Use of EDTA for chelating toxic metals inhibiting BOD measurements

Abstract

The trans-isomer of sodium ethylenediamine-tetraacetic acid (EDTA) was used to chelate metal ions known to inhibit accurate determination of BOD of wastewater. The results showed that as much as 5 mg Cu(II) and 6 mg Zn present in a litre of poultry wastewater were effectively chelated by 1 ml of 0·1 m EDTA so that the metals had no suppressive effect on the BOD values.