Probably not, but I’m not a scientist or biologist so this is purely a guess from me, but you have to consider the fact that you’re not combusting anything containing the heavy metal in something like a nasal spray like you are when smoking.
I can’t imagine combusting any plant material containing a measurable amount of any heavy metal & inhaling it is good for the lungs & would assume that’s part of why in legal countries like Canada, the governing bodies (in our case, Health Canada) mandate heavy metal testing of licensed cannabis producers’ dried flower.
Edit; wow, didn’t realize I was replying to a post from months ago. Sorry if this is now irrelevant. Still, don’t smoke your plants treated with CS or STS folks. I like you all too much, and that seems like a very bad idea.