Contamination of chicken eggs near the Vikuge obsolete pesticides stockpile in Tanzania by dioxins, PCBs and hexachlorobenzene.
Free-range chicken eggs collected in Vikuge village and its surroundings 56 km northeast of Dar es Salaam showed elevated levels of dioxins and high levels of hexachlorobenzene (HCB). HCB levels were 2-fold higher than the newly proposed limit for HCB as a pesticide residue and were very close to the existing limit for this chemical in eggs. Dioxin levels exceeded background levels by almost 2.5-fold and were slightly higher than the European Union (EU) dioxin limit for eggs. To our knowledge, this study represents the first data about unintentionally produced POPs in chicken eggs from Tanzania. The most obvious potential source of POPs releases at the site is obsolete pesticides storage, though it could also be open burning. The measured levels of POPs were accompanied by high levels of POPs pesticides residues and both together represent a concern for wider contamination. Drinking water contamination by POPs pesticides was found previously, but unintentionally produced POPs were not measured in food until this study.