In some coastal counties, a bathtub of ocean water holds 10 or more tiny plastic fragments, which researchers link to higher rates of chronic diseases like diabetes and stroke.
By Chloe Baul, Courthouse News Service
People who live in U.S. coastal communities near heavily polluted waters may face higher risks of Type 2 diabetes, stroke and coronary artery disease, according to researchers who analyzed ocean plastic levels and county health data.
The analysis focused on counties bordered by ocean waters with high concentrations of microplastics — tiny plastic particles that come from broken-down plastic waste like packaging, fabrics and personal care products.
This risk was higher compared to residents of coastal counties with low levels of microplastic pollution in nearby waters, according to new research published Wednesday in the Journal of the American Heart Association.
“This is one of the first large-scale studies to suggest that living near waters heavily polluted with microplastics may be linked to chronic health conditions. Plastic pollution is not just an environmental issue — it may also be a public health issue,” said Dr. Sarju Ganatra, senior author of the study and medical director of sustainability at Lahey Hospital & Medical Center in Massachusetts, in a press release.
Researchers sorted pollution levels into four categories based on average microplastic concentrations within 200 nautical miles of each county: low (less than 0.005 pieces per cubic meter), medium (up to 1 piece), high (1–10 pieces) and very high (more than 10 pieces).
To put that in perspective, researchers said very high levels could mean a bathtub-sized scoop of ocean water might contain 10 or more plastic fragments.
When comparing counties with very high versus very low microplastic pollution nearby, researchers found that residents in the most polluted areas had an 18% higher rate of Type 2 diabetes, a 7% higher rate of coronary artery disease and 9% more strokes.
Type 2 diabetes is known to double the risk of heart disease. Coronary artery disease, which involves plaque building up in heart arteries, can lead to heart attacks or strokes. Strokes, which occur when blood flow to the brain is blocked or interrupted, are a leading cause of death and disability.
Researchers say these conditions remained more common even after accounting for other factors like age, access to doctors, income and air quality.
“While this study measured pollution in ocean water, pollution isn’t limited to the sea,” Ganatra said. “Microplastics are everywhere: in drinking water, in the food we eat, especially seafood, and even in the air we breathe.”
The research included data from 152 coastal counties across the U.S., drawing on disease prevalence from the CDC and plastic concentration data from the National Centers for Environmental Information. Demographically, the counties had an average age of 43, with about half identifying as female and 75% as white adults.
Counties along the Gulf of Mexico and Atlantic coasts generally had higher levels of both pollution and disease compared to counties on the Pacific coast, the analysis found.
Researchers say the study’s design doesn’t prove microplastics directly cause health issues, but it does raise important questions for further investigation. They didn’t test residents for microplastic exposure, nor did they measure microplastics in fish or plants — only in nearby ocean water.
“We also didn’t measure plastic levels in residents of these counties, and we don’t yet know the exact ways these particles may harm the body. So, while the findings are compelling, they should be a call for more in-depth research, not for making definitive conclusions,” Ganatra said.
Still, he said the findings are reason enough to take the problem seriously.
“This study adds to a growing body of evidence that the garbage we discard into the environment often finds its way back to us. It’s time to shift from awareness to action,” he said. “We urge policymakers to view plastic pollution as an environmental crisis as well as a potential health crisis.”
