Also called PM10s or dust, have a diameter between 1 x 10^-5 m and 2.5 x 10^-6 m, contain many thousands of atoms
Fine particles
Also called PM2.5, have a diameter between 100 and 2500 nanometres (1 x 10^-7 m to 2.5 x 10^-6 m), contain several thousand atoms
Nanoparticles
Have a diameter between 1 and 100 nanometres, only contain a few hundred atoms
As particle size decreases by 10 times, the surface area to volume ratio increases by 10 times
Nanoparticles can potentially be absorbed into the body and enter cells, but the long-term effects are unknown, so they must be studied and used carefully
