I mentioned in my previous post that the single greatest flaw in so-called "breathalyzers" is that they are designed to assume that all humans are physiologically identical. This is, of course, a false assumption, and I have mentioned examples in other posts of erroneous breath analysis attributable to human variability.
In the coming days, I will take a look at some further examples. Let’s take a look at one…..
Scientific research appears to indicate that in some cases a high blood alcohol level may not be indicative of alcohol consumption, but rather may be caused by a deficiency of zinc. In a study conducted at the University of North Dakota and reported in 46 American Journal of Clinical Nutrition 688 (1987), researchers experimented with the physiological effects of diets that had varied amounts of zinc.
They discovered that the metabolism of alcohol was dramatically affected by zinc intake. For example, they found that for those subjects on a low zinc diet, blood alcohol concentrations (BACs) increased rapidly within 15 minutes of consumption of measured amounts of alcohol: roughly twice as much alcohol was present in their blood at this time as was present in those subjects on normal zinc diets. Furthermore, greater amounts of alcohol remained in the blood for a longer period of time when there was a zinc deficiency — that is, elimination rates were decreased.
Thus, it appears that an individual with an insufficient amount of zinc in his diet will have higher peak BAC levels, and the alcohol will remain in his blood for a longer period of time. Among other things, this would render invalid any attempts at retrograde extrapolation — that is, estimating earlier BAC levels when driving based upon presumed rates of absorption and elimination. The human body is highly variable and, for that reason alone, police breathalyzers will never be able to provide reliable blood alcohol analysis.