The Collaborative International Dictionary of English v.0.48:

Imperilment \Im*per"il*ment\, n.
   The act of imperiling, or the state of being imperiled.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

26 Moby Thesaurus words for "imperilment":
   breakers ahead, cardhouse, cause for alarm, crisis, danger,
   dangerous ground, emergency, endangerment, gaping chasm,
   gathering clouds, hazard, house of cards, jeopardy, menace, pass,
   peril, pinch, plight, predicament, quicksand, risk, rocks ahead,
   storm clouds, strait, thin ice, threat