New research indicates that magnetite, a tiny particle found in air pollution, may trigger the development of Alzheimer’s disease, a debilitating form of dementia that affects millions worldwide.
Led by Associate Professors Cindy Gunawan and Kristine McGrath from the University of Technology Sydney (UTS), the study sheds light on the potential impact of air pollution on brain health. Published in Environment International, the study examined the effects of toxic air pollution particles on mice and human neuronal cells in the lab.
Associate Professor Gunawan emphasised the importance of understanding the environmental factors contributing to Alzheimer’s disease. While genetics play a role in less than 1% of cases, environmental and lifestyle factors are believed to be significant contributors to the disease’s development.
“This is the first study to look at whether the presence of magnetite particles in the brain can indeed lead to signs of Alzheimer’s,” she said.
The study focused on magnetite, a magnetic iron oxide compound commonly found in air pollution, particularly from vehicle exhaust, wood fires and industrial processes. Researchers exposed healthy and genetically predisposed mice to fine particles of iron, magnetite and diesel hydrocarbons over four months. They found that magnetite consistently induced Alzheimer’s-like pathologies, including neuronal cell loss and amyloid plaque formation, a hallmark of the disease.
Associate Professor McGrath explained how magnetite particles can enter the brain through inhalation, bypassing the blood-brain barrier and triggering inflammation and oxidative stress, both known contributors to dementia.
Dr Charlotte Fleming, co-first author of the study, highlighted that magnetite-induced neurodegeneration occurred independently of the disease state, with signs of Alzheimer’s observed in the brains of healthy mice.
The findings underscore the importance of reducing exposure to air pollution to mitigate the risk of neurodegenerative diseases like Alzheimer’s. Health practitioners and policymakers should consider implementing measures to improve air quality and reduce emissions from vehicles and industrial sources.
The study also suggests revising air pollution guidelines to include magnetite particles in safety thresholds for air quality indices, emphasising the need for stricter regulations to protect public health.
Ritchelle is a Content Producer for Healthcare Channel, Australia’s premier resource of information for healthcare.
