Lake sediment - Trace elements
Certified values
As............................. 33.4 mg/kg    Cr ............................... 126 mg/kg    Ni ................................ 69 mg/kg
Cd ............................ 0.85 mg/kg    Cu ................................ 53 mg/kg    Zn .............................. 224 mg/kg
Co ............................ 16.8 mg/kg    Hg ............................. 1.46 mg/kg