Occurrences of UV filters, endocrine disruptive chemicals, alkyl phenolic compounds, fragrances, and hormones in the wastewater and coastal waters of the Antarctica. Environmental Research, 222, 115327. doi:10.1016/j.envres.2023.115327

Vilaplana, M. I., Egea, L. G., Bautista-Chamizo, E., Rodríguez-Romero, A., Tollardo, R., Brun, F. G., … Jiménez-Ramos, R. (2025). The temperate seagrass species Cymodocea nodosa and the associated bacteria co-response to sunscreen pollution. Marine Environmental Research, 208, 107115. doi:10.1016/j.marenvres.2025.107115

Cahova, J., Blahova, J., Marsalek, P., Doubkova, V., Franc, A., Garajová, M., … Svobodova, Z. (2021). The biological activity of the organic UV filter ethylhexyl methoxycinnamate in rainbow trout (Oncorhynchus mykiss). Science of The Total Environment, 774, 145570. doi:10.1016/j.scitotenv.2021.145570

Cocci, P., Mosconi, G., & Palermo, F. A. (2022). Organic UV filters induce toll-like-receptors and related signaling pathways in peripheral blood mononuclear cells of juvenile loggerhead sea turtles (Caretta caretta). Animals, 12(5), 594. doi:10.3390/ani12050594

Gago-Ferrero, P., Alonso, M. B., Bertozzi, C. P., Marigo, J., Barbosa, L., Cremer, M., … Barceló, D. (2013). First determination of UV filters in marine mammals. Octocrylene levels in Franciscana dolphins. Environmental Science & Technology, 47(11), 5619-5625. doi:10.1021/es400675y

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Lee, C. E., Messer, L. F., Wattiez, R., & Matallana-Surget, S. (2025). The invisible threats of sunscreen as a plastic co-pollutant: Impact of a common organic UV filter on biofilm formation and metabolic function in the nascent marine plastisphere. Journal of Hazardous Materials, 495, 139103. doi:10.1016/j.jhazmat.2025.139103

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Mohammed, Y. H., Holmes, A., Haridass, I. N., Sanchez, W. Y., Studier, H., Grice, J. E., … Roberts, M. S. (2019). Support for the safe use of zinc oxide nanoparticle sunscreens: Lack of skin penetration or cellular toxicity after repeated application in volunteers. Journal of Investigative Dermatology, 139(2), 308-315. doi:10.1016/j.jid.2018.08.024

Saweres-Argüelles, C., Ramírez-Novillo, I., Vergara-Barberán, M., Carrasco-Correa, E. J., Lerma-García, M. J., & Simó-Alfonso, E. F. (2023). Skin absorption of inorganic nanoparticles and their toxicity: A review. European Journal of Pharmaceutics and Biopharmaceutics, 182, 128-140. doi:10.1016/j.ejpb.2022.12.010

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Not to burst your bubble, but your gum might be packed with plastic.

A new study found that chewing a single piece releases hundreds — if not thousands — of microplastics into your saliva, which you’re most likely swallowing.

That’s a real blow, especially since a growing body of research suggests these tiny particles may pose a threat to our health, potentially even raising the risk of three chronic, harmful diseases.

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5 New research suggests a larger piece of gum could release up to 3,000 plastic particles. OlegDoroshin – stock.adobe.com

Microplastics — tiny fragments of plastic ranging from 1 nanometer to 5 millimeters in size — are released as larger pieces of plastic break down over time.

Research has shown that humans ingest a stunning amount of plastic every week through the water we drink, the food we eat and the air we breathe.

These dangerous specks have been detected throughout the body, including in the lungs, liver, kidneys, heart, blood, testicles and breast milk. One study even found that the average brain contains an entire spoonful of microplastics.

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Something to chew on

The new study, led by University of California, Los Angeles researchers, aimed to uncover yet another way these harmful particles make their way into our bodies: through chewing gum.

Gum is made from three main ingredients: a rubbery base, sweeteners and flavorings. Natural gums use plant-based materials like chicle or tree sap for the base, while synthetic gums rely on petroleum-based rubber.

“Our initial hypothesis was that the synthetic gums would have a lot more microplastics because the base is a type of plastic,” said Lisa Lowe, a Ph.D. student at UCLA.

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5 Microplastics are tiny fragments smaller than 5 millimeters. Microgen – stock.adobe.com

To find out, Lowe chewed seven pieces each of five brands of synthetic gum and five brands of natural gum. Researchers then measured the number of microplastics in each sample of her saliva.

The results were striking: An average of 100 microplastics were released per gram of gum, with some individual pieces shedding as many as 600.

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Given that a typical piece of gum weighs between 2 and 6 grams, researchers said a larger piece could release up to 3,000 plastic particles.

“Surprisingly, both synthetic and natural gums had similar amounts of microplastics released when we chewed them,” said Lowe.

The research team estimated that if the average person chews between 160 and 180 small sticks of gum per year, they could ingest around 30,000 microplastics annually.

“Our goal is not to alarm anybody,” said Sanjay Mohanty, the project’s principal investigator and an engineering professor at UCLA. “Scientists don’t know if microplastics are unsafe to us or not.”

An invisible threat

Though no human trials have nailed it down, animal studies and research with human cells suggest that microplastics could be harmful to our bodies, potentially damaging cells, triggering inflammation, disrupting organ function and altering immune responses.

New research also points to a troubling connection: Higher exposure to microplastics is associated with a greater prevalence of hypertension, diabetes and stroke.

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5 Higher exposure to microplastics was linked to a greater prevalence of high blood pressure. Pixel-Shot – stock.adobe.com

A study due to be presented next week examined the potential connection between microplastic levels in water and health issues in US coastal and lakeshore communities between 2015 and 2019.

“When we included 154 different socioeconomic and environmental features in our analysis, we didn’t expect microplastics to rank in the top 10 for predicting chronic noncommunicable disease prevalence,” said Sai Rahul Ponnana, a research data scientist at Case Western Reserve University School of Medicine in Ohio and the study’s lead author.

Notably, cancer wasn’t consistently linked to microplastic pollution, a surprising twist that contradicts earlier studies suggesting exposure could be tied to cancers of the lung, liver, breast and prostate.

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5 Studies suggest that microplastics can potentially lead to insulin resistance. Dorde – stock.adobe.com

The researchers stressed that while there’s an association between microplastics and high blood pressure, diabetes and stroke, it doesn’t prove causation.

They said more research is needed to figure out whether microplastics are directly causing these health issues or if they’re just occurring alongside other environmental or lifestyle factors that contribute to disease.

How to protect yourself

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In UCLA’s gum study, most of the microplastics were released within the first two minutes of chewing. So if you want to reduce your potential exposure to microplastics from gum, Lowe suggested chewing one piece for a longer time instead of popping a new one.

Mohanty also urged people to “be mindful” when they’re done chewing.

5 The average American chews about 1.8 pounds of gum annually, which translates to roughly 300 sticks. Seventyfour – stock.adobe.com

“The plastic released into saliva is a small fraction of the plastic that’s in the gum,” he explained, adding that improperly discarded gum creates another layer of pollution.

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Ponnana echoed these sentiments.

“The environment plays a very important role in our health,” he said. “As a result, taking care of our environment means taking care of ourselves.”

Though completely avoiding microplastics may be nearly impossible, experts said there are other steps you can take to limit your exposure.

Start by ditching your plastic water bottle, boiling and filtering tap water, avoiding plastic cutting boards and never microwaving plastic food containers. If you’re a tea drinker, experts recommend opting for tea in paper bags or as loose leaves rather than in plastic bags.