ICP-MS triple quadrupole as analytical technique for the characterization of metal contamination processes in commercial flours for food safety

This study focuses on the analysis of the elemental composition of different commercial flours focusing the attention on toxic trace metals. The goal is to search markers for contaminations, due to the growth of the cereal in polluted soil, and / or due to the working process to which the cereals are subjected to obtain flour. To do that, different kind of flour (wheat, durum wheat, oats, corn, spelt and rice) were bought and analysed using ICP-MS triple quadrupole located in an ISO 6 cleanroom. Arsenic, cadmium, and lead founded could be related to soil contamination. Vanadium is therefore identified as a useful marker of process contamination as it is commonly scarce in the soil, but it is very common in the heavy-duty milling cylinders. Poor maintenance, wear conditions, economic reasons could be some of the causes of process contamination. Finally, a possible marker for type 00 wheat flours was identified, having observed the tendency of caesium to accumulate in the internal parts of the wheat grain.