Long-Term Industrial Emissions Exposure and Cognitive Impairment in Older U.S. Adults: A Longitudinal Cohort Study.

BACKGROUND: The demographic shift toward an older global population is increasing the burden of Alzheimer's Disease and Related Dementias (ADRD). While age is the strongest risk factor, environmental toxicants are increasingly recognized as contributors to cognitive decline. Plastics and rubber manufacturing facilities emit neurotoxic chemicals, yet their relationship to ADRD risk remains understudied. This study assesses whether exposure to plastics/rubber industry emissions is associated with ADRD risk and whether sociodemographic factors influence this relationship. METHODS: We linked geocoded Environmental Protection Agency (EPA) Toxic Release Inventory (TRI) data with Panel Study of Income Dynamics (PSID) records and Neighborhood Change Database (NCDB) Census data. Historical exposure to plastics/rubber emissions and time-varying sociodemographic characteristics were measured from 1990 to 2017, leveraging PSID's longitudinal structure to capture residential mobility. ADRD risk was defined as a positive AD8 screen (≥ 2 endorsed cognitive challenges) in 2017, 2019, 2021, or 2023. Logistic regression models estimated ADRD risk as a function of average total pounds of chemicals released from the nearest TRI facility to each individual's census tract of residence over time, adjusting for individual and neighborhood characteristics. RESULTS: Moderate emissions exposure was significantly associated with elevated ADRD risk (OR = 1.34), independent of income and neighborhood disadvantage. Neighborhood disadvantage was also strongly predictive of ADRD risk. CONCLUSIONS: Environmental emissions may represent a modifiable risk factor for ADRD and contribute to disparities in cognitive aging.