Nanoplastics can bypass the blood-brain barrier and may harm the nervous system

Research shows that microplastics and nanoplastics can accumulate in major arteries, and patients with these deposits are significantly more likely to suffer heart attacks, strokes, or death.

Microplastics are infiltrating the human body with unclear but concerning effects

Scientists have linked microplastics to immune system damage, hormone disruption, inflammatory diseases, and even cancer—yet most of their health impacts remain unknown due to limited research. Studies suggest we ingest about a credit card's worth of plastic weekly.

Research shows that over 1,000 metric tons of microplastics fall on national parks every year—equivalent to 120 million bottles of water.

Microplastics have been identified across human body systems, with research finding they are most commonly ingested through inhalation, drinking water, and diet before crossing barriers into organs.

As of 2025, the FDA states that microplastics have not yet been shown to pose a risk to human health, though it acknowledges that evidence suggests microplastics and nanoplastics have entered the food supply.

In Indonesia, microplastics rain down when trash is burned, and people may ingest the equivalent of 3 credit cards per month—on average.

BPA-free plastics may still pose health risks because they often contain other structurally similar chemicals.

Microplastics 101: What we know about the contaminants invading our bodies

Fifty-one trillion particles of microplastics float in our oceans. Yet there is very little science of how this affects our health. This quick 2-minute video explains the dangers of microplastics.

Microplastics have been found everywhere there is liquid or vapor water, from the oceans and tropical waters to polar ice and the air we breathe, posing growing risks to wildlife and ecosystems.

Mermaid tears are a long-lasting and hazardous form of ocean microplastic pollution, whose chemical composition enables them to contain higher concentrations of certain toxins than the surrounding environment.

Nanotechnology refers to the study of objects measuring 1 to 100 billionths of a meter, which has produced materials with unique properties by manipulating the arrangement of atoms.

Microplastics have been found across all of Earth's depths and altitudes, from plastic debris in the Mariana Trench to fragments found in snow samples near the summit of Mount Everest.

Microplastics are entering human food chains through carrots, wheat, and other foodstuffs grown in farmlands fertilized by sewage sludge.

The prevalence of microplastics came from plastic’s affordability and versatility

Microplastics' durability and overuse have led to massive pollution that overwhelms the planet's ecosystems. Avian, terrestrial, and marine life have been observed to contain microplastics in their bodies, but reverting to paper, cotton, and other materials in manufacturing also brings environmental challenges.

Used since the 1940s, 'forever chemicals' include thousands of different types of substances routinely integrated into industry and consumer products, yet research suggests they can accumulate in the body over time.

Research suggests microplastics disrupt photosynthesis in plants and algae, and this damage in crops may already rival the impact of climate change on food supplies.

Scientists have found that sewage sludge used as fertilizer introduces various microplastics into soil, which persist in farmland for decades.

Most plastics are not biodegradable because breaking their chemical bonds requires temperatures lethal to most microbes, and these organisms have not been exposed to plastic long enough to evolve the necessary enzymes.

Watch 'Last Week Tonight' explore the risks of 'forever chemicals,' a group of human-made chemicals used in everyday products to make them resistant to water, stains, grease, and heat. (Warning: language.)

Airborne microplastics may influence cloud formation and climate

Microplastics are increasingly found in the atmosphere and may affect the climate by reflecting or absorbing sunlight based on their pigmentation. Like mineral dust, they may become cloud seeders and alter regional precipitation patterns as they become more abundant.

View the estimated decomposition times for various everyday plastic products, which often fragment into smaller microplastics as molecular bonds are weakened by sunlight.

How plastic manufacturing could be sustainable again

From polymers to nurdles, learn how plastic is created and what we can do to slow the lasting repercussions this material will have on both our planet and our lives.

Fentanyl is better at crossing the blood-brain barrier than other opioids

Among opioids, fentanyl is uniquely adept at crossing the blood-brain barrier—the brain's security fence against harmful substances. This enables a lightning-fast high. It ends just as quickly, sometimes within minutes (where a heroin high lasts hours), and still results in the same withdrawal symptoms.

What is the blood brain barrier?

Every blood vessel is lined with endothelial cells that act as filters between blood and the rest of the body. In the brain, these cells are tightly packed together to keep a close watch on what substances can access the vital organ. This protective measure poses an obstacle to drugmakers looking to deliver drugs to the well-defended brain for conditions like Alzheimer's. Watch a quick overview here.

Synthetic textiles and tires account for more than 60% of ocean microplastic pollution, which enters the seas via runoff and wastewater discharge.

Neural interfaces offer major medical potential but raise serious ethical concerns

Although brain-computer interfaces can help people recover lost functions and allow direct brain-to-computer communication in the future, surveys have shown little public support for using them to boost abilities like memory or focus in healthy people.

The challenges of trying to study microplastics in microplastic-abundant labs

The presence of microplastics in instruments, surfaces, and air has made accurate measurement of their levels in lab samples difficult, given the high likelihood of contamination. While the use of stainless steel tools in a sealed, clean lab may reduce accidental exposure, existing methods can misidentify biological substances, such as fat, as plastics, further complicating research.

The amount of plastic chemicals in 300 everyday Bay Area foods

Food production is more complicated than it appears, and manufacturing, packaging, and shipping processes can add significant substances to your food. This massive project compiled data on 300 samples of foods delivered to the San Francisco area, testing for the presence of 18 different kind of plastic. Learn how to read the data here with its helpful guides and then explore the table yourself.

Forever chemicals accumulate up the food web, with recent research indicating that apex predators have higher concentrations because they're eating prey that also have accumulated the substances.

Researchers are investigating if nanoparticle treatments could combat allergies

In rodent work, Northwestern University’s Evan Scott (now at the University of Virginia) and his colleagues have been trying to attack allergies with specially designed nanoparticles—miniscule lab-made objects that can penetrate cells. They stud the nanoparticles with a tiny bit of the allergen specific to the allergy (i.e. cashew protein for cashew allergy) and antibodies that shut down allergic response processes.

Chronic drug use can cause neurological changes in the brain

Neuroscientist Judy Grisel breaks down the biology of addiction, examining how drugs hijack the brain’s natural reward system and create lasting neural changes. The physiological and neurological impacts of chronic drug use require a multifaceted treatment approach.

Plastic debris across the ocean aids the spread of invasive species

The durable, long-lasting material can serve as a platform for living organisms to latch onto and ride over vast distances. After the 2011 earthquake and tsunami in Japan, a large dock carrying 100 tons of living organisms native to Japan washed up on Oregon's coastline, confirming the ecological threat.

See this interactive global map that highlights which forever chemicals have been detected in specific wildlife species, providing data on hundreds of species exposed to these hard-to-breakdown substances.

Many plastic products are molded from melted pellets called nurdles, which are made from ethylene and propylene extracted from crude oil.

The risks of bioremediation, from intermediate products to ecological disruption

A step in the series of complex biochemical reactions involved in the implemented bioremediation process may produce dangerous molecules—sometimes more toxic than the initial pollutants—that require ongoing monitoring to ensure optimal conditions for processing these intermediates toward the eventual, safe outputs. Introducing non-native nutrients or species, including GMOs, may alter existing food webs and gene pools.

Forever chemicals are so common that experts concluded in 2022 that it's uncertain whether limiting consumer exposure would truly reduce one's exposure to these substances, and noted it would still take years for the body to clear them.

From soil to beer, microplastic pollution is all around us

Marine plastic pollution has been studied for decades, but the extent and effects of plastic pollution elsewhere is only just beginning to be explored.

25 million pounds of beads are distributed every Mardi Gras, leading to environmental concerns

The necklaces—which are mostly made from cheap, often toxic, plastic—are believed to be harmful to New Orleans and its residents. Dr. Howard Mielke, an environmental scientist at Tulane University, found that the majority of lead in the city's soil can be found along Mardi Gras parade routes.

During wash cycles, synthetic fabrics shed millions of plastic microfibers, making them a significant source of global microfiber pollution.

The global plastic crisis in images

For decades we have relied on plastics to keep us safe, insulate our homes, and make sure our food stays fresh. But when does plastic's life come to an end?

Implanted neurotechnology can leave users vulnerable when manufacturers go under

Despite providing relief from neurological conditions, patients are left stranded when the companies that make these devices shut down. The lack of regulation means patients often face technical failure, insurance battles, or risky surgeries to maintain their quality of life.

Why bacterial bioremediation may help counter the negative effects of past chemical solutions

Molecules such as DDT, a synthetic insecticide, and PFAS—"forever" chemicals used to make products resistant to heat, water, and grease—have historically been used across various industries but are now known to be harmful. Microbes that can convert some of these substances into nontoxic products, such as water and carbon dioxide, have already been identified, with ongoing research to find others.

Most biodegradable plastics don’t break down in everyday conditions

Despite their eco-friendly name, biodegradable plastics often require industrial composting, which most areas lack, to decompose the uncommon compounds found in them. This means they may linger in landfills or contaminate conventional plastics in recycling bins.

The US FDA issued a 2025 warning about BPC-157 and other popular peptides that are marketed for various regenerative properties.

What sleep loss does to the brain

Proteins in the brain perform various critical functions, such as helping neurotransmitters function or enabling electrical activity in the organ. These proteins must fold in specific ways to perform their duties, similar to paper airplanes. Sleep deprivation contributes to the gathering of misfolded proteins that aren't shaped correctly for their roles and so accumulate in undesired spaces, such as in the gaps between neurons.

Despite being derived from crude oil, which itself comes from organic material, synthetic plastic isn't biodegradable because it hasn't existed long enough for microbes to have developed mechanisms to break it down.

Predictive brain implants raise ethical concerns about patient autonomy after surgery

These devices can accurately forecast neurological events like seizures and suggest or even automatically deliver responses. Their constant monitoring and prescriptive functions may blur the line between patient choice and device influence.

The history of natural and synthetic plastics

From cheap toys to woolly jumpers, plastic can be found in more products than many people realize. From a chemist's perspective all these things are made of the same class of materials: Polymers. And the distinction between which ones we happen to call "plastics" and which ones we don't is fairly arbitrary.

Necrosis is the unplanned death of cells and the tissue they comprise

If cells die prematurely due to a lack of blood flow, injury, or disease, they and their organelles can swell, leading to rupture of the surrounding cell membrane. This releases the cell's contents into the surrounding tissue, causing inflammation and damage to neighboring cells.

As of 2023, more than 130 nations have enacted bans or restrictions on plastic items, starting with Bangladesh's ban on plastic bags in 2002.