Lead in wine.

Elevated levels of lead in wine have been explained by several possible contamination sources: leaded gasoline, tin-lead capsules (used to cover the bottle neck), and brass alloys. Lead measurements from 7000 wines were used to identify possible sources and these showed that atmospheric pollution-related contamination (leaded gasoline) was not responsible for elevated lead concentrations in wine. It also was shown that the presence or absence of tin-lead capsules as well as the state of tin-lead capsule corrosion had only a very minor influence on the lead concentration in wine. The reported positive correlation between wine age and lead concentration was confirmed by our data. However, further statistical analysis revealed that not the age of wine but the vintage and the wine colour were the most significant contributing factors. The wine age itself was no longer correlated with the lead concentration after controlling for the significant variables mentioned. The conclusions drawn agree well with the explanation that brass is the main contamination source. Inspections of wineries known for elevated lead levels always revealed the presence of brass tubes and faucets. There has been a continuing and significant reduction of lead levels in wine during the recent 7 years where measurements were made.