Considerations for the regulation of polychlorinated dibenzodioxins, furans (PCDD/Fs) and biphenyls (PCBs) in liver

Abstract

Introduction There is increasing evidence that liver produced from farm animals such as cows, pigs and sheep may breach European Union regulatory limits for dioxin concentrations even when the livestock are given compliant animal feed and are exposed only to normal background levels of dioxin contamination in the environment. The dioxin concentrations in other commonly consumed tissues such as muscle, fat, kidney, etc., from the same animals will typically be well within regulatory limits. When dioxin limits were initially proposed and eventually established by the European Union, almost a decade ago, they were based on a small data set available at the time, and were expressed on the basis of concentrations in fat in common with limits for other animal products (except for fish which were set on a whole weight basis because of seasonal and other variations in the lipid content of this species). Data generated for liver since the regulations came into force, suggest that dioxin concentrations in liver from certain types of animal are higher than were anticipated. Objectives We set out to establish whether liver on retail sale produced using normal farming practices was likely to contain dioxins and polychlorinated biphenyls above regulatory limits and to consider whether or not the regulations were appropriate. Method We did this by analysing samples of liver obtained from retail outlets. Results and Conclusion Nine of the 22 ovine (sheep) liver analysed and reported here exceeded the European Union limit for liver and all 10 of the venison liver exceeded this value, although venison liver is not covered by the regulation. The high cost of compliance monitoring, together with the likely proportion of non-compliances, could amount to a de facto ban on the sale of ovine (sheep) liver even in the absence of a risk to consumer health. The preferred solution would be to revise the existing dioxin and total TEQ limits set out in Commission Regulation (European Commission) No. 1881/2006 to reflect the levels that are normally found, with the addition of precautionary advice to consumers if this is considered necessary.