Binders is a topic long studied in a few different ways. First, animal studies that often look at excretion of toxic compounds in the urine and feces. Next is far fewer human studies in excretion in humans of compounds. All urine based toxicity tests are excretion tests and do not necessarily represent body burden. The only body burden tests that don't involve biopsy (which is localized / not practical) are blood plasma tests for toxins that remain only in the blood and don't get stored in the body (benzene, as one example).
Alternatively, I prefer to study the mechanism of action to understand efficacy. In the case of binders this comes to a few key elements: 1) Charge or polarity; 2) Number of right sized binding sites on the binder for the toxin in question; 3) surface area - is it a large charcoal briquet or is it finely ground takesumi charcoal powder; 4) pH effects in the gut have some research that change the polarity / charge of the binder in question.
First - take charcoal and chitosan - totally opposite in charge so they attract different toxins; without polarity - the toxin doesn't stick to the binder. Or take modified citrus pectin - a fantastic fit in terms of right sized binding sites for lead - but polarity is not so strong - so you need to continually take it to drag it out of the gi tract. Second, This is super important - number of right sized binding sites - this is where things like silica matches great for mercury - where like lego blocks the molecules fit together (the polarity keeps them stuck together), and cholystyramine / chitosan matches great for ochratoxin a - alot of binding sites of the perfect size. You need to understand some basic molecular chemistry to dig in here. Three Surface area - this is where marketing can skew things, you will hear '1 serving of micronized silica has as many binding sites as 300, 200mg chlorella tablets". True, but if you compare micronized chlorella to micronized silica its a more apples to apples comparison, that still favors silica, but not as much. Similarly comparing a charcoal briquet to charcoal powder. This is where takesumi charcoal can claim 20% better binding that normal charcoal - its a more finely ground charcoal which exposes more binding sites. The pH arena is less studied and seems to apply primarily to the DE and clays of the world, where modification of the gut pH can alter the charge of some of the binding elements in the gut. Lastly, if you look at the most respected scientists and broadest coverage binders on the market (namely, Biobotanical Research GI Detox and QuickSilver Ultrabinder - they have a mix of different binders of different charges and different sized binding sites. Before Chris Shade at Quicksilver came out with UltraBinder, he included the GI Detox binder in his detox kits. GI Detox was created by a well known and well respected research and scientist in this space. Chris then added Chitosan (for ochratoxin A specifically) and his patented micronized silica for his specialty in dealing with mercury toxicity. In practicality, what i have observed is that after you get into detox, you may drag out primarily one toxin in the beginning (like ochratoxin A), but as the binders in the gut signal to the rest of the body to release toxins at the cellular level - a variety of stored toxins get released, typically from fat stores - and this is a soup - and where a mix of binders can be helpful - and a mix of supports for the different phase 2 liver conjugation pathways.
I will also add, if you start taking large doses of a binder with a large number of right sized binding sites for a toxin you loaded with (cholystyramine = ochratoxin A, or mercury = micronized silica) ; I have observed clients becoming overwhelmed , specifically their liver, because the phase 2 detox conjugation pathways need support to process these; as well as phase 2.5 - BSEP / MRP2 , the bile salt export pump. Without supporting these critical elements first, you are asking for a "herx" reaction which is when the liver becomes overwhelmed, protects MRP2 by shunting bile to the blood instead of to the gallbladder, where it hits the brain and kidneys (headaches, neuro issues, lower back pain, itchy skin).
So, this leaves us, what binders are good for what !:)? In a separate article on this blog i will post some of these reference tables. For now, if you are looking for an all in one binder, there are two i like: GI Detox by Biobotanical Research, and UltraBinder by Quicksilver Scientific. I also deploy charcoal, chlorella, chitosan, bentonite clay, DE, IMD, Okra, Modified Citrus Pectin (with and without algae), silica, micronized silica, micronized chlorella, Carboxy, Biotox, and rice bran fiber. I do find that some portion who are in a 'sensitive phase', cant tolerate the all in one blends. For this reason i start with individual ones first, unless the client has already informed me they have tolerated one of those blends. Binder selection is informed by : known exposure, toxicity panel results, GI related issues, genetic issues (so i don't trigger a flood of certain toxins that compromised phase 2 pathways cant handle), and the clients reactivity / stability.