The researchers let 10 volunteers be exposed to the exhaust of a car inside a room, with its level of diesel exhaust similar to those in a typical busy street. They were asked to stay in the room for an hour while their brains were scanned using quantitative electroencephalography. The scanning continued even after they left the exposure room.
Similar measurements were repeated in conditions without the fumes. An increase in brain activity in the cortex began after 30 minutes of breathing fumes. This is the first time researchers have demonstrated a change in brain activity.
"We can only speculate what these effects may mean for the chronic exposure to air pollution encountered in busy cities where the levels of such soot particles can be very high," Lead researcher Paul Borm from Zuyd University has been quoted as saying.
According to Borm, "It is conceivable that the long-term effects of exposure to traffic nanoparticles may interfere with normal brain function and information processing. Further studies are necessary to explore this effect and to assess the relationship between the amount of exposure to particles and the brain's response, and investigate the clinical implications of these novel findings."
