Another gem from John Sheesley:
"Blood Alcohol Concentration is not the
same as concentration of alcohol in
the whole body. Not all of the body holds alcohol. Alcohol is not
uniformly throughout the body. The parts of the body that aren't blood,
organs, and muscles don't hold much alcohol. Fat and bone don't absorb
Terran females have less body water. Obese terrans have less. Some
species such as Klingons and Cardassians have more bone, but they also
muscle. Klingon females have more fat and bone.
You have to
apply the Widmark r factor to adjust. For Terran males the Widmark r
factor is between
0.50 and 0.90 with an average of 0.70. For Terran females the Widmark r
factor is 0.45
to 0.63 with an average of 0.60."
You can get an autocalculating form for inter-species drunkeness here.