classic science papers – The Big Room (and the little things in it)

The rightful place of science, and “The definition of an intoxicating beverage”

Just a brief point first: President Obama in his inaugural address promised to “restore science to its rightful place.” In traditional fashion, this prompted all manner of verbosity on blogs around the web concerning just what science’s rightful place actually is. Let me just take a moment to settle this question:

Science’s rightful place is kneeling at my feet in supplication and doing my bidding! AH, HA HA HA HA HA!!!!!

But that’s not what I came here to post about. Instead, I wanted to mention a paper I finally got my hands on. You may recall that some time back there were a few stories that popped up about what was said to be a “you can’t get drunk on beer” paper published back in the 1950’s. As usual, the people doing the reporting couldn’t be bothered to actually cite the paper in question, but I figured out which one it was. The paper is this one:
Greenberg LA:”The Definition of an Intoxicating Beverage”; Q J Stud Alcohol. 1955 Jun;16(2):316-25.

I have that paper. And I am quite disappointed in it in much the same way I was with Linus Pauling’s paper proposing a triple-helix structure for DNA. I did, though, learn some interesting things from Greenberg’s paper.

It turns out that the paper actually concerns the legal definition of “intoxication” and whether or not, based on this definition, beer should be classified as an “intoxicating beverage”. Greenberg actually raises some good points…but first, some amusement:

“The average alcohol content of American beers is 3.7 per cent[…]The strongest ale is 4.2 per cent” (page 320, paragraph 4)

Unfortunately, this isn’t quite as funny as it sounds, because the part I clipped out of that quote is where he says “by weight”. It’s still kinda funny though, since that would mean, in mass-market-bladderwash terms, that “The Strongest Ale” is Heineken.

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This Alcohol-by-Weight-vs-Volume issue may actually be part of why American beers have a reputation for having watery, feeble beers. It evidently used to be that places like Canada were using alcohol-by-volume, while the US was using alcohol-by-weight on their labels. An otherwise-identical beer bottled in Canada would have a higher “percent alcohol” on the label than the US-bottled version, making it seem as though the American version was weaker. So, evidently it’s not really true…things like “Coors Lite” notwithstanding. (See this recent page at Fermentarium.com for more details.)
—

But back to the point of the paper…evidently as Greenberg was writing this paper half a century ago, there wasn’t a clear, quantitative scientific or legal definition for “intoxication”. He points out that you can’t just define it in terms of alcohol merely having noticeable effects on the drinker, since the magnitude of the unpleasant effects at low to moderate drinking levels aren’t really much different than that for (for undesirable effects) lack of sleep, distraction [remember all those studies saying talking on the cell-phone while driving is as bad as being drunk?], hunger and so forth. For that matter, I think we can all see the problem of trying to arrest anyone who is being relaxed and amiable for “public intoxication”.

Greenberg solves this problem by looking at the average blood-alcohol concentration of people arrested for “intoxication” (0.21% back in the 1950’s, evidently), and a couple of previous studies from the 1920’s and 1930’s, and he finally settles on 0.15% Blood Alcohol Concentration as a level he’ll use as the line for “definitely intoxicated”. He then proceeds to go through the common classes of alcohol-containing beverages to determine how easy it is for someone to consume enough to reach this BAC.

In summary – For hard liquor, and average person would have to consume 8 ounces plus one ounce per hour of drinking (for example, 9 ounces consumed over the course of one hour). That’s not a difficult quantity to fit into a typical stomach, so hard liquor is obviously an “intoxicating beverage”. Fortified wines (like Port, Madiera…or Thunderbird): about 18 ounces plus 2 ounces per hour – say, a pint and a half in about 4 hours. Still pretty easy to do. An ordinary wine (like, say, a Gewürtztraminer): 36 ounces plus 4 ounces/hour – or a 7-11 “Super Big Gulp®”-sized portion in two or three hours. Getting to be a fairly substantial amount of liquid, but still plausible.

And then there’s beer. Greenberg comes up with a figure of 80 ounces + 10 ounces/hour. That’s roughly three quarts within one hour, which is quite a bit more than the approximately 2 quarts that a human stomach can hold. He goes on to describe several controlled experiments on beer consumption and the resulting blood-alcohol concentration. By pushing one group to consume a gallon and a half of beer over a period of 8 hours, they were able to get up to an average of just under “intoxicated” (by Greenberg’s definition) at 0.13%. The rate of beer ingestion required to pass the “intoxication” threshhold was more than most test subjects could even manage. Therefore (Greenberg concludes) beer should probably not actually be classified as an “intoxicating beverage”

Now for the party-poopery: Greenberg explicitly points out that this is certainly not the same as saying that beer cannot impair a drinker’s performance or judgement, so just because you haven’t consumed anything stronger than beer it doesn’t mean you should be allowed behind the wheel of a steamroller. Nor does it mean that it’d be okay for an alcoholic to drink beer (since an alcoholic is very unlikely to stop with just beer). Furthermore, these days “intoxicated” is legally about half of the level that Greenberg is using – 0.08% in most places in the US as far as I can tell. By Greenberg’s measure, you can easily get that amount of alcohol out of a pitcher of beer consumed over an hour.

So, Greenberg isn’t crazy, and beer can still make you drunk, just as we all would expect. How disappointing. Still, it’s an interesting paper and I’m glad I dug it up.

On a related note, if I can get my hands on an old paper from the Journal of the Institute of Brewing, I may have found my selection for February’s Giant’s Shoulders blog carnival. Stay tuned, more to come…

“A Proposed Structure for the Nucleic Acids”

Hello again, girls and boys and whatever else may be out there reading. It’s time once again for this blog’s contribution to The Giant’s Shoulders (hosted this time over at “Second Order Approximation“). This month I’m looking at something even smaller than usual. Inspired by my new job in the biochemistry department where they seem to do a substantial amount of X-ray crystallography (which I do not – yet – understand as well as I’d like), I thought I’d drop all the way down to the molecular level and talk about a fundamental discovery that helped make modern molecular microbiology possible: the structure of DNA.

Yes, it was over a half-century ago that an accomplished scientist, working with X-ray images produced from crystallized nucleic acids, published the first proposed structure for for them – the famous Triple Helix.

Continue reading “A Proposed Structure for the Nucleic Acids”

“A simplified method of staining endospores”

One more for the “classic papers” challenge:

Schaeffer AB, Fulton MD: “A Simplified Method of Staining Endospores”; 1933; Science; 77; pg 194

If you take a microbiology lab, this is the endospore staining technique (or “technic” as they used to spell it) that you’ll practice. This is a nice, simple, one-page paper. Alice B. Schaeffer and co-author Mac Donald Fulton describe a few of the other variations on endospore staining techniques, then describe how they’ve further simplified what they felt was previously the simplest one, described by a Mr. Wirtz in 1908.

“Endospores” are a sort of “escape pod” for certain specific kinds of bacteria. Unlike spores formed by yeasts and molds, these are not reproductive – each bacterium only produces one thick-coated spore, into which it shoves it’s genetic material and a few vital enzymes to get itself going again later when the spore finds itself in favorable conditions.

Since only a few kinds of bacteria produce these endospores, if you see endospores in your unknown bacterial culture it goes a long way towards helping to identify the bacterial species, so having a simple method for staining your bacteria so that endospores are obvious under a microscope is helpful. (Of course, these days most of us would rather just get a 16s rDNA sequence with PCR, but never mind that for now…)

Evidently, Wirtz’s original method involved using Osmium Tetraoxide (“osmic acid”) to stick the bacteria to the slide before staining. Not only is that stuff poisonous, it’s also expensive. I found a site selling sealed glass ampoules containing 1 gram each of this stuff for $35.00 each. Schaeffer and Fulton’s method does away with this in favor of much cheaper and easier heat-fixing (just as is done with the Gram stain and others). They use the dye “Malachite Green” for the initial stain, and steam-heat the dye-covered bacterial slide a few times to sort of “cook” the dye into the thick-walled endospores if they are there. Rinsing then washes the dye out of everything but the endospores, and a light red dye (safranin) is added as a counterstain. The end result is that under the microscope you’ll see light-red bacteria. If any of them form endospores, you’ll be able to see them as smaller green dots – sometimes still bulging inside of bacterial cells, sometimes floating around freely having escaped from the now-empty bacterial cell.

The “Schaeffer-Fulton Endospore Stain” is pretty easy to do, though the occasionally messy steambath part can be annoying. The method is pretty resistant to errors, so it’s not too hard to get good results even if you’ve never done it before.

Incidentally, you can buy Malachite Green at many pet stores – it’s still used as a treatment for “ick” (Ichthyophthirius infestation) in tropical fish.

Hmmm…still a couple of hours before it’s not longer May – Perhaps I can throw in one last post before time’s up…