Wednesday, June 04, 2008

SIGG thermal question

I received an interesting question about SIGGs via email today:

Are there any health concerns with pouring boiling water into Sigg bottles to make tea and then letting it are cool and placing it in the refrigerator or freezer to cool it off?

My answer:

This report: http://lib.store.yahoo.net/lib/yhst-23192477770352/bpareport.pdf verifies that SIGGs do not leach BPA at higher temperatures. I have seen no anecdotal or empirical evidence that SIGG bottles cause ill health effects with high temperature contents.


However, there is a chance that the thermal shock of putting boiling water in a bottle and then transferring to the freezer could cause separation between the weld that holds the mouthpiece to the bottle. SIGG recommends not fully freezing bottles for this reason, although I have done this by accident once or twice with no damage to the bottle.

1 comment:

Alex said...

Also it should be pointed out that SIGG bottles seal very well. I have experienced this quality several times with tiny pressure releases during and after airline travel. If you pour boiling liquid into a SIGG, and then tighten the cap onto it, there is a chance you could collapse the bottle due to the pressure decrease with no intake created in the bottle. The Universal Gas Law (PV=nRT) is an amazing and powerful thing...