Determination of heavy metals in foods by anodic stripping voltammetry after sample decomposition with sodium and potassium nitrate fusion.
A method is described for the simultaneous determination of several heavy metals in foods. The sample is predigested with nitric acid and decomposed completely by heating with a mixture of sodium and potassium nitrates. The resultant melt containing the metals is then dissolved in dilute nitric acid. After the pH is adjusted to an appropriate value, the metals, such as cadmium, copper, lead, and zinc, are determined by anodic stripping voltammetry. The average recoveries of these metals added to 5 commodities were 98, 98,96, and 104%, respectively. The relative standard deviations, based on data from analyses of a commodity containing measurable levels of copper, lead, and zinc, were 12.0, 13.0, and 9.7%, respectively.
D002104:Cadmium / Q000032:analysis; D003300:Copper / Q000032:analysis; D004563:Electrochemistry; D005506:Food Contamination / Q000032:analysis*; D007854:Lead / Q000032:analysis; D008670:Metals / Q000032:analysis*; D008722:Methods; D009566:Nitrates; D014675:Vegetables / Q000032:analysis; D015032:Zinc / Q000032:analysis
D008670:Metals; D009566:Nitrates; D002104:Cadmium; D007854:Lead; D003300:Copper; D015032:Zinc