Particle size distributions of OPFRs were studied in outdoor settings.
The most abundant OPFR at both study sites was TBEP.
The abundances of OPFRs in coarse and fine particles were roughly equal.
Dry and wet deposition fluxes of particle-bound OPFRs were size-dependent.
Inhalation exposure risk to particle-bound OPFRs at both sites was low.