A new study from Case Western Reserve School of Medicine has found that communities exposed to higher concentrations of microplastic pollution experience significantly higher rates of chronic noncommunicable diseases (NCDs), including hypertension, diabetes, and stroke.
The research, presented at the American College of Cardiology Annual Scientific Session (ACC.25), adds to growing evidence that environmental pollutants may be contributing to the rising burden of cardiovascular disease in the United States.
Study Links Microplastics to Chronic Disease Prevalence
Researchers examined 555 U.S. census tracts located within 200 meters of large bodies of water, where microplastics concentration data are more reliably available. They merged environmental data with disease prevalence statistics from the CDC PLACES database and analyzed 154 additional socioeconomic and environmental factors, including income, employment, social vulnerability, and air pollution.
The analysis revealed strong associations between microplastic pollution and NCDs across U.S. coastal regions. Areas with higher microplastic concentrations showed positive correlations with rates of high blood pressure (correlation coefficient r = 0.24), diabetes (r = 0.3), and stroke (r = 0.26). Interestingly, cancer rates initially showed a negative correlation (r = -0.16), though subsequent analysis of variance indicated an association between microplastic concentration and cancer risk.
"This study provides initial evidence that microplastics exposure has an impact on cardiovascular health, especially chronic, noncommunicable conditions like high blood pressure, diabetes, and stroke," said Sai Rahul Ponnana, MA, research data scientist at Case Western Reserve School of Medicine and lead author of the study. "When we included 154 different socioeconomic and environmental features in our analysis, we didn't expect microplastics to rank in the top 10 for predicting chronic noncommunicable disease prevalence."
Advanced Analysis Confirms Significance
The research team employed a machine learning model called XGBoost to predict disease prevalence and assess the relative importance of each variable. Microplastic concentration emerged as a top contributor, particularly in predicting stroke prevalence.
These findings held up under additional analysis of variance, which showed statistically significant differences in NCD prevalence based on levels of microplastic exposure.
Understanding Microplastics Exposure
Microplastics are plastic fragments measuring between 1 nanometer and 5 millimeters that are released when larger plastics degrade. For comparison, a strand of human hair is about 80,000 nanometers wide. These particles have become ubiquitous in our environment, with human exposure occurring through ingestion or inhalation from drinking water, food, and air.
The particles can originate from food and beverage packaging, consumer products, and building materials. Their small size allows them to enter the human body through multiple pathways, potentially affecting various physiological systems.
Broader Context of Environmental Health Risks
This research contributes to a growing body of evidence on environmental pollution and health outcomes. Previous studies have established causal relationships between air pollutants and increased cardiovascular disease risk. Other research has examined how ambient air respiratory toxins in U.S. public schools disproportionately affect children of Latino, Hispanic, and Asian descent.
The microplastics study adds another dimension to understanding how environmental factors may be contributing to chronic disease burden in the United States.
Limitations and Future Research Directions
The researchers emphasized that while their findings show concerning patterns, they do not yet prove a causal relationship between microplastics exposure and chronic disease. Further investigation is needed, particularly into the amount of time or level of exposure required to impact human health.
"The environment plays a very important role in our health, especially cardiovascular health," Ponnana noted. "As a result, taking care of our environment means taking care of ourselves."
Practical Implications
While completely avoiding microplastics exposure is nearly impossible given their widespread presence, the researchers suggest that limiting plastic production and ensuring proper disposal are the most effective ways to reduce exposure.
The findings were presented at the ACC meeting in Chicago and should be considered preliminary until published in a peer-reviewed journal. However, they provide compelling evidence for further research into the health impacts of microplastics and potential public health interventions to mitigate exposure.
