Food contamination polychlorinated biphenyls

Where analytical methods are available it is largely because of a crossfertilisation of effort from well-established areas of food contaminants work. For example, the steady development since the 1960s of methods of analysis for chlorinated pesticides led to the analysis of food for polychlorinated biphenyls (PCBs) since PCBs were readily detectable by general methods used to analyse food for organochlorine pesticides. The analysis of food for chlorinated dioxins and furans (PCDDs and PCDFs) at the very low levels at which they are found in food is a more recent development, and one that is an important precedent since it arose from interest in environmental contamination rather than because of cross-fertilisation of scientific methodology from an established area of food chemistry. Although dioxins were detectable some years ago at much less sensitivity in some pesticides, it was environmental interest that led to their study at very low levels in the food chain. 

There is a vast range of aqueous organic pollutants with a wide toxicity profile. Some, e.g. polychlorinated biphenyls, certain herbicides, fungicides and pesticides, and organo-mercury compounds, are persistent and may bioaccumulate in the food chain. Trace contaminants such as sodium chloride, iron and phenols (especially if chlorinated) may also impart a taste to water. Typical consent levels for industrial discharges are provided in Table 13.10. 

Muir, D.C.G., R.J. Norstrom, and M. Simon. 1988. Qrganochlorine contaminants in Arctic marine food chains accumulation of specific polychlorinated biphenyls and chlordane-related compounds. Environ. Sci. Technol. 22 1071-1079. 

Polychlorinated biphenyls (PCBs) have been used in various industrial processes during the past 40 years but were not recognized as major environmental contaminants until 1966 (1). Fish as a major food source have attained the dubious honor of being the most frequently cited PCB contamination problem (2). In the following presentation disposition of PCBs in fish will be discussed from four points of view accumulation, metabolism, distribution and elimination. No attempt will be made to cover PCB residue levels found in fish in nature (3) or acute or chronic toxicity of PCBs in fish (4-20). 

Polychlorinated biphenyls (PCBs) and radioactive substances, predominantly emitted by industrial sources, are not specific to any type of farming activity. As with heavy metals, similar levels of contamination are to be expected in organic and conventional food sources. 

Food and Agricultural Organization of the United Nations, World Health Organization, Joint FAO-WHO Expert Committee on Food Additives, 57th Meeting, Rome, June 5-14,2001. Summary and Conclusions. Annex 4 Contaminants. 5. Polychlorinated Dibenzodioxins, Polychlorinated Dibenzofurans, and Coplanar Polychlorinated Biphenyls, http //www.who.int/ pcs/jecfa/Summary57-corr.pdf. pp. 24-40. 

Polychlorinated biphenyls (PCBs section 1.2) and dioxins have been most widely studied in this category. PCBs were used in a wide variety of industrial applications, for example as dielectrics in transformers. But they are very persistent contaminants, both in the general environment and in human fat. In theory the routes of entry into food are ... 

Dioxins and polychlorinated biphenyls (PCBs) in fatty foods, methylmercury in fish, tetrabutyltin in molluscs or fumonisins in com products are some examples of chemical contaminants. Frequently problems concerning chemical contaminants in food reach the headlines of major newspapers and the reader may be left with a scare, sometimes with good reason, often not. In any event, those responsible for the sale of foods must be alert. They bear the responsibility for the safety of the foods they offer for sale, and they also know that any such alert may instantly influence the sale, whether the problem raised is more or less serious. 

The literature on epidemiologic findings is surveyed in other chapters of this book and elsewhere ( 5-7). As a summary, studies on food poisoning episodes have shown that the ingestion of alkylmercury and food oil contaminated by technical polychlorinated biphenyls leads to congenital defects in the offspring. It also appears to be relatively well proven that... 

Bloomington, Indiana Polychlorinated biphenyls (PCB s) Industrial waste contaminating municipal sewage used for garden manure Direct contact and possibly food chain... 

Wu, J.-P, Luo, X.-J., et al. (2009) Biomagnihcation of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls in a highly contaminated freshwater food web from South China. Environmental Pollution, 157(3) 904-909. 

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