Air pollution data was integrated with existing longitudinal data from the Christchurch Health and Development Study (CHDS) which has followed more than 1200 children born in the city in 1977.
University of Otago Christchurch Health and Development Study principal scientist Prof Joseph Boden said a growing body of evidence supported an association between air pollution exposure and adverse mental health outcomes, especially in adulthood.
However, very little was known about the effects of air pollution exposure during childhood.
By tracking air pollution exposure from the prenatal period to the age of 10, and linking that data to subsequent cognitive and mental health outcomes, the study was able to highlight the long-term consequences of growing up in polluted environments, he said.
It found a wide range of cognitive, educational and mental health outcomes, including an increased risk of attention problems, conduct issues, lower educational attainment and substance abuse in adolescence for those associated with higher exposure.
"It’s a fairly unsupported hypothesis, but I think that mainly what we’re seeing in young people is a reaction to the fact that they economically, can expect to do less well than their parents or their grandparents before them."
He said the source of the air pollution was mainly from cars, open fires and industrial manufacturing, and he believed all 1200 people in the study were negatively affected to varying degrees.
"Using GPS mapping, we can understand where hot spots in particular areas are, so in certain neighbourhoods, the concentration [of pollution] was worse because perhaps they had a factory in it, for example, Woolston, so it would be worse for children there.
"But because it’s a common environmental background, everyone will be affected to a degree."
Prof Boden encouraged policymakers, educators and healthcare professionals to consider air pollution as a potential contributor to developmental challenges — not just a physical health concern.
"It would probably be a fairly complex suite of solutions.
"Some of them could have to do with air filtration, putting greater restrictions on how much pollution factories can put out, and a move to more electric vehicles and less coal-fired power generation."
The findings, alongside other contemporary evidence of air pollution’s harmful effects, underscored the importance of targeted interventions and policies to reduce exposure to air pollution, especially for children, he said.
