The objective of this study was to observe the oxidative damage of lung tissue induced by formaldehyde in mice.The experimental mice were administrated with multiple doses of liquid formaldehyde with different concentrations by intratracheal medication.Subsequently,the mice were sacrificed,and their lung tissue were collected to determine the pulmonary surfactantassociated protein A(SP-A) content,superoxide dismutase(SOD) activity and malondialdehyde(MDA) content.Furthermore,the lung tissue sections were pr...