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.
Rainer Zenz / Wikimedia Commons