Car exhaust might be damaging our brains
Tuesday, November 8, 2011 at 01:34PM 
Breathing traffic exhaust for just 30 minutes can cause changes in the area of the brain associated with behaviour, personality and decision making, according to research reported in the Wall Street Journal.
Car exhaust is known to be linked to respiratory ailments like asthma, as well as to heart disease and cancers. It shouldn't come as a surprise that it is also linked to brain function—it could make us dumber and more prone to anti-social behaviour.
A report in the Wall Street Journal reviews recent research into the impact of traffic fumes on the brain, and the picture is grim.
A Columbia University researcher, Frederica Perera, has studied the link between exposure to pollutants in the womb and subsequent developmental problems in the children when they are born. Dr. Perera discovered a biochemical mark in the DNA of about half of the infants, left by prenatal exposure to high levels of polycyclic aromatic hydrocarbons in exhaust.
By age 5, the children with the mark in their genes averaged about four points lower on standard intelligence tests than those of less exposed children. By age 7, the children were more likely to show symptoms of anxiety, depression and attention problems.
Previous research has shown that heavy metals like lead and arsenic in the mother's blood and bones can cross to a developing fetus's brain and cause permanent damage, but researchers into traffic fumes are still searching for answers. The article states that research and laboratory tests suggest that "at every stage of life" traffic fumes have a "measurable" toll on mental capacity, intelligence, and emotional stability.
Even though cars and trucks today emit far less pollution than they did several decades ago, there are more of them today, and cities like Toronto are congested, with commuters spending longer times surrounded by exhaust fumes. In the worst cities in the US, drivers spend up to 140 hours annually idling in traffic. This is as long as an average person spends in a month at the office.
How does all that exhaust affect the brain? Studies have shown that just 30 minutes' exposure to street-level fumes causes intensified electrical activity in the brain region responsible for behaviour, personality and decision making. The changes suggest that stress is occurring. Could this be contributing to road rage? Are people losing it because of the fumes?
It's not such a far-fetched conclusion. Some researchers have found that breathing city air heavy with traffic exhaust for 90 days can change genetic activity in the elderly and the newborn.
Researchers in cities from New York to Beijing to Krakow have found that children who live in areas with high levels of emissions, on average, scored more poorly on intelligence tests and were more prone to depression, anxiety and attention problems than children growing up in cleaner air. Older people in the same environments suffered memory and reasoning problems. There is the serious possibility that emissions could heighten the risk of Alzheimer's and Parkinson's disease.
One study published this year showed that children born to mothers living within 1,000 feet of a major road or freeway were twice as likely to have autism. The result was independent of gender, ethnicity and education level, as well as maternal age, exposure to tobacco smoke or other factors.
The results of the research are worrisome, but as of now, scientists are careful to say, no one knows for certain whether breathing traffic fumes has a lasting effect on brain biology or behaviour. "But we ought to proceed with caution."
Reprinted with permission from Condo.ca
Reader Comments (1)
I never thought of that. That's why people right now are not doing right. Thanks for sharing this information.