Researchers at Tampere University in Finland have discovered a new immune response mechanism specific to exposure to nanoparticles. This mechanism is common to multiple species, from humans to simpler creatures, and it suggests that different species have adapted over time to this type of exposure. The findings of this study, published in the journal Nature Nanotechnology, have implications beyond the field of toxicology. They could help to explain why the COVID-19 pandemic had a more severe impact on people living in polluted areas, and they could also lead to new ways to predict the effects of chemical exposures on multiple species at a time. Nanotechnology is a rapidly growing field with many applications in biomedicine, energy, and climate change. However, there is a need to better understand the potential health and environmental effects of engineered nanomaterials. This research could help to address this need by providing new insights into how nanoparticles interact with the immune system.