Overview of biological resources for the study of airborne pollutants

Airborne nanoparticles constitute a significant global health threat. To reduce animal testing and better replicate the exposure of humans to airborne pollutants, environmental toxicology relies on in vitro cell culture and advanced cell-supporting models and platforms. Traditional submerged cell cultures, using either primary cells or continuously-growing cell lines, have provided valuable insights into the toxicity of nanoparticles. However, they do not fully replicate the characteristics of chronic human exposure to airborne nanoparticles. Air-liquid interface (ALI) systems and three-dimensional (3D) cell cultures, including spheroids, organoids and organ-on-a-chip platforms, mimic more accurately in vivo tissue structure and organ functions. These advanced in vitro systems have a great potential to examine airborne pollution and to protect human health. Zebrafish ( Danio rerio ) embryos before the self-feeding larval stage provide a robust in vivo model used to examine, together with cell and tissue models, the harmful effects of airborne nanoparticles.