This research demonstrates that the presence of trace levels of contaminants to an otherwise evacuated system, leads to rapid onset of damage to optical elements in the presence of 1064 nm laser radiation. This onset is observed as a lifetime reduction. Specifically, 1064 nm radiation from a pulsed laser having approximately 800 mJ/cm2 average fluence (<1.5 J/cm2 peak fluence) illuminated fused silica windows used to seal a vacuum chamber, with a pressure <1.3x10-1 Pa (<1.0x10-3 torr). In the absence of any contamination the windows were demonstrated to show no signs of damage up to 2.3x106 laser pulses. When gas phase toluene was introduced into the system at varying concentrations (<1.3 x10-1 - 41Pa) (<1.0x10-3 - 3.1x10-1 torr), the onset of damage was seen to be a function of the toluene concentration, and damage was seen to occur as rapidly as 30,000 laser pulses. This phenomenon was also observed when the windows had a commercially applied coating of MgF2 on the surface in the vacuum system. Similar experiments using acetone as the contaminant led to no observed damage for either type of optic, even at high concentrations. However, experiments using commercial adhesives, commonly used in spacecraft construction, do provide evidence of lifetime reduction. A discussion of possible mechanisms leading to damage is also included but none has been established from this work.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.