It's common in many spices we use today, unfortunately. Consumer Reports published tests on this recently, following-up on other studies, and they have a campaign to get the FDA to regulate heavy metals because so few companies test. Fortunately, you can find brands that do independently test on Amazon, and some brands seem better than others (ie. Simply Organic).
Worse, there are unacceptable lead levels in the glazing of any dishware coming from China (which is most of it). These are levels considered unsafe for children by FDA standards (which aren't as stringent as EU standards).
There are very few safe brands in this regard. One from France and one from Turkey, at least on the US market.
The brand we settled on was Pillivuyt (better quality). You can get Corelware for cheaper that seems to be tested safe, but if you're looking for stuff that's going to last, you want actual porcelain dishware.
The other brand that we found was sold by Sur La Table, made in Turkey.
We chose porcelain over some other materials (like glass) because it's more durable, and Pillivuyt has been making the stuff for a long time (simple, high quality).
You will not find this brand among her recommendations, but my wife went to the trouble to research stated lead levels in glazing processes from a number of manufacturers. There are differences in their lines, as well. The ones you get direct from France, or through Nordstrom are the "good" lines and the William Sonoma lines are cheaper (for Pillivuyt).
That's nuts. Why are heavy metals even showing up in these? Are the herbs/spices just picking the metals up from the soil and then they become concentrated because of the drying? Do plants end up concentrating heavy metals in the seeds?
https://www.consumerreports.org/food-safety/your-herbs-and-s...