Kids nowadays are drowning in plastic stuffies, which I assume are made of toxic waste. No joke, iirc they off gas enough to pick up on household air quality sensors.
Gas stoves however.. they spike voc and co2 around the house when used.
A “toxin” is a naturally occuring poison, such as snake venom. The word you're looking for is the umbrella term “toxicant”.
See: https://en.wikipedia.org/wiki/Toxicant
But, pendantry aside, pretty sure a lot of those plastic toys, especially the sort of rubbery squishy ones, are probably loaded with pthalates and other exotic and interesting things.
It's like the people dying on that pedantry hill over "literally" being now used in slang to just mean "a lot / really significantly" rather than "how something appears in literature". I'm sure there were people equally complaining about the death of the English subjunctive verb [1].
Anyway, “Toxicant” is a perfectly cromulent word.