Air pollution is a major environmental risk factor for health and has been linked to a wide range of adverse health outcomes in adults, including cardiovascular disease and metabolic syndrome. Associations with metabolic syndrome risk were examined using multivariable regression models, and metabolic syndrome risk was calculated using a previously validated score based on waist circumference, blood pressure, blood lipids and insulin levels, following International Diabetes Federation criteria. Conversely, no associations were found between exposure on commuting routes and metabolic syndrome risk. “Our results reinforce the need to continue reducing air pollution levels to protect children’s cardiometabolic health.” McEachan, Bente Oftedal, Euripides G. Stephanou, John Wright, Wen Lun Yuan, Martine Vrijheid, Childhood outdoor air pollution exposure across multiple microenvironments and metabolic syndrome: A HELIX cohort analysis, Environmental Research, https://doi.org/10.1016/j.envres.2026.124892.