Definify.com

Webster 1828 Edition

pp.

Laid open; laid bare;uncovered; unprotected; made liable to attack; offered for sale; disclosed; made public; offered to view.

exposed

(usually followed by to) Vulnerable, susceptible.
exposed to abuse; exposed to danger‎
- 2014 April 21, “Subtle effects”, in The Economist, volume 411, number 8884:
  Manganism has been known about since the 19th century, when miners exposed to ores containing manganese, a silvery metal, began to totter, slur their speech and behave like someone inebriated. […] Nowadays workers are exposed to far lower doses and manganism is rare.

vulnerable, open to elements

exposed