Hello dmainou:
Haldane
Haldane writes in his paper The Prevention of Compressed-Air Illness [J. Hyg. Camb. 1908, 342-443] Now the weight of blood in man is about 4.9% of the body weight
, and then he proceeds to show how by using the blood volume, the weight of a man, and the circulation time of blood, one can estimate the nitrogen content of the tissues as a function of time.
He states, On following out this calculation, it will be found that half the total excess of nitrogen would have entered the body after 23 rounds of the circulation, three-fourths after 46 rounds, seven-eighths after 69 rounds, and so on. The progress of saturation of the body with nitrogen is thus a logarithmic curve
The log curve is another representation of halftime. Time constants are not "statistical."
Surprisingly, half times, by that name, do not enter his paper and are mentioned nowhere in his paper. He does use the term half-saturation and is as close as you can come. The half-life term was just beginning to enter the world of physics with respect to the decay of radioactive elements.
Halftime
Half time comes from studies of the uptake and elimination of biomolecules and drugs in the body. Experimentally, it is very commonly observed process. There is a discussion of which diffusion process should be used for calculations in the body but no disagreement with respect to halftimes.
Dr Deco :doctor: