The differences in air quality in large cities like New York City and smaller cities like anything else upstate is unbelievable. With upstate New York full of forestry, the pollution gets filtered out, helping the air stay so clean you can smell it. Living among this cleaner air is something everyone should stride toward, not only because it smells fresher, but also because it’s healthier in many ways. A new study from University of Montana now shows that it may even help us avoid brain damage and neurodegenerative disease.

Dr. Lilian Calderón-Garcidueñas, a professor at the university, found that heavily polluted cities are contributing to changes within the brain that may cause diseases like Parkinson’s or Alzheimer’s. As people breathe the polluted air, the particulate matter within, which includes various metals, passes through the brain’s usually protective blood brain barrier, as well as similar barriers in the gastrointestinal and respiratory systems. What’s worse is that these changes are occurring in children as young as 7.

As a result, these children’s bodies are producing antibodies that are destroying neural cells and the cells that make up these barriers, which can lead to further deterioration from foreign materials. “We asked why a clinically healthy kid is making autoantibodies against their own brain components,” Calderón-Garcidueñas said in a press release. “That is indicative of damage to barriers that keep antigens and neurotoxins away from the brain. Brain autoantibodies are one of the features in the brains of people who have neuroinflammatory diseases like multiple sclerosis (MS).”

The professor’s study involved 139 children living in either low-pollution cities or the highly polluted Mexico City. Each of the children underwent tests in which their serum and cerebrospinal fluid was tested for antibodies, metals, and other materials that would indicate oxidative stress, inflammation, and other immune responses. The researchers chose to study Mexico City because there has been a 400 percent increase in MS cases, which researchers say might be due to its high levels of pollution.

A little over 20 years ago, the United Nations recognized Mexico City as the most polluted city in the world. Other cities that made the list of highly polluted cities included Rio de Janeiro, New York City, Seoul, Shanghai, Tokyo, Bombay, and Los Angeles. Though the World Health Organization doesn’t consider any level of exposure to particulate matter safe, it has estimated that reducing particulate matter levels from 70 — the world average — to 20 micrograms per cubic meter could reduce air quality-related deaths by 15 percent.

In Mexico City, the government has been making a concerted effort to lower levels of air pollution. Just last year, it commissioned the construction of a new hospital building, called the Torre de Especialidades, as part of a $20 million health project. The building was made with a special kind of tile capable of filtering the polluted air through chemical reactions, and turning it into safer chemicals such as carbon dioxide and calcium nitrate.

As for Calderón-Garcidueñas’ study, she said the next step in this line of research is to determine through a longitudinal study whether a relationship between cognitive deficits and alterations in the brain, which have been seen through MRI scans before, are true. “Investing in defining the central nervous system pathology associated with exposure to air pollutants in children is of pressing importance for public health,” she said.

Source: Calderón-Garcidueñas LA, Vojdani A, Busch Y, et al. Air Pollution and Children: Neural and Tight Junction Antibodies and Combustion Metals, the Role of Barrier Breakdown and Brain Immunity in Neurodegeneration. Journal of Alzheimer’s Disease. 2014.