Marine Microplastic Pollution and Neurologic Disability: What’s the Link?

Compared with coastal counties in the United States with low levels of marine microplastics, those with very high levels have higher rates of multiple disability, according to study results to be presented at the 2025 American Academy of Neurology (AAN) annual meeting, held from April 5 to 9, 2025, in San Diego, California.

Mounting evidence suggests that micro- and nanoplastics contribute to cognitive decline. Pollution with micro- and nanoplastics can come in multiple forms, including in marine environments. It remains unclear whether marine microplastic levels contribute to cognitive decline and/or disability.

In this cross-sectional study, researchers from Lahey Hospital & Medical Center sourced data from 218 coastal counties in the US. The researchers compared the prevalence of cognitive, independent living, mobility, and self-care disabilities between counties that had very high and low marine microplastic levels.

The coastal counties with very high marine microplastic levels had higher rates of cognitive (15.2% vs 13.9%; P <.001), mobility (14.1% vs 12.3%; P <.001), independent living (8.5% vs 7.7%; P <.001), and self-care (4.2% vs 3.6%; P <.001) disabilities than the counties with low marine microplastic levels, respectively.

In the adjusted analyses, compared with counties with low marine microplastic levels, those with very high levels were associated with greater rates of self-care disability (adjusted prevalence rate [aPR], 1.16; 95% CI, 1.11-1.20; P <.001), cognitive disability (aPR, 1.09; 95% CI, 1.06-1.12; P <.001), independent living disability (aPR, 1.08; 95% CI, 1.05-1.12; P <.001), and mobility disability (aPR, 1.06; 95% CI, 1.03-1.10; P <.001).

This study may have been limited by only including data from a single timepoint. Additional study is needed to assess temporal trends in the relationship between marine microplastic levels and disability.

“Our findings indicate a significant association between marine microplastic levels and the prevalence of cognitive, mobility, self-care, and independent living disability in the US coastal counties. Further research is warranted to explore the potential public health implications of microplastic pollution,” the researchers concluded.