Aluminium occurrence in plant feed from Northwestern Italy.

Background: Aluminium (Al) is widespread in nature, but the main route of exposure for humans and animals is through food. Cereals and vegetables give and important contribute to dietary intake. This investigation focused on the occurrence aluminium in raw materials intended for animal consumption. In fact, Al is not included in the official monitoring programs, and little or no data are still available about its presence in feed or plant material.

Methods: Rice, wheat, corn, barley, rye, triticale, oats, and soy samples were collected in Northwestern Italy in an area characterized by clayey soil rich in aluminium silicates. Samples were subjected to homogenization and microwave acid digestion and Al was quantified by Inductively Coupled Plasma-Mass Spectrometer (ICP-MS).

Results: Different aluminium concentrations were found in the analyzed raw materials: soy (89 mg kg) > rye > rice > oat > triticale > barley > wheat > corn (2.9 mg kg). In this study, Al concentrations were found higher than those reported for same matrices in other UE and non-EU countries, especially in rice and soy.

Conclusions: Al concentrations were related to the soil geological feature and to the physiological characteristics of the plant species. These two factors must be carefully considered for a reliable evaluation of aluminium exposure through feed and food.