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 toxic chemicals released when cells die. Once released (lysed), and ingested, these toxins can damage liver and nerve tissues in mammals. In areas where water quality is not closely monitored, the World Health Organization has assessed toxic algae as a health risk, citing the production of anatoxin-a, saxitoxins, and cylindrospermopsin. Dogs have been reported to have become ill or have fatal reactions after swimming in rivers and lakes containing toxic "A. flos-aquae". Microcystin toxin has been found in all 16 samples of "A. flos-aquae" products sold as food supplements in Germany and Switzerland, originating from Lake Klamath: 10 of 16