effect of acute noise exposure on salivary cortisol: a randomized controlled trial

cardiovascular adverse effects are interesting aspects of occupational noise exposure. one possible mechanism of these effects is an alternation in hypothalamic-pituitary-adrenal axis. our aim was to measure salivary cortisol response to relatively high-intensity noise exposure in a controlled randomized trial study. we exposed 50 male volunteers to 90 dba noise for 20 minutes and compared their level of salivary cortisol with 50 non-exposed controls. salivary samples obtained before and after exposure. before intervention means (sd) salivary cortisol level were 3.24 (0.47) ng/ml and 3.25 (0.41) ng/ml for exposed and non-exposed groups respectively. mean salivary cortisol level increased to 4.17 ng/mlafter intervention in exposure group. this increment was statistically significant ( p =0.00). mean salivary cortisol level of the non-exposed group had statistically non-significant decrement after this period (0.2 ng/ml). the difference between salivary cortisol level of non-exposed and exposed groups after the intervention was statistically significant. noise exposure may affect the hypothalamic-pituitary-adrenal axis activity, and this may be one of the mechanisms of noise exposure cardiovascular effects.