Dr. Bill: The signs in our stores in California are due to the miss-wording of Prop. 65 years ago.
Prop. 65, rather than using the established limits for exposure to certain chemicals, stated any detectable levels of chemicals know to cause cancer, etc. Since even apples and oranges have detectable limits of carcinogens and teratogens, not to mention outright poisons such as arsenic,
every apple, orange, peach, etc. would have had to carry that label. Grocery stores won an amendment in the legislature that a single label on the door would suffice. Since the Prop. 65 was a ballot initiative, it would require a public vote to overturn it.
Virtually all lead contains detectable levels of mercury and a few other heavy metals, so, the Prop. 65 label has to be on the wall. That same label is on the side of the gas dispenser at the gas station and all sorts of other places, too.
Just another result of the lack of science education in our schools... <sigh>
Ian