Carry-over of dioxins and PCBs from feed and soil to eggs at low contamination levels

In order to study the relationship between dioxin and PCB levels in feed and eggs, laying hens were fed with compound feed containing six different levels of dioxins, dioxin-like PCBs and indicator PCBs for a period of 56 days. This was followed by a period of another 56 days on clean feed.Data were successfully modelled in order to predict the levels after different exposure scenario’s. Overall, these data show that exposure to dioxins and dioxin-like PCBs rapidly results in increased levels in eggs and that the current EU limit for feed cannot guarantee egg levels below the EU-limit. Therefore, dioxin levels in chicken feed should be as low as possible and the current limit for dioxins in feed should be further reduced, at least in the case of chicken feeds. More in general, it is important to further harmonize the tolerance limits for feed and edible products like meat, eggs and milk. Information about the carry-over of contaminants in farm animals is essential for this purpose.