What to do with Excess ApihP, MDPiHP, 4MMC and other RC benzos and tryptamines

I ended up stockpiling a pretty ridiculous amount earlier this year — partly out of paranoia, partly out of habit. I kept thinking there’d be a shortage, or my vendor would disappear overnight, so I grabbed more than I’d ever realistically use.

But life has a way of flipping the script. I landed a job that’s pulling me all the way to Switzerland, and with that comes a clean break. I’m not flying with any of this, and honestly, I’m stepping out of the RC world entirely.

Now I’m stuck with about 40g that I have zero intention of keeping. If I flush it, am I risking plumbing chaos? And if that’s not the smartest move, what’s actually the safest way to get rid of these chems for good?
Thank you