<p>European Journal of Nutrition - Electronic supplementary material </p><p>Challenges to estimate validity of dietary acrylamide measurements.</p><p>Pietro Ferrari, Heinz Freisling, Eric J Duell, Rudolf Kaaks, Leila Lujan-Barroso, Françoise Clavel- Chapelon, Marie-Christine Boutron-Ruault, Laura Nailler, Silvia Polidoro, Amalia Mattiello, Domenico Palli, Rosario Tumino, Sara Grioni, Sven Knüppel, Anne Tjønneland, Anja Olsen, Kim Overvad, Philippos Orfanos, Michail Katsoulis, Antonia Trichopoulou, Jose Ramón Quirós, Eva Ardanaz, José María Huerta, Pilar Amiano Etxezarreta, María José Sánchez, Francesca Crowe, Kay- Tee Khaw, Nicholas J Wareham, Marga Ocke, Bas Bueno-de-Mesquita, Petra HM Peeters, Ulrika Ericson, Elisabet Wirfält, Göran Hallmans, Ingegerd Johansson, Dagrun Engeset, Geneviève Nicolas, Valentina Gallo, Teresa Norat, Elio Riboli, Nadia Slimani.</p><p>Pietro Ferrari (corresponding Author), Nutritional Epidemiology Group, International Agency for Research on Cancer, 150, cours Albert Thomas, 69372 Lyon Cedex 08, France; Tel +33(0)472738031, Fax +33(0)472738361; e-mail: [email protected]</p><p>Online Resource 1. Sample size in the EPIC acrylamide study, by smoking status and country.</p><p>Never smokers (n=255) Smokers (n=255) Country Men Women Men Women France - 15 - 15</p><p>Italy 15 15 15 15</p><p>Spain 15 15 15 15</p><p>UK 15 15 15 15</p><p>The Netherlands 15 15 15 15</p><p>Greece 15 15 15 15</p><p>Germany 15 15 15 15</p><p>Sweden 15 15 15 15</p><p>Denmark 15 15 15 15 Total 120 135 120 135</p>