Exposure to PM2.5 can cause ADHD and autism in children

Researchers have found a link between prenatal exposure to air pollution and disorders such as ADHD and autism.

Researchers at the IS Global Barcelona Institute for Global Health set out to examine the relationship between prenatal exposure to particulate matter and the size of the corpus callosum in children. 

The corpus callosum is a structure in the brain associated with attention deficit hyperactivity disorder (ADHD) and autism.

186 children from 40 different schools in Barcelona took part in the study, which you can read here.

The amount of fine particulate matter (PM2.5) that each mother and child were exposed to was calculated using data from the European Study of Cohorts of Air Pollution Effects and the residence history of each child.

Information about the children’s brain anatomy was obtained through magnetic resonance imaging, and behavioural data was collected using questionnaires completed by parents and teachers.

The researchers found that exposure to particulate matter, particularly in the last trimester of pregnancy can induce structural changes in the corpus callosum in children between the ages of 8 and 12 years. 

An increase of 7 μg/m3 in PM2.5 levels was associated with a nearly 5% decrease in the mean volume of the corpus callosum. 

Jordi Sunyer, leader of the study and head of the Childhood and Environment Programme at ISGlobal said: ‘Our findings are cause for concern for various reasons.’ 

‘First, in the cases of chronic parental exposure we studied, the PM2.5 levels were below the limit value established by the European Union.’ 

‘Second, the reduced volume of the corpus callosum is a common characteristic of ADHD and autism, a 5% reduction in the corpus callosum volume showed higher levels of hyperactivity.’ 

Marion Mortamis, the lead author of the study explained that the researchers chose to focus on pollution exposure during pregnancy: ‘Because brain structures are forming during this period and because the damage caused by exposure to high levels of pollution can be permanent.’ 

‘Knowing what brain damage occurs during the pregnancy could be very useful in predicting and treating behaviour problems that are often not diagnosed until later in childhood.’ 

In related news, new research has shown that a mother’s exposure to particulate matter during pregnancy is associated with reduced cardiac response to stress in 6-month-old infants. 

Photo Credit  – Pixabay