effects of simultaneous formaldehyde vapor and noise exposure on pituitary-gonadal axis in adult male mice

background: formaldehyde (h2c = o), is a member of aldehyde family with a simplest organic molecule, used in various industries. the aim of this experimental study was to investigate the effects of simultaneous formaldehyde and noise exposure on hormonal pituitary-gonadal axis in adult male mice. methods: 46 adult male mice were randomly assigned to one control group and three experimental groups which were exposed to formaldehyde vapor (10 ppm) (f), noise (100 db) (n), and simultaneous formaldehyde with noise (nf), respectively for 10 days (8 hours a day). at the end of the experiment half of the mice of each group were sacrificed 24 hours after exposure (short-term effects) and the rest were sacrificed 35 days after the end of exposure (long-term effects). plasma concentrations of testosterone, lh, fsh were measured using the elisa method. results: in short-term analysis, the serum testosterone in groups n, f, and nf were 2.73±0.24, 2.58±0.16, and 2.03±0.22,(ng/ml)respectively which had a significant decrease (p<0.001)compared to control group(3.82±0.35). the lh level in groups f, and nf also showed significant reduction compared to control group (p<0.05 and p<0.001). conclusion: reduction of serum testosterone and lh level may be potentiated by noise (700-5700 hz) in the simultaneous exposure to formaldehyde and noise.