Saliva Cortisol
Saliva cortisol is
a noninvasive indicator of active free cortisol, a glucocorticoid
used as a biomarker of stress, and HPA axis activation.Our study found that common TRAP pollutant exposures
were associated with marked changes to saliva cortisol, indicating
that commuter exposures may impact acute stress responses, particularly
during the period of exposure, with effects subsiding shortly after
the exposure is reduced. In the present study, cortisol increased
in women in relation to some TRAP constituents, while men showed a
significant decline for several other TRAP constituents. Given the
time of the commute (morning), we would expect to see either constant
or declining cortisol levels in all participants across the period
of the commute, due to the decline following the cortisol awakening
response (CAR),