There is increasing evidence that exposures from the external environment are important factors in overall human health in a variety of diseases and disorders including Alzheimer's Disease-Related Dementia (ADRD). The NIH supports research on environmental risk factors (ERFs) for ADRD. This Notice of Funding Opportunity (NOFO) will support research projects that takethis research further by determining how exogenous ERFs affect ADRD disease mechanisms and phenotypic outcomes through innervated human surfaces. Exogenous ERFs include toxins and toxic chemicals, other pathogens, and other environmental exposures that reach innervated human surfaces. These surfaces include the gut, mouth, throat, lungs, nasal passages, skin and other surfaces that interface with the outside world. The scope of this NOFO includes mechanistic research relevant to ADRD to determine the effect(s) of exogenous ERFs at nervous system biological interfaces. Human studies (No Clinical Trials Allowed) to identify exogenous ERFs at these biological interfaces are also allowed if the mechanistic influence of these exposures is also included in the research plan. This initiative will require team science between neuroscientists that have deep expertise in ADRD research with experts in environmental science with knowledge of toxicity to the nervous system.