Grey, soft heavy metal or element (Pb = plumbum) that occurs in nature mostly as galena. It is present in all plants and also in wine in minute quantities, but has no biological function and is dangerous as a neurotoxin. Lead can cause developmental neurotoxicity (harmful changes in the structure or function of the nervous system) in young children and cardiovascular problems (diseases of the heart, blood vessels and non-specific weakening of the cardiovascular system) and nephrotoxicity (kidney damage) in adults.
In ancient Rome, lead was used to sweeten and preserve wine and was fatally recommended by Pliny the Elder (23-79). In the Roman Empire, preparing food and boiling wine in lead vessels was common; for example, the grape syrup Defrutum was made this way. That the Romans slowly poisoned themselves and that lead was ultimately the reason for the fall of the Roman Empire is, however, only an unproven hypothesis. The picture shows a lead-glazed ceramic bottle from Syria in the shape of a grape from the 1st century AD.
Adding lead acetate or lead oxide (lead sugar) to wine was common throughout Europe until the 19th century because it tastes sweet and is easily soluble in water. It was not until late that the dangers were recognised. Depending on the wine laws in force, however, this was already considered wine adulteration in some countries and was severely punished. It took until the beginning of the 20th century, however, until the use of the toxic metal was prohibited by corresponding laws in all countries.
In the meantime, the use of lead-containing insecticides is prohibited in viticulture and the use of lead-containing foils or capsules is also banned. It accumulates in the soil (like all heavy metals) and is very difficult to break down. Most of the traces contained in the grapes (for example through exhaust fumes from motor vehicles in the case of vineyards located near roads) are broken down during fermentation and fining and then excreted with the lees. According to EU Regulation 2021/1317, the maximum content for "wine from grapes" was set from 0.2 mg/kg to 0.1 mg/kg in August 2021. The maximum content for fortified wine and liqueur wine made from grapes is now 0.15 mg/kg. This will apply from the 2022 vintage onwards, and most wines will be well below this limit. See a list of all toxic substances in wine (with their limits) under ADI (acceptable daily intake).
Vessel: by AgTigress - Own work, CC BY-SA 3.0, link
Lead lump: by Rob Lavinsky, iRocks.com - – CC BY-SA 3.0, link
