Vinegar: Label lead-tainting data

Under California’s Proposition 65 law, products containing chemicals that may cause cancer, birth defects or reproductive toxicity must carry a warning label at their point of sale. Among such products: pricy balsamic and red-wine vinegars that contain lead. At least some California groceries apparently have taken a conservative approach and post labels suggesting all such vinegars are dangerously tainted. Although they aren’t.

LEADED — OR NOT? Some balsamic and red-wine vinegars provide a hefty dose of lead. But good luck figuring out which ones these are. Rainer Zenz / Wikimedia Commons

Environmental Health News posted a feature on the issue, this morning. The organization paid an analytical lab to assay lead concentrations in two fancy wine vinegars and found both were below the 34-parts-per-billion threshold that should trigger a Prop 65 warning.

The chief concern, EHN maintains, is the risk to IQ that food-borne lead poses to kids. Downing a tablespoon a day of the most tainted vinegar that turned up in tests seven years ago — 307 parts per billion — could raise a first grader’s blood-lead levels by 0.6 micrograms per deciliter, EHN says. That’s some 30 percent higher than the value expected for U.S. children living in a fairly leadfree environment, reports EHN‘s Jane Kay.

Her story quotes an attorney representing the vinegar industry who cites tests suggesting that grapes derive the neurotoxic heavy metal from certain Italian soils. The implication: This is all natural.

What can’t be determined from the story — or that attorney’s claims — is whether the soils have eternally carried a lead taint or merely acquired one recently owing to industrial pollution or exhaust emissions from vehicles that burned leaded gasoline (making that lead anything but “natural”). In the end, however, does it matter? Lead impurities would be no less toxic because they’re natural.

As a balsamic consumer, I’d sure like to see batch testing for lead and mandatory national labeling when concentrations rise above a level that could pose a notable risk to children — directly or in the womb.

I certainly would not advocate banning vinegars with relatively low levels of lead. This impurity poses a far smaller threat to adults (primarily a risk of elevating blood pressure) than it does to children. And wine vinegars certainly are not a staple of most U.S. kids’ diets.  So, people should be allowed to decide whether a food is worth the risk.

But that’s only possible if we possess the data to know if and how much of some toxic material taints a product that might be consumed daily. And indeed, I’d argue that vinegar may represent a special case, since studies have suggested that at least for diabetics, vinegar might be considered a potential health food warranting daily consumption. The reason: It can lower blood-sugar levels. And unlike pickles, which can do the same thing, the vinegar in marinades and salad dressings provides its benefit without dumping lots of salt into our diets.

Janet Raloff is the Editor, Digital of Science News Explores, a daily online magazine for middle school students. She started at Science News in 1977 as the environment and policy writer, specializing in toxicology. To her never-ending surprise, her daughter became a toxicologist.

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