What primary source characterizes why Prussian blue's lattice selectively binds monovalent Cs+/Tl+, and what are the measured biological half-life reductions?

The question

claim-prussian-blue-is-the-fda-approved-antidote-for-radioactive-cesium-and-thallium states the general decorporation mechanism (gut ion-exchange sequestration) on a Tier-1 HHS/REMM source, but two finer points are not yet sourced to a primary:

1. The physical-chemistry explanation of why the porous ferric-hexacyanoferrate lattice selectively traps monovalent Cs⁺/Tl⁺ over competing cations (ionic radius / lattice-site fit / hydration-energy arguments).
2. The quantitative reduction in biological half-life. Search-mediated figures seen at capture time (Cs ~110→30 days; Tl ~8→3 days) were not re-verified against a primary and were deliberately kept out of the claim-note body.

Why it matters

Specific technical-mechanism claims and quantitative claims both require Tier 1–2 sources (sources.md sourcing floor). The mechanism and the numbers currently sit below that floor, so they must not be promoted into the note as verified.

What would answer it

• A primary pharmacology/toxicology paper or the FDA Radiogardase label/review characterizing cation selectivity and reporting half-life reductions with measured values.
• A peer-reviewed review of Prussian blue decorporation kinetics.

Until answered, the mechanism detail and half-life figures stay out of the claim-note's hard claims and the note stays status: seedling.