The most common persistent organic pollutants (POPs) occurring were Dichlorodiphenyl trichloroethane (DDT) and its metabolites (found in 21 % of samples tested in 1998 and 22 % in 1999), and dieldrin (found in 10 % of samples tested in 1998 and 12 % in 1999) while residues of fi ve and more chemicals could be occurring in a single food item (Schafer