I have discovered that de-natured alcohol will destroy Nalgene bottles, if stored in them for long periods- I have one that I kept full for a year and it weakened to the point where I crushed it with one hand. The material became so brittle that it basically shattered with little effort. I was on a 5 day hike when I noticed the lattice of fine cracks. Thankfully, it made it through the trip! Anyone else noticed this? (I will post a picture soon)