WP1 aims to integrate epidemiology and human biomonitoring studies with the endocrine disruptor test systems for metabolic disorders, in order to increase the relevance of the endocrine disruptor test system. Various time windows will be considered, including developmental periods of high susceptibility (pregnancy-childhood-adolescence) and adulthood. This WP draws on large-scale, population-based study populations including ongoing human biomonitoring studies and some of Europe’s most informative prospective birth cohorts.