[pbnjeh]

Exposure to cigarette smoke was also considered a candidate or reason, when I was younger. I haven't kept up with the thinking on or about this, but I believe it's still considered valid.

Remember, a few decades ago, a lot of the "Western" world smoked, including in public spaces and around kids. As I understand it, a lot of the rest of the world has caught up and still does so. And the Western world isn't exactly rid of the behavior, either.

P.S. I wonder whether anyone's studied possible multiple-generation, genetically-communicated knock-on effects of this.

P.P.S. "Pollen" is also a Racket language based blogging and authoring tool or environment. A bit sorry to see the name become overloaded.