Dioxin, in chicken

The accidental contamination of chicken feed with dioxin contaminated fat in Europe shows how food exposure could occur. Because dioxin does not cause immediate symptoms, authorities did not discover the contamination for months in 1999, and Europeans probably consumed the dioxin in chicken meat and eggs sold that year. One lesson learned from this event is that physicians and public health officials need to recognize and report unusual or suspicious health problems in animals as well as humans (1). The 1999 West Nile virus epidemic in birds and humans in New York City reinforced this lesson. Fortunately, biological and chemical contamination of public water supplies will usually pose little risk due to dilution by the large volume of water. 

Bruggeman, V., Swennen, Q., De Ketelaere, B., Onagbesan, O., Tona, K. and Decuypere, E. (2003). Embryonic exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin in chickens effects of dose and embryonic stage on hatchability and growth. Comp. Biochem. Physicol. C Toxicol. Pharmacol. 136, 17—28. 

Absence of ecotoxicity and total biodegradability are the most important properties for public administrators and legislators, especially after the recent cases of the mad cow disease and the presence of dioxins in chickens. Build up of biodegradable plastics, spread in the agricultural soils year after year, would not be acceptable. 

What about the public administrators, the legislators, the politicians Since public health and food production could be affected by a massive application of biodegradable plastics in compost, the public administrators indubitably prefer any option increasing safety rather than decreasing it. This is particularly true after the recent case of the Mad Cow disease and the presence of dioxins in chickens. Summarizing very low heavy metals content, no ecotoxic effects, no plastic residues, visible or invisible, brought in the field together with compost. 

A consistent pericardial edema in chickens gave rise to the term chick edema disease (chick edema factor) (I). Two known outbreaks of the disease in the broiler industry resulted in a great loss of chickens. A lipid residue from the manufacturing fatty acids, being used as a feed ingredient, was a principal source of the toxic substance. Contamination of the lipid component with polychlorodibenzo-p-dioxins was attributed as the causal agent. 

Ryan JJ, Pilon JC. 1982. Chlorinated-dibenzodioxins and dibenzofiirans in chicken litter and livers arising from pentachlorophenol contamination of wood shavings. In Hutzinger O., ed. Chlorinated dioxins and related compounds Impact on the environment. New York, NY Pergamon Press, 183-189. 

Eerrario J. and Byrne C. (2000) The concentration and distribution of 2,3,7,8-dibenzo-p-dioxins/-furans in chickens. Chemosphere 40, 221-224. 

Pentachlorophenol-contaminated air, rain, snow, surface waters, drinking waters, ground-waters, and aquatic biota are common in the United States. Residues of PCP in food, water, and mammalian tissues may result from the direct use of PCP as a wood preservative and pesticide or as a result of use of other chemicals that form PCP as degradation products - i.e., hexachlorobenzene and lindane. To confound matters, PCP was judged to be the source of dioxin and dibenzofuran contamination in chickens in Canada. More than 50% of all chickens sampled contained hex-achlorinated dibenzo-p-dioxins (hexa CDDs) at concentrations of 27.0ng/kg fat and higher ... 

In ovo exposure to dioxins is associated with development of grossly asymmetric avian brains, especially the forebrain and tectum. Brain asymmetry was observed in herons, cormorants, eagles, and chickens exposed to 2,3,7,8-TCDD under controlled conditions. Asymmetry appears with increasing frequency and severity in embryos and hatchlings exposed to increasing doses of... 

Ryan, J.J., R. Lizotte, T. Sakuma, and B. Mori. 1985. Chlorinated dibenzo-p-dioxins, chlorinated dibenzo-furans, and pentachlorophenol in Canadian chicken and pork samples. Jour. Agric. Food Chem. 33 1021-1026. 

Harnly, M.F., Petreas, M.X., Flattery, J. and Goldman, F.R. 2000. Polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran contamination in soil and home-produced chicken eggs near pentachlorophenol sources. Environmental Science and Technology 34 1143-1149. 

In several European countries, higher dioxin levels have been reported in eggs of free-range chickens, compared to chickens kept indoors (DeVries et al., 2006). High levels were found mostly on smaller farms, possibly because the chickens made more extensive use of the outdoor run. Plants appeared to be a relatively unimportant source of dioxins, as well as commercial feed. It was concluded that the high dioxin levels were related to the consumption of worms, insects and soil. 

Goldman LR, Hayward DG, Flattery J, et al. 1989. Serum, adipose, and autopsy tissue PCDD and PCDF levels in people eating dioxin-contaminated beef and chicken eggs. Chemosphere 19 841-848. 

Kennedy SW, Lorenzen A, Norstrom RJ. 1996. Chicken embryo hepatocyte bioassay for measuring cytochrome P4501A-based 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalent concentrations in environmental samples. Environ Sci Technol 30 706-715. 

Ryan JJ, Lizotte R, Sakuma T, et al. 1985b. Chlorinated dibenzo-para-dioxins, chlorinated dibenzofiirans and pentachlorophenol in Canadian chicken and pork samples. J Agric Food Chem... 

Fish eaten by people residing in northern Norway are contaminated with PCBs, chlorinated pesticides, and their metabolites. Fish living in mangrove habitats in Singapore are contaminated with polybrominated diphenyl ethers (PBDEs). I5 Dioxins and PCBs are found in the eggs of free-range chickens. 

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