> Mercury is an element so even if it gets broken down into other forms that are less toxic, isn't it still present and not "cleared" as the article claims? Are the new molecules less volitaile/unlikely to revert to their toxic organic forms or more liekly to drain off into waterways?
I have zero specific knowledge, but I can talk about the kind of thing that's generally happening with poisons.
Mercury is extremely toxic. That is probably because various of your enzymes respond to it as if it were a different organic chemical, and use it as a building block in important molecules that they are responsible for building. (It might also be because mercury naturally reacts with important molecules, expelling important functional parts and taking their place. In either case, you're left with defective functional molecules that have useless mercury where they were supposed to have something important.)
Since mercury is an element, it can't be broken down into other forms. But it can be used to build compounds that include mercury atoms. You then have the question of whether these compounds are toxic in the same way that elemental mercury is, whether because they are still (wrongly) recognized as a substitute for something else, or because they still react with proteins to replace important parts of the proteins with mercury atoms, or because the compounds react with something else in the body in a way that ejects their mercury atoms (leaving those atoms free to do their toxic thing).
The goal would be to form mercury compounds that are (1) chemically stable, trapping the mercury atoms; and (2) biologically inert. Ideally those compounds would then either filter through the digestive tract and be excreted in feces, or they'd make their way into the bloodstream, get filtered out by the liver/kidneys, and be excreted in urine.
I have zero specific knowledge, but I can talk about the kind of thing that's generally happening with poisons.
Mercury is extremely toxic. That is probably because various of your enzymes respond to it as if it were a different organic chemical, and use it as a building block in important molecules that they are responsible for building. (It might also be because mercury naturally reacts with important molecules, expelling important functional parts and taking their place. In either case, you're left with defective functional molecules that have useless mercury where they were supposed to have something important.)
Since mercury is an element, it can't be broken down into other forms. But it can be used to build compounds that include mercury atoms. You then have the question of whether these compounds are toxic in the same way that elemental mercury is, whether because they are still (wrongly) recognized as a substitute for something else, or because they still react with proteins to replace important parts of the proteins with mercury atoms, or because the compounds react with something else in the body in a way that ejects their mercury atoms (leaving those atoms free to do their toxic thing).
The goal would be to form mercury compounds that are (1) chemically stable, trapping the mercury atoms; and (2) biologically inert. Ideally those compounds would then either filter through the digestive tract and be excreted in feces, or they'd make their way into the bloodstream, get filtered out by the liver/kidneys, and be excreted in urine.