Pollen particles are quite fragile and tend to break up into PM2.5 and smaller, especially during rain events. See for instance the reference below. https://do

Pollen particles are quite fragile and tend to break up into PM2.5 and smaller, especially during rain events. See for instance the reference below. https://doi.org/10.1016/j.aeaoa.2022.100177 https://doi.org/10.1016/j.aeaoa.2022.100177