Lecture on Analytical Chemistry in BAC testing Part 8

The above is Part Eight from a lecture given by Attorney Justin J. McShane before the North Carolina Advocates for Justice “Advanced DWI Seminar”. This seminar happened on February 26, 2010. It was organized and hosted by John K. Fanney, Esquire of Fanney & Jackson, P.C. The following is a transcript of this video:

The reason that is important is for understanding the process of indirect measure. Remember I was talking about my daughter. You can put her on a scale and find out how much she weighs, or I can hop on the scale first and find out how much I weigh, and then put her on piggy-back style and find out how much we weigh together, and deduct my weight from the total to determine her weight. This is indirect measure.

That is what is happening here with hospital blood testing. With hospital blood testing we have this molecule which is ethanol and we add a reagent or an enzymatic process from NAD and it turns into NADH+ and it transforms from the original ethanol into acetaldehyde through alcohol dehydrogenase. That is the chemistry of it.

I don’t really expect anyone here to understand the chemistry but I am going to show you why this important. If you have lactate and apply this same principle of taking NAD + and converting it to NAD+H lactate dehydrogenase it results in pyruvate. The problem with the way the hospital blood is set up is that it is only looking at one particular wavelength and it is only measuring this portion, which is identical to lactate. This machine cannot tell whether the reaction is due to ethanol, meaning something your guy took, drank or lactate.  It is blind to that difference. If you are in an accident, if it’s using TCA it cannot tell the difference when this reaction occurs and when that reaction occurs. That is why you have watch for lactate.

Again, this is the entire spectrum.  We are only looking at the 340 range. To be very specific on how it is done and how it works, this is the absorbance, this is the wave length and we are only focusing on the zoomed in artifact instead of the whole thing.

The way it works is, instead of measuring the reaction deference to an enzyme at a specific wave length, hospital analysis is by enzymatic acid. As we talked about before, this is what happens normally.  This is what we would expect the spectrum to look like if there is no ethanol in it. When you add the NAD+ and do the process, you have this red line that is identical until it gets to about the 320 range but remember we are looking at the 340 range. By adding that process it makes the difference in the outcome of the wave length. It is like putting myself on the scale with my daughter on the back of me. It is designed to measure the difference as opposed to the uniqueness of alcohol. There are studies out there, it isn’t just ‘McShane says so’. You can read it. This is a graph that is important that highlights the danger of it.

We are looking at the 340 wavelength. What they did in this particular case study is use a subject with no alcohol, add trauma, TCA, lactated ringers and at the end you will get this over inflation. The problem is that there are no studies out there that show the contributory error. There is no way to subtract it from the process when lactated ringers are involved. The science does not exist. The most important thing is it is junk, it just doesn’t work.

There is a wonderful article that you can Google by our good friend Joseph Citron titled DUI/DWI: Hospital Laboratory Testing Lacks Forensic Reliability.

The end results, you get quotes like this, ‘most hospitals use a variation of enzymatic acid testing known as enzyme immunoassay or EIA’s of serum. This technique lacks the specificity to measure only ethanol. EIA is the most common chemical process in hospital laboratories’.

It is not specific and unfortunately, there is no way to meaningfully convert from a plasma blood result to a whole blood result in order for someone to come into court and say as an expression of his whole blood he was a .058 based on hospital blood method.

There is no agreement among the academics. It is overstated. They all agree that if you do a plasma or serum test it always overstates how much alcohol is in the system but they do not agree on how much. The problem is that the conversion factor is anywhere from as low as 1.18 overstatement, or 18%, to as high as 1.59, or 59% as I shared before. If you have that large of a swing, that is not generally accepted in the scientific community. I would not fly on a plane that says, ‘we are about 41% right that we are going to be heading in the right direction’. The bottom line is, it is absolutely guesswork. There are no conversion factors that exist that anyone can agree to.

We talk about the analysis of marijuana and specifically cystolithic hairs. These are different non-forensic methods of testing; the botanical ones we talked about before. I want to expose you to thin layer chromatography and exactly what it is.

Thin layer chromatography is very easy to understand. If you have ever seen a bounty commercial where someone spills something and it is the ‘quicker-picker-upper’; someone spills some coffee, ‘don’t worry about it, I have the world’s greatest paper towel and they quickly pick it up. Have you ever seen the commercial where they say, ‘ours is so great we can lay it on its edge and it is so absorbent that it sucks everything up’?  That is, in essence, thin layer chromatography although they do not explain it that way. It is based on what is called capillary action which is the drawing up from the bottom. It is very common in different drug abuse testing and it is just bad. There is no other way of putting it. It is not specific.  It is not quantitative.  It doesn’t tell you how much of anything.  It only tells you, much like this, that it may be present.

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