Test method validation for quantitative determination of heavy metals in olive oils by inductive coupled plasma (ICP-AES)‎ using low cost and simple extraction method

Abstract EN

The aim of this study is to demonstrate a valid and simple extraction method for the extraction of heavy metals from olive oil and its quantitative determination by ICP-AES technique.

Fifteen olive oil samples are collected from different manufacturing companies originates from five countries.

Fourteen metals are quantitively detected in all samples including; Aluminum, Arsenic, Calcium, Cadmium, Cobalt, Chromium, Copper, Iron, Potassium, Magnesium, Manganese, Nickel, Lead and Zinc.

A simple extraction method has been proposed for the extraction of heavy metals from the raw oil samples based on diluted 10% HNO₃.

Test method validation procedures have been carried out for the quantitative analytical determination of the detected trace metals in the investigated oil samples.

The trace elements are found to be in the concentration range from 0.0001 to 8.39 mg.

kg^-1.

As a result of the test method validation; linearity (R2) is above 0.99, the recovery ranged between (72.63% to 124.62% ), the limit of detection and the limit of quantitation are between (0.006– 2.32 µg.

kg^-1) and (0.022 – 7.68 µg.

kg^-1) respectively.

The relative standard deviation (RSDs) for repeatability and ruggedness are found to be lower than 2.2% for selected elements, which confirms the precision of the ICP-AES analytical method.

The results demonstrate the validity of accurate, precise, rugged, selective, specific and stable ICP-AES determination method for trace metal analysis in raw olive oil samples that based on the proposed simple extraction method.