Children who are exposed to outdoor air pollution during their first year of life are more likely to develop allergies to food, mold, pets and pests, according to a recent study.

Researchers at the University of British Columbia found that that the sensitivity to allergens was associated with exposure to traffic-related air pollution during infancy.

"With the increasing rates of allergies amongst children in Canada and elsewhere, we were interested in determining if air pollution from traffic might be partially responsible," Michael Brauer, the study's senior author, said in a statement. "This is the first study to find a link between air pollution and measured allergic sensitization during the first year."

For the study, researcher collected and analyzed data from more than 3,500 families and their infants across Canada who are being closely monitored to determine how genetic and wide range of environmental factors contribute to health outcomes, especially with regard to allergies and asthma.

They found that while infants exposed to air pollution were at greater risk, researchers did not find a link between mothers exposed to air pollution during pregnancy and allergy risk in their children. Vancouver had the largest proportion of children to develop sensitivity to allergens (23.5 per cent), compared to Toronto and Edmonton (17 per cent each), and Manitoba (9 per cent). The study also found that children who live with furry pets and no attached garage were more likely to have no sensitivity to allergens.

"Understanding which environmental exposures in early life affect the development of allergies can help tailor preventative measures for children," said Hind Sbihi, first author of the study. "We also found that children who attended daycare or with older siblings in the household were less likely to develop allergic sensitization, suggesting that exposure to other children can be protective."

The findings are detailed in the journal Environmental Health Perspectives.