The invention relates to novel microemulsions comprising a non-polar lipid, at least one polar solvent, a surfactant, and a polar lipid. A microemulsion of these ingredients provides an environment that substantially encloses airborne particles, and it can be used for entrapping such particles. The inventive microemulsions are especially adapted for the prevention of symptoms in mammals, which are indirectly or directly caused by airborne particles. The invention further provides compositions comprising such microemulsions and methods of treatment comprising administering the same.