I was remembering this: https://www.wired.com/2000/02/coffee-is-your-friend/ https://www.wired.com/2000/02/coffee-is-your-friend/ "A group of international sci

I was remembering this: https://www.wired.com/2000/02/coffee-is-your-friend/ https://www.wired.com/2000/02/coffee-is-your-friend/ "A group of international scientists found that coffee filters can remove from 78 to 90 percent of dissolved heavy metals such as lead and copper from tap water." It looks like the quote is incorrect though, and it is actually the the ground coffee and not the paper filter that's removing the lead. Regardless, brewing ground cacao in the same way would likely also filter out some of the lead by the same mechanism, even if not as much. (Since the source of lead is embedded throughout the ground beans, rather than coming from the water which enters at the top of the column.)