bad news bears a ton of spices are full of lead (consumer reports has some info but it’s partially paywalled) so is that 1984 Garfield mug and most fiber sources and anything brightly colored from before 1978 (4 yrs after women were allowed to get credit cards in their name) and many water bottles with a vacuum sealed interior due to leaded solder or some shit
I think it was lead and cadmium with the Shrek drinking glasses from the 2000s, both chemicals are commonly used to paint glass mugs. This is not exclusively a McDonald's issue, but also applies to other painted glasses (Holiday souvenirs, Sports club Merch, other drinking glasses and mugs made in china).
You might be able to buy a set of paper test strips for less than $10, but more accurate results from a lab are more expensive.
I was just replying tongue-in-cheek to this, though I really do have the cups.