How Air Pollution Changes Our Decisions

New research shows how air pollution could alter our choices for the worse.

Posted Oct 29, 2019 | Reviewed by Kaja Perina

jcomp / Freepik
Source: jcomp / Freepik

Increased risks of general cognitive dysfunction and dementia are of real concern. However, we’re now learning that air pollution may affect our brains long before we reach adulthood, damaging higher-order thinking and compromising decision-making abilities. 

Some of the most striking evidence for this idea is data showing that air pollution exposure before birth could harm brain development and decision-making. This was demonstrated in a 2018 trial that looked at neuroimaging and cognitive function tests in children aged 6-10, as well as air pollution levels while these children were in utero.

The study found that those children with more air pollution exposure during the fetal period had areas of thinner cerebral cortex compared to those with less exposure. Equally important, those children with more exposure showed impaired inhibitory control on testing, which was linked to the thinner areas in their brains.

There’s similar research showing that exposure to air pollution in the 5th and 6th years of life is inversely related to working memory and that higher traffic-related air pollution is linked to slower childhood gains in working memory.

What might this mean on a practical level? Executive function, which includes inhibitory control and working memory, is essential to make calculated, long-term-oriented decisions. Healthy executive functions in children predict better physical health, lower levels of substance dependence and fewer criminal offenses in adulthood. If air pollution damages our executive functions, it could render us more impulsive and more likely to make poor choices. Unfortunately, there’s evidence that this is already taking place.  

In 2018, a trial looked at air pollution exposure and rates of adolescent delinquent behavior, finding that more exposure was significantly linked to increased delinquent conduct like lying, vandalism, and stealing. It gets worse in adults, with multiple studies showing that elevated levels of air pollution predict violent crime occurrences.

For example, a 2019 trial looked at levels of air pollution over almost the entirety of the United States. Researchers in this study then compared this data to rates of crime from an FBI database and found that violent crime rates were significantly increased when there were higher levels of air pollution. Strikingly, they saw that this result was “driven entirely by increases in assaults, which are indicative of impulsive and aggressive behavior,” meshing perfectly with the idea that our higher-level thinking is compromised by air pollution.

Let’s put all of this together. It’s no secret that air pollution is bad for our health, and we’re now learning that it has major, negative effects on our brains. On this subject, research to date has primarily focused on the long-term impacts on cognition and risk for dementia. However, it’s becoming clear that air pollution may actually alter our thinking much earlier on, changing our decisions so we are more likely to make impulsive, poor choices.

With this in mind, it becomes increasingly important that we do what we can to lower our personal exposure and our contribution to air pollution. At a very basic level, try to avoid inhaling air pollution when you can. This means doing your best to stay away from second-hand smoke as well as wood fire smoke when possible. If you live somewhere with intermittently high air pollution and have flexibility in your routine, check local air quality advisories before you spend considerable time outdoors. Avoiding rush hour and busy highways can help if feasible. Consider installing a high-efficiency particulate (HEPA) filter in your home. Finally, you can help decrease air pollution levels by commuting using carpools, public transport, biking or walking.