Environmental public health risks in European metropolitan areas within the EURO-HEALTHY project by Mitsakou, C, Dimitroulopoulou, S, Heaviside, C, Katsouyanni, K, Samoli, E, Rodopoulou, S, Costa, C, Almendra, R, Santana, P, Dell'Olmo, M, Borell, C, Corman, D, Zengarini, N, Deboosere, P, Franke, C, Schweikart, J, Lustigova, M, Spyrou, C, De Hoogh, K, Fecht, D, Gulliver, J, Vardoulakis, S