Dry Ice Drop

[Ike]

I was quite sure that, unlike nitrogen that only poses a danger by displacing oxygen, carbon dioxide actually does you harm.

[TomLyall]

any biologists/chemists here? carbon monoxide is actually toxic as it binds with heamaglobin to form a stable compound carboxyheamaglobinm, although I always thought carbon dioxide either didnt react with heamglobin, or was not stable.

 

someone correct me or shed some light, please! :unsure:

[kalmatthew]

A quick Google makes it look like Carbon Dioxide in only harmefull as an asphixant (sp?). Although I could be wrong.

[tonythetechie]

Carbon dioxide eradicates the oxygen from the air therefore in large quantities can be quite potent.

 

As Kal says it's an asphyxiant, literally it'll suffocate you if it covers you. :unsure:

[Tomo]

I was quite sure that, unlike nitrogen that only poses a danger by displacing oxygen, carbon dioxide actually does you harm.

The main differences between CO2 and N2 exposure are that CO2 is heavier than air and so will tend to 'pool' in low areas before dispersing (so may require evacuation fans), and that the safe concentration for N2 is about 90%, while the limit for CO2 is well under 5%*

 

Concentrations in normal air are around 78% N2, 21% O2 and approx. 0.1% CO2, with things like Argon, water vapour and other stuff making up the rest.

 

CO2 doesn't associate with haemoglobin much, but is carried dissolved in the blood - so excess CO2 makes your blood acidic, but you asphixiate before that becomes significant in the short term.

 

There's no long-term effects currently known caused by occasional mild CO2 poisoning, although continous non-lethal exposure is probably bad.

 

(*Last guesstimate I heard was around 3% CO2 for continued exposure, but that is associated with headaches)

[peter]

Following on from this, does anyone know of a good UK supplier for Dry Ice? I've had a quote from BOC, but I'm sure there must be someone else who can supply it. I've tried local hospitals and chemistry departments, but they all say they use BOC. The really crippling thing about BOC is the delivery charge, but obviously if the list price of an alternative supplier was less then that would be an option. We're after about 10 bags of pellets.

 

Peter

[robloxley]

CO2 can be toxic if you inject lots of it into the brain, used for cerebral angiography. 'Excess CO2' in your blood does cause acidosis but your body compensates for that by various mechanisms. However, the main issue is displacement of oxygen by CO2 or indeed N2.

[V*L Ben]

usually its no the CO2 dats the problem, it getting rid of it. Another point, Dry ice Doesn't inhabit life, so as long as ur head isn't @ ground level, you should be ok in an open(ish) area. (Chemistry teachers r useful 4 dis kinda stuff) :)

[Ike]

I don't think many forms of life could survive in dry ice (as in solid carbon dioxide) however the smoke effect it produces (as in water) will at worst give you a sore throat.

There is of course the problem of the CO2 gass also produced.