No acute risk to health from dioxin in eggs
Since the beginning of the year the same maximum level for dioxin has applied to eggs from free-range hens as did previously to eggs from battery hens. Consequently, with immediate effect, one kilogram of yolk fat may not contain more than three nanograms and one gram of yolk fat no more than three picograms of dioxin (an egg contains round 10% fat). Evidently, this maximum level has been exceeded in some cases. BfR is of the opinion that the occasional consumption of these eggs does not pose an acute threat to health. Compared to other foods of animal origin like milk, meat or fish the eggs only raise the total daily intake of dioxin insignificantly. Since, however, the dioxin intake by human beings is still higher than the precautionary health value aimed for by the World Health Organisation, BfR considers that there is an ongoing need for all measures which can effectively reduce overall exposure.
Dioxins are ubiquitous. They are formed during incineration processes. They are also of significance even today as contamination left behind in the ground from earlier industrial production. The group of dioxins encompasses a large number of substances with very different potentials to harm health. Some can trigger cancer. That’s why there are efforts around the world to minimise exposure. The World Health Organisation states the intake level which should not be exceeded daily on precautionary grounds as 1 picogram dioxin equivalents per kilogram body weight and day (1 pg/kg bw/day) and the tolerable daily intake as 1 to 4 pg/kg bw/day. Dioxin equivalents encompass not only polychlorinated dibenzodioxins but also dibenzofurans and polychlorinated biphenyls which almost always occur together.
Examinations of human milk and foods show that dioxin exposure has fallen by more than half over the last ten years. However, average daily intake is still almost 2 pg/kg body weight and day and thus continues to be above the precautionary value aimed for by WHO.
Free-range hens can take in dioxins when pecking in the ground for food. Dioxins can then be found, for instance, in the eggs and because of their fat solubility mainly in yolk fat. The amount of dioxin in eggs seems to be very closely linked to regional soil contamination. The dioxin levels in most eggs from free-range hens only differ marginally from those of battery hens. But there are cases where far higher dioxin levels have been detected in eggs. There were peak values of 20 and more ng per kg yolk fat.
BfR already published its opinion on the risk from dioxins in eggs in April 2004. At that time, the Institute advised against extending the exemption for free-range eggs. It was indeed the case that BfR did not consider that the occasional consumption of eggs containing more than 3 ng dioxin per kg yolk fat, which thus exceeded the maximum admissible level, posed a health risk to consumers. At the same time, however, the Institute pointed out that it felt it was necessary to apply the maximum level to all eggs in order to further reduce the total exposure to dioxins.
In the opinion of BfR there is no need at present to forego eating free-range eggs since in general they only account for a comparatively small proportion of man’s exposure to dioxins from food. Highly contaminated eggs are the exception. They should not be eaten. This recommendation also applies to people who keep their own hens.
Further information on this subject can be accessed on the BfR homepage under Foods/Food safety/Residues and Contaminants.