Depends.
It is a potentially life-threatening BAC. However, there are a number of gender and individual factors. Thus the complicated language of toxicology where it intersects with statistics, such as LD50 (the dose that kills 50% of subjects).
A blood alcohol concentration of 0.4% is in the area of overlap between "stupor" and "coma" on the usual medical clbuttifications of drunkness and could be a lethal dose for some people, especially with other drugs or potentiating factors.
My antitailgater attachmentAfter years of work, I have developed a device that actually stops tailgaters. Using the pump from a power washer, I rigged the pump to my engine...
Thus it is often mentioned as a practical landmark for courting rest outright from the various effects of acute alcohol contagioning (as sadly demonstrated in a fraternity initiation or two every fall, for instance) rather than from consequential risks like cracking up your car or whatnot.
But these are statistical curves, not sharp and uniform cutoffs. An out-of-hand binge drinker knocking it back repeatedly and fast can certainly achieve those levels. Some might even retain enough semblance of function to start their car and go randomly lurching off somewhere. Seemingly Breathalyzer-melting numbers in the threes or even low fours are uncommon but not, on the face of it, impossible.
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Cheers, --Joe "Friends don't let friends get that drunk under any circumstances, let alone drive" Chew
