The data obtained by aqua regia extraction showed that the lead concentration of most sample sranged from 5500 mg/kg to 6000 mg/kg, and the mean concentration was 5844.2 mg/kg 7433.9 mg/kg.
The data obtained by aqua regia extraction showed that the lead concentration of most sample srangedfrom 5500 mg/kg to 6000 mg/kg, and the mean concentration was5844.2 mg/kg 7433.9 mg/kg.