Exposure  assessment

Estimates of dietary intakes of food additives, residues of pesticides and veterinary drugs and contaminants require information on the consumption of relevant foods and the concentrations of the chemical of interest in those foods.  In general, three approaches are available in exposure assessment: (1) total diet studies (2) selective studies of individual foods, and (3) duplicate portion studies. Guidelines for the study of dietary intake of chemical contaminants are available from WHO. In recent years, direct monitoring of human tissues and  body  fluids has been  increasingly used  to assess exposure. For example,  the determination  of levels of organ chlorine  compounds in  breast milk, which are mainly  derived from  the diet, has  provided  an  integrated assessment of  human exposure  to  these substances.