The Exposome concept

The Exposome encompasses lifetime environmental exposures from the prenatal period onwards.3 Although sometimes limited to exposures that can be assessed through biomarkers (the ‘internal Exposome)’, the Exposome should consider all exposures regardless of their most relevant mode of assessment, including lifestyle factors and factors assessed through questionnaires, environmental measurements and models. Consequently, this notion extends beyond the borders of molecular epidemiology. A first embodiment of the Exposome concept is the literature on biomonitoring, which provides a description of the levels of biomarkers of exposures to as many as several hundred environmental contaminants in population samples from some areas of the world, as illustrated in the National Health and Nutrition Examination Survey (NHANES) in the USA.4 This research vein can allow identifying patterns of co-varying exposures or behaviours, as is already carried out in dietary studies with the grouping of individuals sharing specific dietary patterns (eg, Mediterranean diet or fast-food type eating behaviours). It offers the perspective of identification of population subgroups simultaneously exposed to numerous adverse exposures, and of studying if these correlate with sociodemographic factors; to this extent, this research vein is connected to the issue of environmental equity,5 in which the focus is …