Personal exposure to ultrafine particles among Spanish schoolchildren according to type of environment. Preliminary results.

Introduction: Ultrafine particles (UFPs) are the airborne particulate matter of less than 0.1 µm in size. Since personal exposure to UFP and its health-related effects in children are still to be well described, we aim to assess personal exposure in different environments among schoolchildren from a Spanish cohort. Method: The study population consists of 71 children from 10 to 11 years old. For each child, personal exposure to UFP was measured continuously over 24 hours in consecutive school-days: (i) a field technician took a small backpack equipped with a UFP active sampler (DISCmini) to the child’s home and instructed him/her to carry the backpack for the following 24 hours; (ii) the child performs health examinations and parents answer questionnaires about time-activity patterns, socio-demographic factors and other exposures. Median UPF exposure levels were obtained for the global period and for different types of environment: school, home, active transport (walking or cycling) or passive transport (...