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I purchased several small bottles of balsamic vinegar for party favors for friends. Once home, I noticed that the warning on the side says that this product contains lead!
Why would balsamic vinegar contain lead? Or is the glass bottle it's in? I'm concerned about ingesting this type of chemical. Are all balsamic vinegars made that way?
I checked with an importer and it appears that there are trace amounts of lead in some vinegars. The key word is trace amounts. The controversy grows out of a group known as the Environmental Law Foundation who sued a number of manufacturers and sellers of balsamic vinegars because their products contained lead. In California, under a law passed in 1986, no food products may be sold that contain certain toxins without a warning.
The law in California has a safety margin of 1,000 fold. This means that foods have to be labeled as containing lead if they have more than 1,000 times lower than the level that causes an effect in humans. California is the only state that requires this warning on labels.
It appears that there is some controversy about where the lead comes from that is found in vinegars (some red wine vinegars appear to have lead as well). Some say that is from lead that is naturally absorbed into the grapes from the soil. There is some feeling that the lead might happen during the manufacturing process. Neither of these theories have been proven. It does not appear that it has to do with the glass bottles.
It appears that the amount is very small and we generally use only small amounts of vinegar -- a tablespoon per serving or so. This is from the web site of one seller, Napa Valley Trading Company:
Most balsamic and red wine vinegars have lead levels equal to or less than 34 parts per million. An average person would need to consume 1 to 2 cups of balsamic or red wine vinegar per day to reach the Proposition 65 lead level minimum threshold, which includes a 1000-fold safety margin.
I use balsamic vinegar in recipes, and in such small amounts that I am not personally concerned.
Thanks for writing,
Timothy S. Harlan, M.D.