Publications by authors named "W Mathar"

To study the time trend of PCDD, PCDF and dl-PCB levels in the muscle of herring from the Western Baltic Sea, samples were collected in 2006 at the same fishing locations as in 1999. The results demonstrated no obvious change in contamination levels based on content in fat during the last 7 years. The site-dependent increase in WHO-PCDD/F-PCB-TEQ concentrations already found in 1999 in fishing grounds between the Skagerrak and the east of Bornholm could be confirmed by this study.

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During the preparation of cooked foods acrylamide is formed from asparagine and reducing sugars at high temperatures. By-products of oil, starch and sugar production, which may be found in animal feed, partially result from processing steps using heat treatment that are similarly likely to form acrylamide. Possibly, pelletizing during the processing of mixed concentrates may also be involved in acrylamide formation.

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After the publication of high levels of acrylamide (AA) in food, many research activities started all over the world in order to determine the occurrence and the concentration of this substance in various types of food. As no validated methods were available at that time, interlaboratory studies on the determination of AA in food were of the highest priority. Under the boundary conditions of applying well-established evaluation schemes, the results of 2 studies conducted by the Federal Institute for Risk Assessment (BfR) in Germany and by the European Commission's Directorate General Joint Research Center (JRC) exhibited an overall acceptable performance of the participants in these studies.

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Toxic equivalency factor (TEF) has been proposed to estimate the risk of polychlorinated biphenyl (PCB) congeners. However, ortho chlorine substitution in the two phenyl rings gives each PCB its own pattern of toxicity which is different from the mechanism of action of 2,3,7,8-tetrachlorodibenzo-p-dioxin. The present study evaluated the effect of prenatal and postnatal exposure to a low dose of the mono-ortho pentachlorobiphenyl PCB 118 on thyroid hormone concentrations and EROD activity in rats.

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The levels of polychlorinated dibenzo-p-dioxins (PCDDs) and -furans (PCDFs), polychlorinated biphenyls (PCBs), and other organochlorine compounds were determined in a pooled sample of breast milk from 40 mothers (first lactation: 33; second lactation: 7, age: 15-38 years) living in the urban area of Rio de Janeiro County, Brazil, in 1992. Mothers were breastfeeding only one infant and milk was collected between 4 and 6 weeks after delivery. The results showed a dioxin equivalent concentration of 8.

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