The Bear Grylls Canteen Kit is one of many products that Bear has release in conjunction with Gerber Gear. This kit is a bit more high-tech than canteens that have been used through history.
Archeologists believe that canteens have been around in one form or another for about 60,000 years. The fact that man can not survive much more than 3 days without water suggests to me that they've been around a lot longer than that.
Canteens have been made out of many materials. Some of the earliest were actually ostrich eggs with a small hole in the top that the water carrier wove a basket around. If you watch the show Dual Survival you've seen one of the guys actually use this trick to carry water.
As technology grew, gourds and leather bags used as canteens were replaced by glass. Once tin and aluminum arrived on the manufacturing scene these materials replaced glass canteens.
All of these have their different sets of problems when you make canteens out of them. Eggs and gourds break easily, leather bags can develop leaks and get dry and crack if not taken care of, glass shatters and metal dents when banged around and develops pinhole sized leaks.
Finally, along came Dow Chemicals and Ethocel. Ethocel was Dow's first plastic and it was ready to be used in the WWII war effort. There were a myriad of uses for this plastic which included, of course, canteens. Since then modern canteens have been made almost exclusively out of plastic.
Technology moves at a rapid pace and although the canteens of today look the same as their ancestors their promotions make them a breed apart.
Most modern canteens are “BPA free” which means that they are free of “Bisphenol A”. It's probably a good thing to have a BPA free water bottle. From the reports I read, the problem areose from people using plastic baby bottles and heating them up which released the BPA and was ingested by the baby.
So the question to ask is: If you're out in the desert and your walking with a hot canteen that is not “BPA free” are you ingesting BPA? To be honest, I do not know the answer to that question but “BPA free” canteens are easy to get so why take the chance?
This rings us full circle to the latest canteen offering by Bear Grylls and Gerber. They attempted to create a high-tech canteen and cash in on the recent survival / prepper wave. Although they did a good job in some of the important areas, I think they missed the mark in others.