New research suggests that the microplastic-polluted water along America's coasts may be linked to higher rates of certain chronic health conditions among those who live there, including type 2 diabetes, stroke, and coronary artery disease.
The study adds to a growing body of evidence connecting microplastics — tiny particles smaller than 5 millimeters (mm) that develop from the breakdown of plastic waste — to a variety of health risks.
What the Study Found
Using measurements from the National Centers for Environmental Information between 2015 and 2020, researchers analyzed microplastic water pollution within 200 nautical miles of 152 coastal counties along the Atlantic Ocean, Pacific Ocean, and the Gulf of Mexico. Each area’s microplastic pollution levels were categorized as low, medium, high, or very high.
The researchers then compared those measurements to the county-level disease rates, as determined by 2022 population data from the Centers for Disease Control and Prevention (CDC).
Compared with those living near areas with “low” levels of coastal microplastic pollution, those who were close to areas with “very high” levels had:
A 7 percent higher risk of coronary artery disease
“Even after adjusting for demographic and social-environmental vulnerabilities, counties exposed to very high levels of microplastics in nearby ocean waters had significantly higher disease burdens. This suggests that microplastics may represent a novel environmental cardiometabolic risk factor — a critical addition to the broader public health conversation,” says the senior study author Sarju Ganatra, MD, the medical director of sustainability and the vice chair of research in the department of medicine at Lahey Hospital & Medical Center in Burlington, Massachusetts, and president of Sustain Health Solutions.
How Do Microplastics Travel From the Water Into Your Body?
Microplastic debris from plastic waste can be found virtually everywhere, including in bodies of water.
They enter the human body when you swallow them, touch them, or breathe them in.
The researchers involved in the new study theorize that people in coastal communities are apt to inhale microplastic particles from ocean water aerosolization, in which microscopic particles become suspended in the air.
“Studies have shown that microplastics can become airborne through mechanisms like sea spray, wind, or even urban dust, making inhalation a real concern — particularly near the coast where environmental concentrations are higher,” says Dr. Ganatra.
“Additionally, coastal residents may face greater exposure due to contaminated groundwater from seawater intrusion, higher seafood consumption, and proximity to recreational areas with high plastic debris,” he says.
While data suggests that living along the coast equates to higher marine microplastic exposure, Philip Kuriakose, MD, a hematologist who has studied microplastics in human blood, notes that the potential risks aren’t limited to specific geographic areas.
“[People] inhabiting inland areas have their own exposure risk to other non-marine sources of microplastics,” says Dr. Kuriakose, who is also a medical oncologist at the Henry Ford Cancer Institute in Detroit.
Future Microplastic Research Recommendations
Although the study adds to the available evidence linking microplastics to a variety of health issues, the results don’t add up to proving direct harm.
For example, Ganatra notes that the study didn’t measure specific microplastic exposure routes (for example by analyzing blood samples from coastal residents), which may limit how the findings translate to concrete health risks.
According to the microplastics researcher Sai Rahul Ponnana, a research data analyst at the Case Western Reserve University School of Medicine Cardiovascular Research Institute in Cleveland, the study used county-level data rather than a large-scale health record database, so the results may not offer a full picture of how microplastics impact health on an individual level.
Ganatra also says more research is required to better understand how microplastic exposure fits in — and adds up — with exposure to other environmental pollutants and traditional health risk factors.
What Can You Do to Lower Microplastics Exposure?
While you may not be able to completely avoid microplastics, especially if you live in a coastal area, there are some ways you may be able to limit your overall exposure — such as by reducing how often you purchase and use plastic items.
Kuriakose suggests taking microplastics as a potential risk factor for chronic disease seriously.
“For those living in coastal areas, it can only help to be aware of this risk and to be proactive — both in minimizing your own contribution to plastic waste and in remaining unflinching advocates for the population as a whole by choosing healthy lifestyle habits that decrease adding to the present problem,” he says.
EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
Makwana B et al. Marine Microplastic Levels and the Prevalence of Cardiometabolic Diseases in US Coastline Counties. Journal of the American Heart Association. June 2025.
Emily Kay Votruba has copyedited and fact-checked for national magazines, websites, and books since 1997, including Self, GQ, Gourmet, Golf Magazine,Outside, Cornell University Press, Penguin Random House, and Harper's Magazine. Her projects have included cookbooks (Padma Lakshmi's Tangy Tart Hot & Sweet), self-help and advice titles (Mika Brzezinski's Know Your Value: Women, Money, and Getting What You're Worth), memoirs (Larry King's My Remarkable Journey), and science (Now You See It: How the Brain Science of Attention Will Transform How We Live, Work, and Learn, by Cathy Davidson). She started freelancing for Everyday Health in 2016.
Cristina Mutchler is an award-winning journalist with more than a decade of experience covering health and wellness content for national outlets. She previous worked at CNN, Newsy, and the American Academy of Dermatology. A multilingual Latina and published bilingual author, Cristina has a master's degree in Journalism from the E.W. Scripps School of Journalism at Ohio University.
