Bath curse tablets the Romans as "Aquae Sulis") were excavated between 1978 and 1983 by a team led by Barry Cunliffe and Peter Davenport. In 1979/1980, around 130 tablets were discovered in an excavation of the "Sacred Spring" under the King's Bath. The spring had been temporarily diverted to facilitate the excavation, revealing a huge array of Roman era items including the tablets. The tablets, some in a fragmentary state, were small and rectangular and initially were assumed to be made of lead, although subsequent metallurgical analysis revealed that they are, in fact, made of lead alloyed with tin, with occasional traces of
Aphanizomenon flos-aquae (dietary supplement) from the air, and water to synthesize proteins, carbohydrates, and lipids. AFA is also able to directly use molecular nitrogen from the air to produce proteins and other nitrogen-containing biomolecules. This ability is widespread in prokaryotes, but unknown in eukaryotes. "Aphanizomenon flos-aquae" as a species has both toxic and non-toxic forms. While benefits have been indicated, toxicity has been shown in some strains of the species "Aphanizomenon flos-aquae", with cylindrospermopsin and saxitoxins present, and microcystins found contaminating AFA dietary supplements. The World Health Organization's "Guidelines For Drinking Water Quality" note Anatoxin-a, saxitoxins, and cylindrospermopsins are present in the Aphanizomenon genus.