Cystic fibrosis is a genetic disease in which phenotypic variability is still poorly understood. Our hypothesis is that the exposome, and more specifically exposure to air pollution and/or anxiety, could play a role in this phenomenon. In this context, we have developed an experimental study in which cystic fibrosis mice were exposed to stress (anxiety) and then to complex realistic atmospheres. Our results should provide mechanistic elements for a better understanding of the phenotypic variability observed in cystic fibrosis patients and thus be able to propose new avenues for better management of these patients.