Aluminium in the Human Brain: Routes of Penetration, Toxicity, and Resulting Complications

Aluminium (Al) is the most ubiquitous metal in the Earth's crust. Even though its toxicity is well-documented, the role of Al in the pathogenesis of several neurological diseases remains debatable. To establish the basic framework for future studies, we review literature reports on Al toxicokinetics and its role in Alzheimer's disease (AD), autism spectrum disorder (ASD), alcohol use disorder (AUD), multiple sclerosis (MS), Parkinson's disease (PD), and dialysis encephalopathy (DE) from 1976 to 2022. Despite poor absorption via mucosa, the biggest amount of Al comes with food, drinking water, and inhalation. Vaccines introduce negligible amounts of Al, while the data on skin absorption (which might be linked with carcinogenesis) is limited and requires further investigation. In the above-mentioned diseases, the literature shows excessive Al accumulation in the central nervous system (AD, AUD, MS, PD, DE) and epidemiological links between greater Al exposition and their increased prevalence (AD, PD, DE). Moreover, the literature suggests that Al has the potential as a marker of disease (AD, PD) and beneficial results of Al chelator use (such as cognitive improvement in AD, AUD, MS, and DE cases).

Automated summary

Aluminium (Al) is widely present in the Earth's crust and its role in the pathogenesis of neurological diseases is still debated. This review examines Al toxicokinetics and its involvement in several diseases, including Alzheimer's disease, autism spectrum disorder, alcohol use disorder, multiple sclerosis, Parkinson's disease, and dialysis encephalopathy. The literature suggests excessive Al accumulation in the central nervous system in these diseases, as well as epidemiological links between Al exposure and increased disease prevalence. Al also shows potential as a disease marker and the use of Al chelators has beneficial effects in some cases.