Impact of Marine Microplastics on Neurologic and Functional Disabilities: A Population-Level Study

Background: Microplastics are emerging as environmental pollutants with potential neurotoxic effects, yet their association with neurological disabilities remains largely unexplored. Methods: In this cross-sectional study comprising 218 coastal counties in the United States, we compared the self-reported prevalence of cognitive disability, mobility disability, self-care disability, and independent living disability in counties with very high and low marine microplastic levels (MMLs). Unadjusted and adjusted prevalence ratios (PRs) were computed using population-weighted quasi-Poisson regression across three different models to examine the relationship between disability prevalence and MMLs. Results: Counties exposed to very high marine microplastic levels had a higher mean prevalence of self-reported cognitive disability (15.2% vs. 13.9%), mobility disability (14.1% vs. 12.3%), self-care disability (4.2% vs. 3.6%), and independent living disability (8.5% vs. 7.7%) compared to those exposed to low levels (p < 0.001). Regression analyses revealed significantly elevated adjusted prevalence ratios (PRs) for cognitive (PR: 1.09 [95% CI: 1.06–1.12], p < 0.001), mobility (PR: 1.06 [1.03–1.10], p < 0.001), self-care (PR: 1.16 [1.11–1.20], p < 0.001), and independent living disability (PR: 1.08 [1.05–1.12], p < 0.001) in counties with very high microplastic exposure compared to those with low exposure. Conclusions: This study highlights a significant association between marine microplastic pollution and the self-reported prevalence of cognitive, mobility, self-care, and independent living disabilities at the county level. While merely associative, these findings emphasize the urgent need for further investigation into the individual-level health impacts of microplastic exposure and underscore the importance of environmental interventions to mitigate potential risks.