Schadstoffbelastung durch Persorption von Bodenpartikeln

The term persorption describes the paracellular uptake of particles from the digestive tract. It has been shown that solid, hard microparticles such as starch granules, cellulose particles, fibres and crystals are incorporated from the digestive tract. It is likely that an uptake of soil contaminants may also occur via this mechanism, thereby increasing the health risks of children through soil ingestion. The aim of this study was to evaluate the significance of such soil contaminant absorption via this mechanism using data from the literature. Since no information was available on the persorption of soil particles, studies using other models had to be evaluated. The results of these studies show that a persorption of soil particles must be expected. The maximum persorption rate occurs for diameters of <35 μm which is in the range of diameters of street dust, clay and coarse clay. The persorption of these particles is therefore of significance. Data from the literature, however, does not allow an estimation of the magnitude of persorption of such soil particles. Basically, it is conceivable that a relevant ingestion of less mobile pollutants is possible through their persorption in the gastrointestinal tract. Aside from an increased internal exposure via the persorption of soil particles carrying contaminants, additional health risks may occur through the long-term deposit of such particles, the presence of potential allergens as well as through the embolisation of small vessels.     

A new enzyme immunoassay for PCDD/F TEQ screening in environmental samples: comparison to micro-EROD assay and to chemical analysis.

A new Enzyme ImmunoAssay (EIA) for PCDD/F TEQ measurement in extracts of environmental samples was described. The bioassay TEQ which derived from EIA and EROD were compared with each other and with results from chemical analysis. For all environmental samples, the EROD-TEQ is higher than the value from chemical analysis. However, the EIA-TEQ is much more identical with the value from chemical analysis. Our results indicate that the EIA assay is a complementary method to the EROD assay and should be useful as a rapid and sensitive screening tool for environmental samples in many situations.     

Enhanced growth and reproduction of Caenorhabditis elegans (Nematoda) in the presence of 4-nonylphenol

The nematode Caenorhabditis elegans was exposed over a whole fife-cycle (72 h) to several concentrations of 4-nonylphenol (NP; nominal concentrations: 0-350 microg/l). Growth and reproduction of C. elegans were enhanced at NP concentrations of 66 and 40 microg/l, respectively, with effects showing dose-response relationships. These stimulatory effects might be of ecological relevance in benthic habitats, where organisms can be exposed to high concentrations of NP.