Abstract:An investigation on the toxic effect of formaldehyde on bone marrow of male SPF level Kunming mice was conducted. After a 72h continuous and dynamic exposure to gaseous formaldehyde with three different concentrations (0.5mg/m3, 1.0mg/m3 and 3.0mg/m3, respectively), cell number at different phases of the cell cycle, DNA-protein crosslink (DPC), DNA stability and the expression profile of Nucleostemin and CYP1B1, two key factors in bone marrow cell differentiation were detected. The results indicated that formaldehyde exposure could cause DNA damage of bone marrow cell, with an obvious dose-response relationship between the DNA stability and DPC effect. Compared with the control group, the expression of Nucleostemin significantly increased in the 1.0mg/m3 group while it significantly decreased in the 0.5 and 3.0mg/m3 groups. The expression of CYP1B1 was also significantly different with that in the control group and the most obvious increase was found in the 1.0mg/m3 group. Thereby we conclude that mice exposed to formaldehyde can affect normal growth and metabolism of bone marrow cells.