Asthma is the most common chronic disease in childhood. Long term studies indicate predisposition to asthma develops in the first three to five years of life. Recent evidence suggests exposure to air pollution from traffic is associated with new cases of asthma. However, the long-term impacts of air pollution exposure and whether this exposure causes asthma are unclear. Nina Clark is investigating the association between exposure to air pollutants and childhood respiratory diseases in southwestern BC. Using the BC Linked Health Database that connects various data sources to provide individual level health outcome data, Clark is tracking the exposure and health outcomes of approximately 120,000 children who were born in the region over the four-year period beginning in 1999. She will examine resources including maps detailing air pollution concentration, medical services plan billing records and hospital discharge records. Clark will also look at variables such as age, gender, birth weight and socioeconomic status. She hopes her research will lead to targeted reductions of air pollution exposure, such as zoning or land use restrictions to limit exposure of children, and help provide focus for future interventions and policies.