Exposure to physical and psychosocial hazards
may affect psychological as well as
physical health. The evidence suggests
that such effects on health may be mediated
by, at least, two processes: a direct
physical mechanism, and a psychological
stress-mediated mechanism. These two
mechanisms do not offer alternative explanations
of the hazard-health association;
in most hazardous situations both operate
and interact to varying extents and in various
ways.