Longitudinal assessment of the intestinal microbiota of a birth cohort exposed to environmental pollutants during the perinatal period: Childhood and Environmental Pollutant Project (PIPA)

This study is part of the Childhood and Environmental Pollutant Project (PIPA). Environmental contamination by a wide variety of environmental pollutants can impact ecosystems, decrease environmental microbial diversity and alter the gastrointestinal tract-associated microbiota. However, the effect of exposure to environmental pollutants on the developing gut microbiota is still poorly investigated. This thesis aims to study the effect of exposure to environmental pollutants on the intestinal microbiota during the first six months of life, also investigating the relationship between maternal consumption of ultra-processed foods and pollutant levels in umbilical cord blood. The 16S rRNA gene was evaluated in meconium and feces samples from babies one, three and six months old and the infant microbiome was associated with metal concentrations (arsenic, cadmium, mercury and lead), perfluoroalkylated substances (PFAS) and pesticides measured in maternal blood and urine and in umbilical cord blood. Maternal consumption of ultra-processed foods was investigated using a food frequency questionnaire. The results indicate that the effect of pollutant exposure was greater when associated with early life stressors such as cesarean deliveries and preterm births compared to vaginally born babies.