Lab race to find out what microplastics do to our bodies

At the University of New Mexico's Underground Research Institute, Marcus Garcia ran through bottles full of plastic waste. He chose past bottles, fishing net chunks, toothbrushes, cups with Pokemon characters, and GI Joe.

“Yes!” he cried, lifting up the tip of the abandoned pipette. “i got you.”

Dr. Garcia, a postdoctoral researcher in Pharmaceutical Science, discovered tips for pipettes with a colleague from Remote Hawaii Beach last summer. It was miraculously unharmed, but it probably had degraded to the sun, ozone and the ocean for years. I thought it was so poignant. It was an object used daily by him and thousands of other scientists. And there they were washed down on the beach along with hundreds of other pounds of other plastic waste they are now cleaning and collecting for research.

Dr. Garcia is part of a major lab run by toxicologist Matthew Campen, studying how small particles, known as microplastics, accumulate in our bodies. Researcher Latest papersIt was published in Natural Medicine in February and generated a series of incredible headlines and buzz in the scientific community. They found that 2024 human brain samples had nearly 50% microplastics than 2016 brain samples.

“Things like this are increasing exponentially in our world,” Dr. Kampen said. It's stacked up in our environment, so it's stacked up within us too.

Some of the researchers' other findings also encourage broader concerns. In this study, the brains of people with dementia had far more microplastics than the brains of people without it. In a paper last year, researchers showed that microplastics exist in humans Testis and placenta. Other scientists also include blood, semen, breast milk, and even Baby's first stool.

In February, Dr. Kampen's lab was released along with colleagues from Baylor College of Medicine and Texas Children's Hospital. Preliminary investigation This shows that preterm babies' placentas contained more microplastics than those babies' placentas that gave birth at a term, despite their less time to accumulate.

However, researchers still didn't understand where they found microplastics and all concerns about health risks. The first thing a toxicologist learns is that “dose creates poison.” Any substance, even water, can become toxic in sufficient quantities. However, Dr. Campen and Garcia didn't know how much microplastic it took to cause health problems. And with so many plastics in our world, was it our food, clothing, air, or other sources that pose the biggest threat?

To begin answering these questions, they turned to the corpses.

I'm looking for plastic

Down the hall from Dr. Garcia's search, the team's main lab cabinet held samples from the brain, liver, kidneys, arteries and genitals.

Dr. Garcia opened a bottle labeled “DB” for “Dementia Brain.” It emitted a familiar smell to those who spent time in formaldehyde, an anatomy lab. Using tweezers, he picked a portion of the brain tissue and placed it on a glass Petri dish. It resembles tofu, with thick gray matter surrounding a narrow white band.

In their paper, the researchers reported that the median concentration of microplastics in the 24 human brains in 2024 was close to 5,000 micrograms per gram, but there is considerable uncertainty in its estimates due to the method used in the calculations. It's about 7 grams of plastic per brain. As much as it would make up a disposable spoon, Dr. Kampen said. Although people with dementia had more brains, researchers noted that these brains have a more porous blood-brain barrier and are unable to remove toxins.

It is not yet clear how this amount of plastic will affect human health, but it is sufficient to cause an alarm. “I don't think I've spoken to one person who said, 'Great! I want to know that there's all the plastic in my brain,” Dr. Kampen said.

His group is currently studying tissues from a single brain section to see if a particular area has a higher microplastic concentration and whether it can be linked to issues such as Parkinson's disease and memory loss. Ideally, for comparison, he wants to study the brain from the 1970s or 1960s, when plastic became ubiquitous. “You can imagine a classic old museum of brains floating in bottles,” he said. “I really need one of them.”

Experiments are expensive and time consuming. Brain samples are not easy to get. A plastic analyzing machine costs around $150,000 per pop. (Next to the oldest one, my research assistant placed a candle with a photo of Jesus and the words “I trust you.”

However, these studies have enabled Dr. Kampen to draw certain conclusions that no one else has. They made us believe that our bodies microplastics are much smaller than what other scientists have described. He used a high-resolution microscope to confirm his suspicions. It showed shard-like fragments less than 200 nanometers in length. 400 times less than the width of your hair – And they were very thin and translucent. Previous studies used microscopes that can only be seen up to 25 times their size.

For Dr. Kampen, documenting very small particles has allowed us to gain a better understanding of the amount of plastic we have inside us, how it will reach, where it will go, and what damage it will do.

Going back decades ago

Researchers can't say for certain how these plastics come in our bodies, or where they came from, but there are a few clues. They know that plastic waste ends in our soil, water, air and even rain, said Christy Tyler, a professor of environmental science at Rochester Institute of Technology, who studies microplastics in aquatic ecosystems. It may be integrated into the plant and concentrate as it moves the food chain. Plastic can be found in clothing, rugs, sofas and food storage containers. “It's really everywhere,” Dr. Tyler said.

The characteristics of the plastics discovered by Dr. Kampen's team in human tissue suggest that they came mainly from waste produced many years ago and weathered over time. Researchers discovered a significant amount of polyethylene, for example, a major type of plastic produced in the 1960s, but in the 1990s, fewer plastics were used in water bottles.

Plastic production doubles every 10-15 years, so even if we stop working today, we still have a lot of plastic waste already in use, and, potentially, more and more plastic waste is building up in our bodies over the next few decades, in the environment and potentially.

Dr. Kampen suspects that the main way these plastics get inside our bodies is when we take them after they've been thrown away and start to break down. He isn't too worried about what is called fresh plastic. This is like the ones that we use, strip off cutting boards and water bottles, and those particles are much bigger and newer than what he measured. And research suggests the body Clear some larger microplastics.

Dr. Kampen admits that his view on fresh plastic is “unconventional” and says other scientists are worth taking steps to reduce your exposure. It is clear that microplastics can leach from water bottles, microwave food containers and synthetic clothing. Animal studies suggest that these particles may be harmful.

“Maybe it's coming from this degraded microplastic, but that doesn't mean you're not exposed from these other fresh microplastics,” Dr. Woodruff said. Dr. Kampen said larger particles could still affect the intestines, which could affect the rest of the body.

Additionally, scientists believe certain chemicals, such as phthalates, bisphenol A and flame retardants, can damage human health. “There's been years of research into these plastics,” Dr. Woodruff said. “But we still have a lot of science like, 'Wow, I know I don't want to be exposed to plastic any more.” ”

Dr. Tyler said the University of New Mexico Labs did the best possible job in such an early field. “Matt's group is very cutting edge,” she said.

But like any science, there is a warning. One is that these small particles are very difficult to measure. And no one has yet to repeat the research to see if the results will continue. The big question is whether everything they measure is actually plastic, or whether some of it is lipids. This is chemically similar, but can occur naturally in the body.

“We estimate that your brain costs are high,” Dr. Woodruff said. But even if they were, she said, “it wouldn't deny the discovery that they're seeing more plastic over time, and that's actually very consistent with what we know about the production of plastic.”

Addressing health risks

There is one question that Dr. Kampen and Garcia feel they have begun to answer with confidence. That's what they started: how much plastic does our bodies have?

Now they are ready to explore possible links between specific doses and human health outcomes such as heart disease, fertility issues, and multiple sclerosis.

And they've begun experimenting with animals and understand what the dosage can be harmful.

Teya Garland, a pharmacy student, had begun the process in her lab. Wearing a mask to avoid inhalation of particles, she inserted a bit of what looked like a coloured chalk into a machine that creepyly howled it as it froze and crushed the plastic. Finally, researchers will supply them to mice and study how different levels and types affect the brain and behavior.

The work came from a beach in Hawaii. In Hawaii, Dr. Garcia and others collected 1,800 pounds of plastic debris and a 500 pound net. Volunteers there will be clarification about the amount every few weeks.

“Looking at the photos is one thing,” Dr. Garcia said after seeing the video he had taken over the phone. “It just opens your eyes to see it when we were there,” he added. All the use of plastic, including take-out containers, bleach bottles, cigarettes, plastic bags, and even equipment, seemed to be represented by its beach and the oceans stretching beyond. And every day it was broken and smaller and smaller.

One day, some of it could end up with us.

Manufactured audio Patricia Surbalan.