Smog, Aging Brains and Slient Strokes

Smog, Aging Brains and Slient StrokesThe May 2015 issue of “Stroke” contains results of a study indicating that nearness to major highways decreases brain volume and increases silent strokes. The California counties of Los Angeles, San Diego and Orange, among others, are apparently in deep trouble, brainwise.

The study focused on the effects of “particulate matter,” air pollution that is a mixture of solid particles and liquid droplets found in the air, which is smaller than 2.5 micrometers. Not surprisingly, major highways have high concentrations of particulate matter. Particulate matter pollution readily enters lungs and bloodstreams, causing a host of cardiovascular problems and lung problems, including but not limited to lung cancer.

Using 943 subjects over the age of 60, researchers used M.R.I. exams, information about the subjects’ closeness to major highways, and satellite data to measure particulate matter smaller than 2.5 micrometers.

Adjusting for other factors such as socioeconomic factors, lifestyle and health, researchers found that the subjects with the highest exposure to particulate matter had a 46% greater risk of “covert brain infarcts” or silent strokes. In addition, they found that each addition 2 micrograms/cubic meter is linked to decreases in cerebral brain volume equal to 1 year of natural aging.

Naturally, I went right to the ol’ “particulate matter” findings about California counties. According to the 2014 Report Card for California, assigning grades “A” for the best to “F” for the worst, the counties including Los Angeles, San Diego and Orange received an “F” for their particulate matter pollution. The Report Card can be accessed here:

This is particularly depressing, as California eventually made noble efforts to address the 1950’s smog-fest in its cities. Los Angeles, for example, reduced its ozone levels to 40% of its 1970’s levels, despite the fact that the city now has twice as many cars. Obviously, California has made some remarkable progress.

Particulate matter pollution, however, has increasingly concerned scientists because of its dire physical consequences. At least some experts assert that California must somehow create ways to move its people and products with zero emissions by 2030.

By Kathy Catanzarite

Source: Kathy Catanzarite – Staff Writer

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