Many people get osmosis backwards: it’s the solvent (eg water) that moves…not the solutes! In other words, osmosis can only suck things dry, but it cannot suck “stuff” (eg toxins) out of anything. This ancient point of confusion has now been made even clearer in a minor update to the Epsom salts article, along with some details about what can get through skin and what can’t and why (e.g. 500 Dalton rule, which is neat). Maybe this will put a stop to the weird osmosis-confusion e-mail I’ve been getting for a decade? Yeah, probably not.