Bob Lee Swagger wrote:

"CO2 is actually toxic in high concentrations. I don't know about 2000 ppm
but it sounds dodgy to me. Higher than that could be scary. Let's not
shoot
for it, ay? "



Reply: Right now, we are at about 380 or 385 ppmv (parts per
million)

2000 ppmv is only TWO TENTHS of 1%. ( point 2)
(.2)

Well to get you a little dizzy in a crowded room you
would need 1% CO2 in the air. 10,000 ppmv
You might think it was the three drinks you had.

2% would increased blood pressure and pulse rate, and
causes reduced hearing. 20,000 ppmv
8% will cause headache, sweating, dim vision, tremor
and loss of consciousness after exposure for between five and ten
minutes. 80,000 ppmv

All this information is online here on the Internet, and in
textbooks.


More then that can of course kill you.
" However, Adaptation to increased levels of CO2 occurs in humans.
Continuous inhalation of CO2 can be tolerated at three percent
inspired concentrations for at least one month and four percent
inspired concentrations for over a week. It was suggested that 2.0
percent inspired concentrations could be used for closed air spaces
(e.g. a submarine) since the adaptation is physiological and
reversible. Decrement in performance or in normal physical activity
does not happen at this level."
From Lambertsen, C. J. (1971). "Carbon Dioxide Tolerance and
Toxicity". Environmental Biomedical Stress Data Center, Institute for
Environmental Medicine, University of Pennsylvania Medical Center
(Philadelphia, PA) IFEM Report No. 2-71. http://archive.rubicon-foundation.org/3861.
Retrieved on 2008-05-02.
^ Glatte Jr H. A., Motsay G. J., Welch B. E. (1967). "Carbon Dioxide
Tolerance Studies". Brooks AFB, TX School of Aerospace Medicine
Technical Report SAM-TR-67-77. http://archive.rubicon-foundation.org/6045.
Retrieved on 2008-05-02.

But you don't have to worry even at much higher then 2000 ppmv.
which is what it was 100 million years ago during the dinosaurs.

Because,,, 2000 ppmv is only TWO TENTHS of 1%.
( point 2) (.2)

You would need 10,000 ppm to even come to 1% CO2. That ain't ever
going to happen. And even if it did, like studies show, humans have
the ability to physiologically adapt to 1%.

The U.S. Occupational Safety and Health Administration says
that average exposure for healthy adults during an eight-hour work day
should not exceed 5,000 ppm (0.5%). That's more then twice what the
level was back in the time of the dinosaurs. So you don't have to
worry and lose any sleep.

In other words, even if CO2 in the atmosphere was at 2000 ppm, and
everything else was the same as now, you would notice nothing
different from what you notice now.
Therefore, you can relax.