Léa Maitre, Jeroen de Bont, Maribel Casas,Oliver Robinson, Gunn Marit Aasvang, Lydiane Agier, Sandra Andrušaitytė, Ferran Ballester, Xavier Basagaña, Eva Borràs, Céline Brochot, Mariona Bustamante, Angel Carracedo, Montserrat de Castro, Audrius Dedele, David Donaire-Gonzalez, Xavier Estivill, Jorunn Evandt, Serena Fossati, Lise Giorgis-Allemand, Juan R Gonzalez, Berit Granum, Regina Grazuleviciene, Kristine Bjerve Gützkow, Line Småstuen Haug, Carles Hernandez-Ferrer, Barbara Heude,Jesus Ibarluzea, Jordi Julvez, J Marianna Karachaliou, Hector C Keun, Norun Hjertager Krog, Chung-Ho E Lau, Vasiliki Leventakou, Sarah Lyon-Caen, Cyntia Manzano, Dan Mason, Rosemary McEachan, Helle Margrete Meltzer, Inga Petraviciene, Joane Quentin, Theano Roumeliotaki, Eduard Sabido, Pierre-Jean Saulnier, Alexandros P Siskos, Valérie Siroux, Jordi Sunyer, Ibon Tamayo, Jose Urquiza, Marina Vafeiadi, Diana van Gent, Marta Vives, Dagmar Waiblinger, Charline Warembourg, Leda Chatzi, Muireann Coen, Peter van den Hazel, Mark J Nieuwenhuijsen, Rémy Slama, Cathrine Thomsen, John Wright, Martine Vrijheid
Purpose
Essential to exposome research is the collection of data on many environmental exposures from different domains in the same subjects. The aim of the Human Early Life Exposome (HELIX) study was to measure and describe multiple environmental exposures during early life (pregnancy and childhood) in a prospective cohort and associate these exposures with molecular omics signatures and child health outcomes. Here, we describe recruitment, measurements available and baseline data of the HELIX study populations.
Participants
The HELIX study represents a collaborative project across six established and ongoing longitudinal population-based birth cohort studies in six European countries (France, Greece, Lithuania, Norway, Spain and the UK). HELIX used a multilevel study design with the entire study population totalling 31 472 mother-child pairs, recruited during pregnancy, in the six existing cohorts
(first level); a subcohort of 1301 mother-child pairs where biomarkers, omics signatures and child health outcomes were measured at age 6–11 years (second level) and repeat-sampling panel studies with around 150 children and 150 pregnant women aimed at collecting personal exposure data (third level).
Findings to date
Cohort data include urban environment, hazardous substances and lifestyle-related exposures for women during pregnancy and their offspring from birth until 6–11 years. Common, standardised protocols were used to collect biological samples, measure exposure biomarkers and omics signatures and assess child health across the six cohorts. Baseline data of the cohort show substantial variation in health outcomes and determinants between the six countries, for example, in family affluence levels, tobacco smoking, physical activity, dietary habits and prevalence of childhood obesity, asthma, allergies and attention deficit hyperactivity disorder.
Future plans
HELIX study results will inform on the early life exposome and its association with molecular omics signatures and child health outcomes. Cohort data are accessible for future research involving researchers external to the project.