(Reuters) — The closer a person lives to a source of pollution, like a traffic dense highway, the more likely they are to develop Alzheimer’s or dementia, according to a study by the University of Southern California (USC) that has linked a close connection to pollution and the diseases.
In a mobile lab, located just off of one of Los Angeles’ busiest freeways, USC scientists used a state-of-the-art pollution particle collector capable of gathering nano-sized particulate matter.
“We have shown that, as you would expect, the closer you get to the sources of these particles in our case the freeways, the higher the concentrations. So there is an exponential decay with distance. That means basically that, the concentration of where we are right now and if we were, let’s just say 20 or 10 or 50 yards from the freeway, those levels would be probably 10 times higher than where we are right now,” said USC Professor of Civil and Environmental Engineering, Costas Sioutas.
That means proximity to high concentrations of fossil fuel pollution, like a congested freeway, could be hazardous. Particulate matter roughly 30 times thinner than the width of a human hair, called PM2.5, is inhaled and can travel directly through the nose into the brain. Once there, the particles cause inflammatory responses and can result in the buildup of a type of plaque, which is thought to further the progression of Alzheimer’s.
“Our study brought in this new evidence and I would say probably so far the most convincing evidence that the particle may increase the risk of dementia,” said USC Associate Professor of Preventive Medicine, Jiu-Chiuan Chen. “This is really a public health problem. And I think the policy makers need to be aware of that, the public health risk associated with high level of PM2.5.”
USC researchers analyzed the data of more than 3,500 women who had the APOE4 gene, the major known risk-factor gene for Alzheimer’s disease. It showed that, over the course of a decade, the women who lived in a location with high levels of the PM2.5 pollution were 92 percent more likely to develop dementia.