G. Giachi et al., PNAS Early Edition (2013)

Canned relief. A Roman-era medicinal compound (right) was found in this tin "pyxis."

Ancient Eye Treatment Recovered From Tuscan Shipwreck

Medicinal tablets retrieved from a 2000-year-old shipwreck suggest that classical Mediterranean civilizations had sophisticated drugs.

Around 130 B.C.E., a merchant ship sank just off the coast of Italy's Tuscany region. The wreck was spotted in 1974 and dubbed the Relitto del Pozzino after the beach near where it was found. Archaeological excavations in 1989 and 1990 yielded glass bowls, amphoras for carrying wine, lamps, and tin and bronze vessels all likely to have come from the eastern Mediterranean.

There were also artifacts presumably contained in a wooden chest that had rotted away: wooden vials, a cup possibly used for blood-letting, and other objects likely to have been found in an ancient physician's medical bag. Among them was a small tin cylinder known at the time as a "pyxis," that contained five tablets that were about 4 cm in diameter and had been preserved from the elements by a tight-fitting lid. Italian scientists recently analyzed fragments from one tablet and found primarily two zinc-rich materials (hydrozincite and smithsonite), as well as various animal and plant residues, pollen grains, beeswax, and pine resin. In a paper appearing online today in the Proceedings of the National Academy of Sciences, the scientists argue that the writings of Pliny the Elder, a Roman, and Pedanius Dioscorides, a Greek, both recognized by classicists for their writings on medicinal materials, claim these zinc compounds were once thought beneficial for the eyes and the skin. And they note that the Latin word for eyewash, collyrium, derives from a Greek word meaning "small round loaves."

"This is a fascinating paper on a very interesting set of new finds," says Richard Evershed, a chemist at University of Bristol in the United Kingdom. He adds that the chemical and microscopic analyses "seem robust, although there are aspects I would have pursued in further detail." He is less sure that the materials were really used to treat the eyes, though he agrees the case is strengthened by the links to the classical literature.

The tablets were originally thought to be vitamin pills sailors might take while on long voyages. But the researchers have concluded that "the tablets were directly applied on the top of the eyes," says Erika Ribechini, a chemist at the University of Pisa and a co-author of the report.

Despite lingering questions about the use of the tablets, the study "provides a further example of the high level of knowledge our ancestors possessed concerning the properties of natural materials and technologies required to refine and manipulate them to provide improved products," Evershed says.

Posted in Chemistry, Health, Archaeology