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Heterogeneous reactions of halogen containing species on sulfuric acid aerosol mimics
1998
Beichert, P. | Schrems, Otto
Global policy on sustainable agriculture: a 2020 vision
1998
Pinstrup-Andersen, Per | Pandya-Lorch, Rajul
Risk assessment of conventional crop plants in analogy to transgenic plants
1998
Torgersen, Helge | Soja, Gerhard | Janssen, Ines | Gaugitsch, Helmut
The risk assessment of genetically-modified plants pursuant to Annex II B of EU Directive 94/15/EC assumes that it is possible to infer the environmental impacts of a crop plant from its characteristics, so most of Annex II should also be applicable to conventional plants. To test this, we surveyed reports on the ecological impacts of the cultivation of non-transgenic crop plants with novel or improved traits and, in three cases, investigated whether Annex II B would have been adequate to indicate the effects. Such an assessment appears to be feasible only if the time frame on which it is based is short, so that long-term effects cannot be assessed. Secondly, the plant must be genetically homogenous which is not always granted, e.g. with forest-trees. Thirdly, the cultivation area must be defined. Differences in the behaviour of foreign plants between their original and cultivation habitats may be ecologically relevant and should be assessed. In the (few) cases where direct inference of the observed effects was possible from inherent traits, these effects often correlated with poor adaptation to local environmental conditions. The ecological impacts of traits that had been introduced in order to overcome poor adaptation may differ widely according to the way in which the traits are exploited. In practice, the effects of agricultural measures are more important than the effects of gene transfer and invasiveness, although the latter currently play a major role in risk assessment. In the light of these deliberations, a modification of Annex II B of EU Directive 94/15/EC is suggested.
Show more [+] Less [-]Research Articles Metabolism of phenanthrene in cell suspension cultures of wheat and soybean as well as in intact plants of the water mossFontinalis antipyretica : A comparative study
1998
Schrenk, Christiane | Steinberg, Christian E. W.
The metabolism of phenanthrene was studied both in cell suspension cultures of wheat (Triticum aestivum) and soybean (Glycine max), and in intact plants of the water mossFontinalis antipyretica. Metabolism in cell suspension cultures strongly differed between the monocotyle and the dicotyle plant. Only small amounts oftrans-phenanthrene-9,10-dihydrodiole and phenanthrene-9,10-dione were detectable in the wheat culture. Soybean cultures, in contrast demonstrated a strong turnover resulting in a 75% reduction of the initial phenanthrene concentration. Metabolites were phenanthrene-9,10-dione, not further characterized polar metabolites and bound residues. Intact plants ofFontinalis antipyretica metabolized only small amounts of phenanthrene. Data obtained from cell cultures did not provide information for the metabolic potential in intact plants. Therefore standardized tests with model systems like suspension cultures lead to inadequate assessment of the ecological risk of certain xenobiotics.
Show more [+] Less [-]Determination of chemical warfare agents : Gas chromatographic analysis of ethylarsine dichloride by derivatization with dithiols (3rd Communication)
1998
Haas, Rainer
Ethylarsine dichloride was used during WW I as a chemical warfare agent. Residues of this chemical warfare agent and its metabolites are still present today and continue to contaminate soil and water.A gas Chromatographic method for the detection and determination of ethylarsine dichloride is shown. Six dithiols were tested as possible derivatization reagents for ethylarsine dichloride. With selection of the dithiol, matrix interferences can be eliminated because of the different retention times of the derivatives.
Show more [+] Less [-]Antiestrogenic activity of anthropogenic and natural chemicals
1998
Navas, José María | Segner, H. (Helmut)
A number of natural and man-made chemicals possess antiestrogenic activity, i.e. they antagonize a broad spectrum of estrogen-induced responses in vertebrates. Examples of antiestrogens include dioxin, furan and PCB congeners, certain PAHs, pesticides and indol-3-carbinol derivatives. Major mechanisms of antiestrogenicity are antagonistic action of chemicals at the estrogen receptor, or binding of chemicals to the arylhydrocarbon (Ah) receptor and subsequent interaction with estrogen-responsive genes. Toxicological consequences resulting from antiestrogenic activity have not been conclusively demonstrated to date, although antiestrogenic compounds could critically affect sensitive reproductive and developmental processes.
Show more [+] Less [-]Mercury in precipitation and its relation to bioaccumulation in fish: a literature review
1998
Downs, S.G. (Imperial Coll. of Science, Technology and Medicine, London (United Kingdom). Imperial Coll. Centre for Environmental Technology) | Macleod, C.L. | Lester, J.N.
Soluble carbohydrates and secondary phytochemicals in Betula as affected by SO(2)-pollution
1998
Lavola, A. (Joensuu Univ. (Finland). Dept. of Biology)
Behaviour and impact of cow slurry beneath a storage lagoon. 1. Groundwater contamination 1975-1982
1998
Withers, P.J.A. (Bridgets Dairy Research Centre ADAS, Winchester, Hampshire (United Kingdom).) | McDonald, H.G. | Smith, K.A. | Chumbley, C.G.
Phenolic pattern of bean (Phaseolus vulgaris L.) as an indicator of chronic ozone stress
1998
Biolley, J.P. (Pau et des Pays de l'Adour Univ., Pau (France). Lab. d'Ecologie Moleculaire) | Lauga, B. | Cagnon, C. | Duran, R. | Salvado, J.C. | Goulas, P.