The food sampling was done in households selected for this purpose in each village. In these households, about 1 kg of sorghum (white or red) was sampled in clean new polyethylene plastic bags to avoid any contamination. For meals sampling, the selected households were asked to prepare a sorghum based dish (tô or porridge) according to their habits. All samples were put into icebox for transportation to the IRSS laboratory where extraction and analyses was done.