Abstract: In an assessment of the extractability of metals in
green liquor dregs from the chemical recovery circuit of semichemical
pulp mill, extractable concentrations of heavy metals in
artificial gastric fluid were between 10 (Ni) and 717 (Zn) times
higher than those in artificial sweat fluid. Only Al (6.7 mg/kg; d.w.),
Ni (1.2 mg/kg; d.w.) and Zn (1.8 mg/kg; d.w.) showed extractability
in the artificial sweat fluid, whereas Al (730 mg/kg; d.w.), Ba (770
mg/kg; d.w.) and Zn (1290 mg/kg; d.w.) showed clear extractability
in the artificial gastric fluid. As certain heavy metals were clearly
soluble in the artificial gastric fluid, the careful handling of this
residue is recommended in order to prevent the penetration of green
liquor dregs across the human gastrointestinal tract.