The most recent incident I could remember was some sort of dried fruit. Not sure why (improving the label's detail would help). Maybe it was contaminated with something or maybe the packaging itself was a problem. I ended up buying a different kind.
Thank you. After I wrote that, I was thinking whether I'd actually seen Prop 65 warnings on food items and I honestly can't remember. Usually I see them on the entrances to buildings. I'm sure Whole Foods has a Prop 65 warning by their front door.
Oh? Please explain how it costs you, the consumer? Or how it annoys you other than in a purely free-market theoretical way?
Sure, I'll give you three. Bear in mind we're talking about a proposition. Being annoyed is sufficient reason to vote for or against one.
Say you've got a bag of dried apricots. There's only so much room on the label for marketing blather, idealized images, mandated nutritional information, and the warning. My eyes aren't what they used to be but I do read the nutrition information. I'd rather the nutrition facts were larger and easier to read rather than having the Prop 65 warning.
The apricot packager has compliance costs. They need to have some people who track the ever growing list of prop 65 chemicals to see which items need the warnings and which do not. They need people to track whether the label requirements have changed, in terms of size, placement, fonts, and whatnot. That isn't free and needs to add a (admittedly small) cost to the package of 'cots. Multiply that by the thousands of products you buy every year and the millions of consumers in California. Granted it would be quite hard to measure the actual cost but it's not zero.
Finally there are lawsuits. I just checked, the number of them in increasing over time, abut 3,400 in 2023. If the proposition was having it's intended effect, by now you'd expect the number to be going down (as producers learn to just not include the offending chemicals). Settling these suits costs money and that money comes from consumers (via increased costs) or investors (via lower ROI). I have a noticeable amount of my retirement savings invested in stocks, and you may too, which means we're paying for those settlements.
You might dismiss the last two as "purely free-market theoretical" issues but I do not. They're good examples of concentrated benefits, distributed costs. It would be difficult to accurately quantify the costs but we can pretty confidently say it's not zero.