if you're going to try to boil water in a plastic bottle over a fire, should you fill it all the way to the brim or leave a little room at the top?

I noticed that Bear grylls did the same thing in one of his episodes ... he boiled water in a plastic bottle over a campfire. It is an intriguing idea, but I wouldn't do it if i needed to drink hot water or make some tea. The risk of chemical contamination is too high. It might be OK if the hot water is for external use, or cleaning purposes.

other Pete

Every fruit, nut, and vegetable in existence contains "poisonous" chemicals. Assuming you have a functioning liver, the amount and type of chemicals you'd ingest from occasionally heating water in a plastic bottle won't harm you.

-Blast

I enjoy watching it regardless of it's survival value (not nil either, some tricks are quite fresh to me). Very nice couple in the center of quite thrilling adventure.

Hey Blast ... you sure about that??
Take a look at the Bear Grylls episode, or try it yourself at home. In order to boil the water in a plastic bottle, you really wind up frying the bottle over the flames. The plastic comes out blackened, shriveled up, and very nasty. It doesn't look good at all.

Food for thought!
other Pete

That was only last year that the lady tried the BPA scare on us. Wonder how many forums she tossed that garbage out.

Sounds like it's time to experiment, but it'll have to wait until next weekend. I'll report back the results.

-Blast

Chemical myths about plastic from John Hopkins University. Sidenote: when he get's to the part about phthalates (PBA) he neglects to mention how little phthalate gets extracted by hot water. I'm too tired to look up my calculations based on the most commonly quoted research papers on this subject but it was in the thousands of LITERS of water per KILOGRAM of body weight before you had enough to POSSIBLY have some noticeable effect on the body. I suspect that much water would cause a problem before the phthaltes would.

-Blast

Just watched the episode in Alaska. They have failed to survive there because of a complete lack of food. My question is about the snow cave they've dug for sleeping. It was a mistake to keep the large entrance wide open, is not it? As far as I can recall you have to seal it as best as you can leaving just a very small opening at the bottom for ventilation. They were also suffering from a headache in the morning, most likely because of the smoke from the fire in front of the entrance entering the cave all night long.

I'm picking more and more useful tips from the show. The problem is that many of them comes without a proper explanation, sometimes with only several seconds of partially obscured demonstration. It looks like the makers tend to concentrate on the drama aspect too much - still fun overall though.

Alex you touched on something I failed to mention in my first response here on the show. Myke does actually try to explain what he is doing and how to do it, whereas Les & Bear just do.

When his wife got dehydrated in the desert and he started a fire, he was honest enough to show and tell it took 90 minutes to do with the technique he was using. I am occasionally asked to start fires with what is on me or what is available (BBQ joking around) and people get bored after five minutes watching me strike or rub objects.