Air pollution can be bad for children - starting even before birth, a new study suggests. Researchers studied exposure to polycyclic aromatic hydrocarbons, or PAHs, a form of pollution caused by burning gasoline, diesel fuel, home heating oil and coal. They found that prenatal exposure to these compounds was tied to changes in the structure of an offspring’s brains and to intellectual deficits and behavioural problems in childhood.
The researchers measured PAH concentrations in the air and in the blood and urine of 40 mothers in their third trimester of pregnancy, as well as in their children’s urine. They followed the children until they were seven to nine years old, performing magnetic resonance imaging tests on their brains. The results are in JAMA Psychiatry.
The higher the exposure to PAHs, the more reductions the children had in the white matter surface of the left hemispheres of their brains. The amount of damaged white matter correlated directly with higher scores on measures of symptoms of attention deficit hyperactivity disorder and other behavioural problems.
Higher exposure to PAHs and white matter deterioration were also associated with lower scores on tests of processing speed, the ability to take in new information and respond to it. “Everyone is exposed to these compounds,” said the lead author, Dr Bradley S Peterson, the director of the Institute for the Developing Mind at Children’s Hospital Los Angeles. “Pregnant women and young children are very vulnerable to environmental insults to the developing brain, and these exposures are likely having devastating effects.”
