Levels of calcium, magnesium, manganese, zinc, selenium and chromium in olive oils produced in Andalusia.

We determined the presence of Ca, Mg, Mn, Zn, Se and Cr in 64 samples of ol ive virgin oil, olive oil and marc oil produced in Andalusia; southern Spai n. Flame atomization atomic absorption spectroscopy was used for Ca and Mg, and the electrothermal atomization mode was used for Mn, Zn, Se and Cr. Sa mples were previously ashed with HNO3 and V2O5. Analytical conditions were optimized to control for interference and to obtain appropriate accuracy an d precision factors. The method is potentially useful for quality control o f olive oils. The concentrations ranged from 0.055 to 2.725 mg/kg for Ca; 0 .300 to 5.300 mg/kg for Mg, 13.213 to 296.356 mug/kg for Mn; 8.758 to 36.57 5 mug/kg for Zn, undetectable to 178.515 mug/kg for Se, and undetectable to 41.510 mug/kg for Cr. No statistically significant differences were found between the three types of oil in the concentrations of these elements. The re were significant correlations between the concentrations of the pairs Se -Cr, Mn-Cr, Mg-Zn, Ca-Zn and Ca-Cr. Because of the high intake of olive oil in our setting, this food can be considered a major source of essential el emental nutrients.