top of page
Writer's pictureFederico Cárdenas

Microplastics are everywhere, from water to food. What you need to know about the health impacts of microplastics.


How can you stay safe from microplastics? Are they causing cancer in young people? Should you ditch your plastic water bottle? What about eating seafood? Everything you need to know to stay safe from microplastics.

 

 July 22, 2024

Microplastics are tiny particles of plastic, smaller than 5 millimeters. They come from larger objects that break down and degrade over time, such water bottles and food packaging. Photo: Getty Images.

Microplastics are everywhere. From an infant’s first poop to the depths of the Mariana Trench, the tiny particles are impossible to avoid.

How big of a deal is that?

While interest has skyrocketed in recent years, science is still racing to catch up. Some evidence suggests microplastics could be linked to cancer, infertility, heart disease, kidney disease, Alzheimer’s disease and more.

Scientists like Dr. Suzhao Li are working to answer that call.

Li, who has both medical and doctorate degrees, is an associate research professor at the University of Colorado Anschutz Medical Campus. She specializes in infectious disease and inflammation immunology.

When she first heard about microplastics years ago, she didn’t pay much attention. Like most of us, she drank water out of plastic bottles and ate food that came in plastic packaging. She certainly didn’t think microplastics would become an important part of her job.

But as more research was published, microplastics and their potential health impacts became a focus for Li.

When did you start paying attention to microplastics?

“I started hearing about microplastics when my friends, who are chemists, started talking about how we eat a lot of plastic. At first, I didn’t pay much attention,” Li said.

“I started to pay more attention with news coverage of microplastics and the research and reports coming out about them.”

Microplastics are foreign to the human body, she said. When foreign materials enter the body, our immune cells try to figure out what they are and react accordingly.

What are microplastics?

Microplastics are tiny particles of plastic, smaller than 5 millimeters. They come from larger objects that break down and degrade over time, such as plastic bags, water bottles, phone cases, clothes, food packaging, car tires, paint coatings, clothing and more. Some are even intentionally added to products such as abrasive cleaners or cosmetics.

How are we exposed to microplastics?

According to a study published in Environment & Health, humans are exposed to microplastics in three ways:

·       Oral intake

·       Inhalation

·       Skin contact

Oral intake is the most common route, according to the study, driven by things people use and consume on a daily basis such as drinking water, takeout containers, silicone baby bottle teats, bottled water, salt, seafood, sugar, tea bags, milk and more.

Microplastics are thought to enter our food system in two major ways. One way is through the meat we eat. When animals consume microplastics somewhere along the food chain, they accumulate, potentially ending up in the hamburger we just enjoyed.

Another way is through plant matter. Microplastics enter the agriculture system in a variety of ways, some including compost, plastic mulching, or sewage sludge, ending up in the soil. From there, they are thought to work their way through a plant’s water transport system, spreading to the roots, stems, leaves, and fruits of the plant.

We also inhale microplastics. According to the study, one of the largest sources of microplastics in the atmosphere comes from the roads we drive. Another study, published in the Journal of Hazardous Materials in 2021, found microplastic particles in human lung tissue.

We are also exposed to microplastics when we encounter everyday objects such as cell phone cases. Though experts don’t think microplastics pass through the skin barrier, tiny particles may end up on your hands, in your eyes, in your mouth and more.

What do we know about the health impacts of microplastics?

The short answer is not much – yet. But expect that to change.

Most research on microplastics hasn’t directly focused on humans; instead, it has examined effects on things like cells, artificially grown cells that resemble organs, and animals.

“More evidence is showing microplastics can be accumulated in the human body, so I think that will lead to more research,” Li said.

While her research will likely focus on how our immune cells react when they encounter microplastics, a recent study published in the New England Journal of Medicine in March caught Li’s eye.

Researchers followed patients undergoing surgery to remove plaque buildup as treatment for heart disease. Researchers then examined the plaque and found micro and nanoplastics. The study linked those plastic particles to an increased rate of heart problems among patients enrolled in the study.

According to the study, patients with plastic found in their plaques had 4.5 times the risk of complications such as heart attacks, strokes, or death compared to patients without plastic in their plaques.

Researchers found polyethylene and polyvinyl chloride in the plaques. Polyethylene is commonly found in plastic bags and bottles. Polyvinyl chloride is often used in medical devices, pipes and insulation. High resolution images from electron microscopy also showed “visible, jagged-edged foreign particles” in the plaques.

According to research published in Science, studies of human cell cultures and rodents suggest inhaled or ingested microplastics are associated with cellular damage, inflammatory and immune reactions, DNA damage, neurotoxic and metabolic effects. However, the negative effects were seen with concentrations of microplastics we don’t typically encounter in a real-world setting. The existing studies also can’t yet account for whether the microplastic particles were contaminated with other chemicals and what effect that might have had on the results of the study.

Another study found more microplastics in tumorous colon tissue than in non-tumorous and control tissue, suggesting an association between colorectal cancer and exposure to microplastics, but researchers cautioned that further studies were needed before drawing conclusions.

The next best thing (maybe)

While we don’t know much about the health impacts of microplastics yet, we do know about particulate air pollution.

John Adgate, who has a Ph.D. in environmental health and a master’s in environmental sciences and engineering, is a professor at the Colorado School of Public Health Department of Environmental & Occupational Health. In many ways, particulate air pollution is comparable to microplastics, Adgate said.

A hair on your head is about 70 microns in diameter, Adgate said. We can breathe in air particles with a diameter of 10 microns or less, and those air particles can cause health problems. Particles with a diameter of 2.5 microns or less are known as fine particulate matter.

“The small particles less than 2.5 microns can get way down deep in your lungs and pass through some of your lung cells and even into the blood stream,” he said. “Those come from things like diesel, wood smoke, wildfire smoke, things like that. That’s well established.”

Microplastics are very similar in terms of size, Adgate said.

But microplastics don’t break down in the same way air pollution does, he said. Air pollution particles are soluble, meaning they eventually dissolve.

“The real question with microplastics is this – they’re everywhere, we consume a lot of them either by breathing them in or through food, do they build up in the body anywhere? Will that cause problems?”

Where in the body have microplastics been found?

Researchers have found microplastics in the spleen, liver, colon, lung, feces, placenta, breastmilk, human blood and more – with particularly high concentrations found in the colon and liver. Because they have been found in blood, microplastics are thought to circulate through the entire body.

How can I limit my exposure to microplastics?

If microplastics are in food, air, soil, roads and more, it might seem like they are impossible to avoid. And they are. But there are steps you can take to reduce your exposure.

Li recommends microwaving food in ceramic or glass containers – especially frozen food that comes wrapped in plastic.

“Sometimes you’re busy and you need food that is easy to make,” Li said. “I recommend you transfer containers.”

Li also recommends minimizing use of plastic objects like plastic water bottles, but she said if you have to use them, avoid putting that plastic in contact with direct heat and sunlight.

If I want to avoid ingesting microplastics, should I avoid eating seafood?

“We see lots of news reports and images of plastic floating in the ocean and hear about the impact of plastic on sea animals,” Li said. “But seafood is an important food resource for humans with key nutrients and lots of good benefits. I don’t think at this moment we have to worry or eat less seafood. But we could do more to protect our ocean.”

What’s next in biomedical research?

Li said she is learning more about the impact and health effects of microplastics through her research on inflammation, innate immunity and the direct effect on human cells.

“We have some data showing microplastics can affect cell morphology, and that different people have different immune responses to them,” she said.

With more funding and time, Li said she’d like to learn more about the cumulative effect of microplastics on the immune system and better understand the effects of long-term exposure.

What’s next in research related to microplastics?

Scientists are also working to innovate plastic itself.

Wei Zhang is a professor at the University of Colorado in Boulder and has a doctorate in chemistry. Zhang and his team collaborate with Li.

“Plastics are very important, obviously,” Zhang said. “It’s just not practical or feasible to ban everything or stop using them.”

Plastics serve important roles in society, Zhang said. One of the key components that make plastics so useful is their barrier properties.

“During the pandemic for example, medical staff and frontline workers were protected by plastic,” he said. “The gloves, the coats, the face shields – pretty much everything was made from plastic. Without those materials, how can medical workers help patients?”

For now, plastics are irreplaceable in the medical field, he said.

But the technology does exist to make alternatives for other situations, he said.

These alternatives are just expensive.

Zhang and his team are working on developing new materials that have similar functional properties – think lightweight, flexible, protective barriers – but are considered closed loop recyclable materials. This means that there is a true beginning and end of life for the material. As the plastic degrades, it will revert to molecules rather than micro or nanoplastics, he said.

To make better, safer, nicer material, he said, it’s important for chemists and material scientists to work with biomedical scientists like Li.

“We have to do fundamental tests to make sure the material really is better, more benign, more user friendly, and really degrades,” he said.

Zhang said he has noticed an increase in public interest in microplastics in recent years.

He often participates in the CU Wizards program, a free monthly show put on by the university to entertain and inform children about science.

“I was a little bit surprised. One little kid raised his hand and asked about microplastics,” Zhang said. “This generation is already aware of microplastic pollution. The general public has more of an understanding of it, and that’s great. We need more people joining the team.”

 

 

Sincerely,

 

Phil Ruschmeyer

 

President & CEO

RUSCHMEYER CORPORATION

Commercial Real Estate Advisors

Equity/Debt Consultation

 

303-800-9999

 

Dairy Block

1800 Wazee Street

Suite 300

Denver CO 80202

7 views0 comments

コメント


bottom of page