Roman winemakers found that boiling of unfermented grape juice created a sweeter liquid known as defrutum or sapa. Defrutum is created by boiling off half the volume of wine, while sapa is the result of a reduction to one-third the original volume of wine. … The boiling process involved long hours and high temperatures, causing lead to seep out of the container, inadvertently artificially sweetening the sapa. … A modern attempt to re-create the sapa using lead vessels resulted in a liquid with a lead content of 2,900 parts per billion — one thousand times the acceptable dose in most countries.