古冶炼废渣急性毒性危害试验研究

he total amount of heavy metal in ancient smelting residue was analyzed. The acute toxicity of lixivium from the waste residue was discussed. The results showed that the residual heavy metal (Zn and Pb) content in the ancient residue was up to 6.97%. After weathering and rain leaching over several hundred years, more than 1.71% of Zn and Pb had been released to the surrounding environment. The lixiviation ability of heavy metal in the ancient smelting residue has declined. Only a very small part of Zn lixiviated at a few locations, the amount of Pb leaching is below the detection limit, and only a small amount of Cr and Cd leaching occurs. According to the pre-test results, the limit test method was adopted to carry out acute toxicity tests. The results showed that acute oral LD50 (median lethal doses) in mice for the lixivium was greater than 20 mL/kg•bw. No death or abnormal behaviors of mice were observed during the experiment. However, weight gain of mice significantly decreased. After the experiment, anatomical examination was performed for mice liver and kidney. No abnormal change was found. No significant difference was identified when compared with the control group. It showed that residual heavy metal content in the smelting residue was still high. Although the lixivium toxicity declined over a long period, the acute toxicity hazard still exists.