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eerily 12
Jun 11, 2012, 08:21 AM
He drank one beer eight hours before a UA bac/etoh test. Then he tested using his fist void urine. What are the likely results?

DrBill100
Jun 11, 2012, 08:33 AM
By first void do you mean that he hadn't urinated since the beer or first void of the day?

The elimination time for one beer would be 2 hours (at most) but urinary content will remain there until the bladder is emptied.

Second factor, EtOH tests usually do not measure below the .02 range (+/- 20%). That renders detection of a single drink by this method unlikely even within a couple of hours.

eerily 12
Jun 11, 2012, 08:41 AM
By first void do you mean that he hadn't urinated since the beer or first void of the day?

The elimination time for one beer would be 2 hours (at

most) but urinary content will remain there until the bladder is belief the .02 range (+/- 20%). That renders detection of a single drink unlikely even within a couple of hours.

He believes he urinated directly after drinking the beer, but doesn't remember for sure then first void of the day, eight hours later.

DrBill100
Jun 11, 2012, 08:46 AM
That would indicate that the EtOH was still present in urine but it is still unlikely to be detected due to the metabolic pathway for small amount of alcohol. It is unlikely that his BAC ever went beyond .015. How much does he weigh?

eerily 12
Jun 11, 2012, 08:54 AM
179 lbs, he ate a full meal with his beer

DrBill100
Jun 11, 2012, 09:07 AM
179 lbs, he ate a full meal with his beer

It is likely that his BAC never exceeded .01 at peak given size and meal. Very unlikely that EtOH can be detected. The reason is that in the presence of food the alcohol is retained in the stomach, metabolized by ADH and never makes it to the blood stream.

This type of test is not calibrated for precise readings.

eerily 12
Jun 11, 2012, 09:49 AM
It is likely that his BAC never exceeded .01 at peak given size and meal. Very unlikely that EtOH can be detected. The reason is that in the presence of food the alcohol is retained in the stomach, metabolized by ADH and never makes it to the blood stream.

This type of test is not calibrated for precise readings.

Thank you for your frankness. The final part of the question then is, "will any alcohol be detected in the urine sample?"

DrBill100
Jun 11, 2012, 10:00 AM
Given the 2-step process of EtOH testing and the inherent limitations of Step 1 I can't see how alcohol could be detected.

Step 1 is conducted by an immunoassay that has a fixed cutoff, could be .02 or as high as .04. If this step returns a negative then the more precise confirmatory test (Step 2, that can detect lower amounts) is never implemented.

Once again, Urine EtOH testing is not of a design to detect low level consumption.

eerily 12
Jun 11, 2012, 11:15 AM
Given the 2-step process of EtOH testing and the inherent limitations of Step 1 I can't see how alcohol could be detected.

Step 1 is conducted by an immunoassay that has a fixed cutoff, could be .02 or as high as .04. If this step returns a negative then the more precise confirmatory test (Step 2, that can detect lower amounts) is never implemented.

Once again, Urine EtOH testing is not of a design to detect low level consumption.

Thank you, Dr. Bill. :)