Is there lead in your salad dressing?

(Photo: Getty Images)

If balsamic or red wine vinegar is a major ingredient, then chances are the answer is yes.

This is surprising news for most people, even those who live in California where signs in grocery stores warn about lead in some vinegars (thanks to Proposition 65 which requires that stores warn consumers about toxins in products).

No one is suggesting that you stop eating balsamic vinegar, but it's not a bad idea to use it in moderation. Lead is a potent neurotoxin that can damage children's developing brains and cause learning disabilities. It can cause high blood pressure, reproductive complications, and cancer in adults, according to the Environmental Defense Fund.

The amount of lead in most balsamic and red wine vinegars is small and varies depending on product, according to an article in Environmental Health News, however regularly consuming it might pose a risk especially for children. (Keep in mind that the biggest lead risks still come from old peeling paint and water.) Scientists found that eating one tablespoon a day of some balsamic or red wine vinegars can raise a young child's lead level by more than 30 percent.

Why do red wine and balsamic vinegars contain lead? It's unclear. It could be that grapes suck up the lead in the soil where they are grown. Another hypothesis is that lead is introduced during the process of making vinegar. The juice from the cooked grapes is stored in vintage barrels for years while it ferments and evaporates.

What can you do? Because lead levels vary depending on brand of vinegar (and even from batch to batch), it's not easy for consumers who live outside of California to know about specific products, but here are some ways to find vinegars that have the least amounts of lead.

• Aged vinegars contain more lead than the quicker brewed less expensive kinds, according to Environmental Health News. So save the gourmet vinegars for special occasions.
• Choose vinegars that do not violate California's Proposition 65 guidelines (which means lead levels are below 34 parts per billion). Some brands with products that comply include Berengo, Four Monks, Archer Farms, Regina, and Holland House red wine, although you should check this list of vinegars that have been tested and meet guidelines. O Olive Oil also makes some balsamic vinegars with low lead levels.

Environmental journalist Lori Bongiorno shares green-living tips and product reviews with Yahoo! Green's users. Send Lori a question or suggestion for potential use in a future column. Her book, Green Greener Greenest: A Practical Guide to Making Eco-smart Choices a Part of Your Life is available on Yahoo! Shopping and Amazon.com.

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