Short term exposure isn&#x27;t much of an issue, unless you inhale or ingest it. (Simply playing with it isn&#x27;t going to send out massive amounts of vapor; it&#x27;s not super volatile.) The real fear is that it seeps into a hard to clean place and provides a steady stream of vapor over a long time.... basically what the OP illustrated about his house.<p>Previous generations had no qualms playing with it or lighting it on fire in science class. While it might not have been super healthy, we also don&#x27;t have a generation of mad hatters.