Estimation of mercury burdens in rats by chelation with dimercaptopropane sulfonate

The chelation of mercury by 2,3-dimercaptopropane-1-sulfonate (DMPS) and its usefulness in the estimation of mercury burdens was investigated by exposing male, Sprague-Dawley rats to ²⁰³HgCl₂ (0.1-2 mg of Hg per kg i.p.) or ²⁰³Hg vapor (0.5-2.0 mg of Hg per m³). DMPS (0.2-2.0 mmol/kg) was injected i.p. at times ranging from 1 to 38 days after exposure to the mercurial. Urine and feces were collected for 24 hr before and after DMPS treatment. Whole body mercury levels, tissue levels and excretion of mercury were measured by radioactivity counting. Afting DMPS treatment there was a significant decrease of whole body mercury levels and an increase in urinary excretion. The increase in urinary excretion was directly proportional to the whole body burden of mercury at the time of dosing with DMPS in animals dosed with HgCl₂ and exposed to mercury vapor. Furthermore, the increase in urinary excretion induced by DMPS was almost equal to the amount of mercury lost from the kidneys.