From particulates to pathways: environmental exposures and their impact on Alzheimer's disease.

Alzheimer's disease (AD) is a leading cause of cognitive decline and mortality, with its neurobiological mechanisms and etiology still not fully understood. Emerging evidence highlights the significant role of environmental pollutants in AD onset and progression. This review examines the impact of environmental compartments-air, water, soil, and pollutants-on AD pathology. Prolonged exposure to particulate matter (PM_2.5), heavy metals (lead, cadmium, mercury, arsenic), and engineered nanomaterials (silver, iron oxide, silica) increases AD risk. Additional factors like obesity, smoking, infections, cardiovascular diseases, diabetes, and electromagnetic fields may exacerbate AD. These exposures potentially drive key pathological features such as amyloid-β plaque deposition and tau protein aggregation. By analyzing recent studies, this review highlights the intersection between environmental exposure and AD progression, emphasizing how such factors can accelerate the disease. It provides practical guidelines to mitigate these risks, aiming to reduce AD incidence while advancing understanding of its environmental contributions.