In article ,
John Williamson wrote:
(Definition 2) CO2 is harmful or deadly to most animal life when
concentration in the breathing gas is excessive. Therefore, it is toxic.
Admittedly, not as toxic as a lot of other gases, including carbon
monoxide, but still toxic.

Oxygen is deadly to most animal life when in concentration too.

There's a difference between something not supporting life and being toxic
- even although the end result may be the same.

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*We have enough youth, how about a fountain of Smart?

Dave Plowman London SW
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