Canadian researchers have demonstrated for the first time that acute exposure to traffic pollution can immediately impair human brain function, providing unique evidence for a relationship between air quality and cognition. Adults were exposed to diesel smoke before imaging brain activity with an fMRI machine.
Air pollution in urban environments has long been associated with poor cardiovascular, respiratory, and brain health. But connecting the dots between air quality and human health has been difficult for researchers. Other than associating the incidence of specific diseases in highly polluted areas, it is difficult to accurately quantify an individual’s exposure to air pollution.
Many cell and animal studies can demonstrate how air pollution affects living organisms. However, as we know, there is often a wide gap between the effects of toxins on mice in the laboratory and chronic exposures to humans in the real world.
So perhaps the final missing piece of the puzzle for the researchers was a direct human exposure study. That’s not strictly ethical.
This new study used a model of human exposure to diesel exhaust that was developed over a decade ago. This technology provides controlled and diluted concentrations of diesel exhaust particulate matter to human subjects at levels considered representative of real-world exposure but proven to be safe. In the laboratory, 25 healthy adults were exposed to either diesel exhaust or filtered air for 2 hours of her, and her brain activity was measured using fMRI before and after each exposure. I was.
The primary focus of this research was the impact of this type of traffic-related air pollution on what is known as the Default Mode Network (DMN). It is a series of interconnected cortical brain regions that play important roles in cognition, memory and emotion.
Findings suggest that brief exposure to diesel exhaust caused a decrease in DMN activity compared to that seen when subjects were exposed to filtered air, suggesting that functional connectivity between different brain regions could be affected. This type of DMN change is associated with depression and cognitive decline, said Jodie Gawryluk, lead author of the study.
“We know that altered functional connectivity in the DMN is associated with cognitive decline and symptoms of depression, so it’s worrisome that these same networks are disrupted by traffic pollution,” Gawryluk said. said. “More research is needed to fully understand the impact of these changes on function, but they can impair people’s ability to think and work.”
These new discoveries alone do not make much sense. This study did not evaluate to suggest that the observed changes in the DMN affected cognition. Along with this, these findings may become even more important. They effectively demonstrate the severe effects of air pollution on the human brain in an unprecedented way.
According to senior author Chris Carlsten of the study, it’s unclear what long-term effects exposure to this type of pollutant might have on the human brain. On the positive side, the researchers found that DMN brain activity returned to normal relatively quickly after exposure to diesel fumes. Carsten can therefore only hypothesize what the effects of more chronic, continued exposure might be.
Carlsten says: “It’s important to make sure your car’s air filter is working properly. If you’re walking or biking on a busy street, consider detouring to a less-trafficked route. Please give me.”
This research Environmental hygiene.
Source: University of British Columbia
