Fig. 1.
Experimental design. Rats were divided into low- (1.1 mg/m3) and high-dose (4.9 mg/m3) exposure groups; further divided into two subgroups, those exposed to either ZnONPs or HEPA-FA; and sacrificed at 1 day, 7 days, or 30 days after exposure for two weeks. ZnONPs: zinc oxide nanoparticles. HEPA-FA: high-efficiency particulate arresting (HEPA)-filtered air.