This material was prepared by adding solutions containing cadmium, lead and tin to a commercial tomato paste. The natural levels of cadmium, lead and tin were determined in the paste prior to spikinmg to allow the calculation of the quantity of elements to ad, The final concentrations of the three elements in the paste were chosen to be representative of legislative limits.
The material was mixed thoroughly and dispensed in 50 g portions into acid-cleaned glass bottles with tamper evident tops. The filled bottles were irradiated at a dose of 14-18.3 kGy, and stored frozen at -20°C.
The homogeneity of the packed material was also assessed for total solids content. Ten units from across the filling run were selected and analysed in duplicate. The material was judged to be homogenous as the variation between the samples tested was not significantly greater than the method variation. The mogoneneity was assessd using a sample size of 2 g.
This material is intwended for use in the validation of methods of tin, lead and cadmium in a fruit or vegetable based material. It may also be used for monitoring the on-going performance of a method.
Keywords: Biological material, Plant material, Foodstuff, Agricultural food product, Heavy metals, Trace elements,