Feasibility of testing three salivary stress biomarkers in relation to naturalistic traffic noise exposure

Abstract

Background and objectives: Stress dependent alterations of the salivary biomarkers alpha-amylase (sAA), salivary chromogranin A (sCgA) and salivary cortisol (sC) have been reported in numerous studies recently. The aim of this pilot study was to investigate the feasibility of testing sAA, sCgA and sC in relation to naturalistic traffic noise exposure in order to monitor a direct stress response in a laboratory setup.

Methods: A total of twenty study participants were exposed to binaurally recorded naturalistic traffic noise samples containing 75 dB (L(A,)eq) for 20 minutes via a loudspeaker system. Saliva was collected directly before and after defined exposure to naturalistic traffic noise. Determination of sAA was performed enzymatically on a Hitachi 912 laboratory analyzer, sCgA was determined by ELISA technique and sC was determined using a RIA assay.

Results and conclusions: There was a significant increase of sAA and sC concentrations after traffic noise exposure (p=0.045; p=0.01), whereas for sCgA this was not observed (p=0.48). Measuring of sAA and sC appear to be feasible to investigate direct stress effects in relation to naturalistic traffic noise exposure in a laboratory setup. Considering the small sample size of this pilot study, these observations need to be further proved in a larger explorative study.