Why Terra Sigillata?

[This post appeared originally at my Blogspot site on 20 December 2005 to describe my rationale for the name of this blog. With today's traffic from the Daily Kos, I thought it would be useful to new readers to know our story here. FYFI, here is why I chose the pseudonym Abel Pharmboy. - APB]

If you Google, "Terra Sigillata," you'll get a number of hits for various clay pottery recipes. Very complicated stuff, requiring the use of a deflocculant to separate out large clay particles from the small ones. Terra sig, as it is known among pottery hipsters, is then used to coat finished pieces to produce a very smooth, high luster and waterproof finish.

What does this have to do with pharmacology and natural products?

Terra Sigillata literally means "sealed earth." In the common potter's vernacular, "seal" probably relates to the waterproof character of the product. But, in ancient pharmacy history, Terra Sigillata refers to the first trademarked drug product, a small clay tablet or planchet bearing an official mark of authenticity. In this case, the "seal" was a mark for trade and marketing purposes.

Yes, pre-Christian cultures ingested dirt (but only special dirt) as medicine. (Admonishment from my soil scientist colleagues: I meant to say, "soil" - sorry.). Terra Sigillata was a rather fatty clay first harvested around 500 B.C. from a particular hill on the Mediterranean island of Lemnos, now part of Greece. Dug on a special day annually in the presence of governmental and religious dignitaries, the clay was rolled to a defined thickness and pressed with an official seal by priestesses and dried in the sun. Kind of reminds me of my favorite beer, Samichlaus, brewed once a year on 6 Dec.

Known as geophagy today, the practice is not as odd as it sounds. Today, we now know that clays contain kaolin (an active antidiarrheal component of Kaopectate), minerals like iron oxides and others like calcium carbonate and magnesium hydroxide that may have served as nutrients or antiacids. Moreover, various ethnomedical cultures have encouraged clay consumption by pregnant women, both to ease nausea and to adsorb dietary alkaloids and steroids present in the plant diet from harming the developing fetus.

People learned early of the prestigious advantage of trademarks as a means of identification of source and of gaining customers' confidence. One of the first therapeutic agents to bear such a mark was Terra Sigillata (Sealed Earth), a clay tablet originating on the Mediterranean island of Lemnos before 500 B.C. One day each year clay was dug from a pit on a Lemnian hillside in the presence of governmental and religious dignitaries. Washed, refined, and rolled to a mass of proper thickness, the clay was formed into pastilles and impressed with an official seal by priestesses, then sun-dried. The tablets were then widely distributed commercially. From a modern point of view, the ingredients (silica, aluminum, chalk, magnesia, and traces of oxide of iron), indicate that this clay might be expected to act as an adsorbent.

In the early days, and even up to the early nineteenth century, Terra Sigillata was used as an antidote for poisons as well as in the treatment of dysenteries, int ernal ulcers, hemorrhages, gonorrhea, pestilential fevers, complaints of the kidneys, and eye infections. The most striking feature of this drug, however, was the way in which it was marketed, and the method of identifying it and warranting its origin from a definite source. The great demand for Terra Sigillata and the good business that the sale of these troches brought caused people in almost every country in Europe to look for similar earths. This trademarking to protect the rights of seller and buyer today has behind it the sanction and approval of some 2,500 years of man's experience in world commerce.

Having lived in the southern US for over a quarter of my life, I'm also aware the red clay of the southeastern region is highly regarded for settling the stomach. According to John and Dale Reed in "1001 Things Everyone Should Know About the South," the practice of geophagy seems to have originated in Africa and was widespread in the 19th century South among the poor of both races. The Reeds claim that the taking of the clay is the source of "sandlappers," a nickname for South Carolinians. Heck, I've even heard Michael Stipe of R.E.M. (and Athens, GA) remark that red clay is in his blood, although I suspect his claim may be more figurative.

I learned of all this great history when I began leafing through a classic 1965 pharmacy history book, "Great Moments in Pharmacy History." (Washington State University's College of Pharmacy received permission to post the images online; here is the painting and brief description of Terra Sigillata.) The drug company then known as Parke, Davis & Company, commissioned Robert A Thom, a Birmingham, Michigan artist, to prepare paintings of historical scenes to accompany historical text collected by Prof George A Bender from pharmacy sources worldwide.

It's a great book that can be found through e-tailers focusing on out-of-print texts. If you went to pharmacy school anytime since the mid-1960s, you know what I'm talking about because Thom's unmistakable portraits can be found in labs and offices in most US colleges of pharmacy.

The idea of Terra Sigillata stuck with me. When thinking of a name for this blog, I didn't want to restrict it to plants or fungi or soil microorganisms because creatures big and small, terrestrial and oceanic, have been used as sources for medicinal agents. I had certainly known that my predecessors had been culturing soil for novel medicinal-producing organisms since Selman Waksman first discovered streptomycin. But I frankly hadn't realized that the Earth itself had been used as a medicine.

Hence, Terra Sigillata is a metaphor for the fact that the Earth itself has provided medicines to various cultures for centuries.

The trademarking aspect of Terra Sigillata also holds significance for thinking about how important drug branding has become in our current culture, both for the buyer and the seller. Whether declared by a priestess, a charlatan, a shaman, a late-night infomercialist, or a drug regulatory agency, branding carries with it some implicit guarantee of quality or assurance of purity of authenticity.

Or not.