Are environmental pollutants in the Norwegian diet harmful to children?

Environmental pollutants represent a global problem and pose a threat to animals as well as humans (1). The potential for harm is especially great in periods of life when there is rapid growth and development, such as during pregnancy and childhood (2). Persistent organic pollutants (POPs) is a collective designation for a group of organic environmental toxins that include dioxins, polychlorinated biphenyls (PCBs), brominated flame retardants and organochlorine pesticides. They degrade very slowly, are scarcely excreted from exposed organisms and therefore tend to accumulate in the food chain (bioaccumulate). Most of them are fat-soluble, and the highest concentrations in our diet are found in fatty foods, especially oily fish (3), while breast milk is the main source for infants (4). During the last ten years, the level of most, but not all such environmental pollutants has declined in foodstuffs, including in breast milk (5). Many of the environmental pollutants are stored in the body’s fatty tissue, where they may have a half-life of up to ten years. With pregnancy and breastfeeding, their level in women is reduced (6). However, while the amount of environmental pollutants in the mother declines, it increases in the child, and a considerable proportion of the mother’s store of pollutants is transferred to the firstborn (7). After one year of breastfeeding, the concentration of certain environmental pollutants in breast milk may be reduced by more than 90 % (8). A recent study found that the plasma concentration of PCB in Norwegian infants was approximately 40 % higher than in their mothers. The plasma concentration in the infant was related to