On top of respiratory and cardiovascular problems...Yesterday, I wrote about how a minority of cars are causing about 90% of air pollution from vehicles. We all know that dirty air is a killer, attacking your respiratory system and your heart. But more evidence is piling up that it's also bad for your mental health.
A study of 70,000 women between the ages of 57 and 85 shows that there's a significant link between exposure to air pollution and anxiety. The researchers used current and previous addresses of the participants in the study to estimate exposure to air pollution (for example, someone living close to a highway or an industrial park). The culprit seems to be small particles, which can travel deeper in our lungs, not large ones; women who were exposed to them one month before their anxiety test were about 12% more likely to have high anxiety symptoms compared to the women estimated to be exposed to the least particles one month previously.
Keep in mind, all that has been established at this point is correlation. The women who are more exposed to small particle air pollution are more at risk of experiencing anxiety issues. More research will be required to figure out if there's a causality there, or if maybe there are other factors, like for example that more polluted areas are more stressful to live in (almost assuredly up to a point, but maybe it doesn't explain all of the difference). It will also be interesting to conduct research on other groups (younger people, men) to see how they are impacted.
Chances are it will be a mix of things, though none of that would remove all the other health benefits of reducing air pollution. Reduced anxiety might just be one more benefit.