Review of aspects pertaining to food contamination by polychlorinated dibenzodioxins, dibenzofurans, and biphenyls at the farm level

The recent concern on polychlorinated dibenzodioxin (PCDD), dibenzofuran (PCDF), and biphenyl (PCB) presence in the food chain has been determined mainly by the use of contaminated feeds, marketed on a large scale. As a consequence, the regulatory authorities of the European Union (EU) have defined different contamination threshold levels for the compliance of both marketed feeds and foods, thus, pushing national authorities to activate specific monitoring plans. At farm level, the presence of small sources of contamination could be of some impact. Therefore, this article provides a review of factors that could be included in a Hazard Analysis of Critical Control Points (HACCP) system to possibly abate accumulation in the food chain of the aforecited contaminants. Such system could be particularly relevant in the near future, due to the EU agriculture policy trend towards non-intensive and/or organic farms, characterized by a self-supply of animal feeds. In this paper, the main microsources of PCDDs, PCDFs, and PCBs at farm level are discussed, as well as the relevant factors determining their spreading and bioaccumulation along the food chain. This is a preliminary step for the development of appropriate monitoring strategies and teaching/training of interested stakeholders.