Food surveillance in the Basque country (Spain) I. The design of a total diet study.

A total diet study has been initiated in the Basque country (Spain), the purpose of which is to provide estimates of the average intake of both food contaminants and certain nutrients. The types and quantities of foods that make up the average Basque 'Total Diet' are based on the results of surveys carried out between 1988 and 1990. These surveys have identified the major items in the national diet (91 categories of foods) which are combined for the total diet study, for analysis, into 16 groups of similar foods. Each group is being analysed for selected contaminants of concern which initially are: heavy metals (mercury, lead, cadmium and arsenic), organochlorine pesticides (HCB, HCH (alpha, beta, gamma, delta), DDT (DDE, TDE), dieldrin, aldrin, endrin, heptachlor, heptachlor epoxide, endosulfan and methoxychlor) and selected trace element nutrients (zinc, selenium and iron). In the milk and dairy products groups an assessment of aflatoxin M1 contamination is also being carried out.