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As global plastic production grows, so does the concentration of microplastics in our brains

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As global plastic production grows, so does the concentration of microplastics in our brains

Finding microplastics in human body parts is not new: Scientists have uncovered the minuscule waste products in human blood, lungs, brains, hearts and testicles.

But a new study, published Monday in the journal Nature Medicine, shows a lockstep relationship between the amount of plastic found in tissues harvested from human cadavers and the amount being produced by the plastic industry.

As global plastic production has ramped up in the last 20 years, so too has the concentration of these shredded, fossil fuel-derived polymers in human tissue samples.

The findings are “pretty striking,” said Phil Landrigan, director of the Program for Global Public Health and the Common Good at Boston College, who was not affiliated with the research.

The study also showed a concerning correlation between patients who had received a dementia diagnosis before they died and the amount of plastic particles found in their brains — adding to a growing body of research indicating that the presence of these particles in the human body can potentially cause harm.

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The study was published by a team of researchers at the University of New Mexico, Oklahoma State University, Duke University and Universidad del Valle, in Colombia.

The team acquired brain, liver and kidney tissue samples from patients who had undergone autopsies between 2016 and 2024 at the University of New Mexico.

To determine both the concentration and kinds of plastic in the samples, the team visually inspected the samples and applied pyrolysis-gas chromatography–mass spectrometry — a technique that allowed them to analyze the tissue’s chemical composition.

They found that the concentrations of particles in kidney and liver samples were comparable, with an average of 433 micrograms of microplastic per gram of tissue in the liver samples and 404 micrograms per gram of the kidney samples.

But the levels seen in the brain samples — all taken from the frontal lobe — dwarfed those numbers, and showed a jump over time. In the samples they harvested from people who died in 2016, they found average concentrations of 3,345 micrograms/gram. In the 2024 cohort, the average was 4,917.

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“I never would have imagined it was this high,” said Matthew Campen, professor of pharmaceutical sciences at the University of New Mexico. “I certainly don’t feel comfortable with this much plastic in my brain, and I don’t need to wait around 30 more years to find out what happens if the concentrations quadruple.”

The concentrations of microplastics the researchers found were independent of the biological age of the deceased person — it didn’t matter if the person was young or old when they died. What mattered was the year they died — the more recent the death, the more accumulated plastic in the body.

Intrigued by this increase in plastic concentration over time, the researchers obtained more brain tissue samples. This time, they examined brains from people who died between 1997 and 2013. They made sure the cadavers were similarly aged to the ones they had already examined — but could not control for geography. The second cohort all came from people who had died on the East Coast.

Again, the researchers found “significantly increasing trends for total plastics” over time in this second group of samples.

Polyethylene — a plastic polymer used to make things such as plastic bags, milk jugs, shampoo bottles, etc. — was the most common microplastic found in the brain. It comprised 75% of the plastic shards observed in the brain tissue samples. But the researchers also detected polypropylene (the plastic used to make yogurt cups and rigid takeout food containers), polyvinylchloride (which is used in most water pipes), and styrene-butadiene rubber (found in some pneumatic tires, shoe soles, brake pads and electrical insulation).

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The concentration of all of these plastics increased from 2016 to 2024, irrespective of the biological age of the cadaver.

They also noted that brain tissue harvested from patients who’d been diagnosed with dementia had higher concentrations of microplastics than those who hadn’t. Although it was a concerning observation, they noted that their sample size was small, and that hallmarks of dementia include brain tissue atrophy, impaired blood-brain barrier integrity, and poor brain clearance mechanisms — which could themselves lead to microplastic buildup.

Therefore, they could make no claims to causation — just correlation.

Landrigan said the work reinforces our knowledge “that we’re all exposed, that these things actually get into our bodies, into people of all ages” and that it “appears to be getting worse with time.”

He said it adds to the urgency of a Global Plastics Treaty — to cap plastic production — and which reached an impasse at the last round of negotiations in South Korea, in 2024. He said negotiators plan to reconvene later this year.

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According to Landrigan, it’s unclear how the United States, under President Trump, would approach the treaty. If Trump follows the advice of the fossil fuel proponents in his administration, it’s likely the U.S. will vote the deal down — or not even show up.

But if the Robert F. Kennedy Jr. element gets a seat at the table, the U.S. is a wild card, Landrigan said. Kennedy was openly critical of the Biden administration for not doing enough to stanch the flow of microplastics into the environment, and he penned a detailed plan that would ban most hazardous chemicals, reform the recycling infrastructure and curtail the production of plastics.

Landrigan said he has known Kennedy for decades, and would happily sit down with him to present this research and the growing number of studies showing the harms these particles — and the chemicals they carry — cause in the human body.

“I’m a pediatrician with the American Academy of Pediatrics, and we’ve always taken the position that the academy will do what it has to do to protect children’s health. We will always stand up for children. So, if there’s an opening there for conversation with Bobby, why not?” he said.

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Video: NASA Announces Artemis III Crew

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Video: NASA Announces Artemis III Crew

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NASA Announces Artemis III Crew

NASA announced the crew of Artemis III mission, which will fly to low-Earth orbit to test rendezvous and docking maneuvers with one or two lunar landers.

“I am excited to welcome you as the next crew in the Artemis journey to successfully return to the moon — this time to stay.” “I’m honored by the role that I’ve been given. I’m also very humbled by the task in front of us. But first and foremost, I’m grateful.” “So with that, the Artemis II crew, comrade, hands you the baton. You got the controls.” “As you know, we had a significant anomaly at our Launch Complex 36A on May 28. We’ve redoubled our efforts and are moving forward.”

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NASA announced the crew of Artemis III mission, which will fly to low-Earth orbit to test rendezvous and docking maneuvers with one or two lunar landers.

By Alisa Shodiyev Kaff

June 9, 2026

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Santa Monica Mountains’ last steelhead trout survived the Palisades fire — and even had babies

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Santa Monica Mountains’ last steelhead trout survived the Palisades fire — and even had babies

Scientists feared the Santa Monica Mountains’ last remaining steelhead trout were dead, smothered by debris flows unleashed by the Palisades fire.

But the endangered fish surprised them: A team of biologists recently spotted 30 of the rare trout — and 21 babies — in Topanga Creek.

“There was a lot of happy dancing in the creek,” said Rosi Dagit, principal conservation biologist for the Resource Conservation District of the Santa Monica Mountains, which works with public and private landowners to conserve natural resources.

That’s because the steelhead here are endangered, at both the state and federal levels. Once, they swam in most streams of the Santa Monicas, but their numbers plummeted amid overfishing and coastal development. Increasingly frequent wildfire has further stressed their habitat. Topanga Creek, a biodiversity hot spot, is home to their last known population in the mountains that stretch from the Hollywood Hills to Point Mugu in Ventura County.

The trout that were spotted, including this one, are part of a distinct Southern California population that’s listed as endangered at the state and federal levels.

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(RCDSMM Stream Team)

The California Department of Fish and Wildlife spearheaded a complex mission to rescue trout threatened by the Palisades fire that sparked in January 2025.

Time was of the essence. The fire hadn’t yet been fully contained. But rain was on the way, which would sweep massive amounts of sediment from the denuded hillsides into the water. Fish are often killed this way.

Crews stunned the fish with electricity, scooped them up in buckets, trucked them to a hatchery and ultimately moved them to Arroyo Hondo Creek in Santa Barbara County.

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Within days, Topanga Creek was choked with mud. Some assumed the fish left behind were goners.

But in March, the conservation district’s team found four. The following month, when water conditions were clearer, they saw more.

“These fish continue to amaze me,” said Kyle Evans, environmental program manager for the state Department of Fish and Wildlife, who had seen the damage to the creek. “I had seen populations get wiped out in similar situations. So when I heard, I was thrilled.”

Evans surmises the fish that survived were in an area of the creek where less charred material and sediment were swept in.

“These fish likely hunkered down, were hiding under some rocks or places to try to get away from the main concentration of flow,” he said. “And luckily they weren’t buried.”

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The ones that were spotted were fairly small, around 6 to 14 inches. Rainbow trout and steelhead trout are the same species, but with different lifestyles. If the fish remain in freshwater, they’ll be considered rainbows. However, they can migrate to the ocean and become steelhead, where they typically grow larger before returning to their natal waters to spawn.

Topanga Creek hasn’t fully recovered from the damage it sustained, but scientists say it’s looking better. Surveys last year were “so depressing,” Dagit said, with very few animals, and stretches that were essentially transformed into flat roads from all the sediment buildup. Some of the riparian canopy burned right down to the creek.

Then came 32 inches of rain over the last nine months, scouring out and moving sediment, creating deeper pools. Dagit said they recently found newt egg masses for the first time in years, as well as a few adult newts and many frogs. Plants that provide cover are starting to recover.

She provided photos comparing certain pools last year and this year, some dramatically transformed. In September 2025, the Shrine Pool could have been an overgrown hiking trail. This April, it was filled with shallow water.

Shrine Pool, Sept. 2025, left, and the same location, April 2026, right.

The Shrine Pool in September 2025, left, and the same location in April 2026, right, with RCDSMM’s Isaac Yelchin donning a wetsuit.

(RCDSMM Stream Team)

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Topanga Creek is home to another endangered fish, the small but hardy northern tidewater goby, often described as cute. Not long before the trout operation, Dagit led a rescue of hundreds of these fish too. Many were repatriated to the lagoon at the mouth of the creek in a moving ceremony last June.

There’s still the matter of what to do with the trout that were moved to Santa Barbara County last year. Evans would like to bring them home to the Santa Monicas at some point, but isn’t sure if it will happen. On one hand, they could bolster the small, genetically isolated surviving population. On the other, they might inadvertently bring in a disease or bacteria. There is some time to decide. Evans estimates the creek still needs to recover for two to three more years.

For now, the fish are functioning fine in their adopted creek. Experts worried the trauma wrought by the move would disrupt their spawning process, but they had babies that spring. This year, they spawned again.

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Pacifica pier cracks, another coastal casualty as seas continue to rise

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Pacifica pier cracks, another coastal casualty as seas continue to rise

The Pacifica Municipal Pier was shut down and taped off Thursday after city workers noticed cracks running through the landmark structure and concrete chunks falling into the ocean.

It’s just one of many coastal California structures that have recently crumbled under pressure from a rising and relentless ocean.

Officials from the small, beach city south of San Francisco said the pier was closed due to “cracking, separation, and displacement of the concrete walkway and structural elements.”

It will stay closed while structural engineers asses its safety.

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Photos taken by city employees show a wide crack that runs from top to bottom and across the structure as well. Other photos show a large horizontal crack under the foundation of a small restaurant on the pier, the Chit Chat Cafe.

The cafe was also shut down.

This is not the first time the 53-year-old pier has shown signs of stress. In 2021, part of it was shut down after handrails along the edge collapsed. And in 2023, after a series of storms pummeled the Central California coast, damaging parts of the pier, the structure was partially closed for more than year.

Those same storms caused extensive damage in Aptos and Capitola, 70 miles south, where piers and waterfront infrastructure were swept away or damaged.

In 2024, a 150- to 180- foot section of the Santa Cruz wharf was ripped off by powerful waves.

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At least 10 of the state’s dozens of coastal public piers were closed for part or all of 2024 due to structural damage sustained in winter storms since 2022. At least five others have longer-term upgrades planned to address structural issues.

“These things are costly to maintain,” said Zach Plopper, senior environmental director at Surfrider. “They are a part of our California coastal culture in many ways, but we’re going to need to reckon with, one, the state that they’re in, and two, the continuous and worsening threats they’re going to experience,”

He said most of the piers were constructed in the early 1900s, and they weren’t built to withstand decades of rough seas, storms and rising sea level.

“With this incoming El Niño, which is forecasted to be significant, and this marine heat wave we’re in the midst of, we’re kind of in uncharted waters as far as what this winter could bring in terms of storms and swells to the California coast, and we’re likely going to see a lot more damage,” he said. “Not just piers, but roads and other coastal infrastructure up and down the state.”

There was no storm in Pacifica earlier this week, so no single event could be blamed for the destruction.

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However, a 2025 report from an outside engineering firm, GHD, found that several sections of the pier were in “poor” or “serious” condition, and they recommended closure before anticipated storms or events that could “subject the piles to high winds, swells and large waves.”

The firm found several areas of the pier where concrete was missing and rebar was exposed and corroding.

“The pier has continued to experience high winds and large waves in a harsh marine environment,” the engineers wrote in the report, noting that continuous exposure to seawater or marine spray was “detrimental” to the structure.

A 2023 city report estimated it would cost $19 million to repair.

That same year, a state law was enacted to require local governments along the California coast to plan for sea level rise in the coming decades.

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Sea level has risen some 8 inches, on average, along the coast in the past 150 years, Plopper said, and researchers anticipate another foot in the next 25 years.

“We’re going to see profound shifts on our coastline, none that we have ever experienced before, and building static structures on the coast just doesn’t work all that well,” he said. “We’re going to have to make some really hard decisions.”

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