To be fair, those are large particles, which are neither as dangerous nor as persistent as smaller particles. Unless you’re allergic to them, of course.
PM2.5 is the really nasty carcinogenic stuff, but pollen size overlaps substantially with other forms of soot and IIRC is a double digit percentage of poor urban air quality. It’s somewhere around fourth or fifth largest source.
To be fair, those are large particles, which are neither as dangerous nor as persistent as smaller particles. Unless you’re allergic to them, of course.