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(13-06) Infracor-Gas exposure test on plants - a new method to detect phytotoxic effects via air. Enste-Diefenbach, Ruth*,1, Scholz, Norbert2, 1 Infracor GmbH, Analytical Technical Services, Biology, Paul-Baumann-Strasse 1, 45764 Marl, Germany2 Oxeno Olefinchemie GmbH, Product Safety, Paul-Baumann-Strasse 1, 45764 Marl, Germany ABSTRACT- Infracor-Gas exposure test on plants - a new method to detect phytotoxic effects via air. Enste-Diefenbach R.1 and N. Scholz2. 1 Infracor GmbH, Analytical Technical Services, Biology, Marl, Germany; 2 Oxeno Olefinchemie GmbH, Product Safety, Marl, Germany. On the basis of OECD 208 Test Guideline (July 2000 draft) a new test system is developed to detect phytotoxic effects of chemicals via air stream. This test system can be used as a screening method and a first step in a test hierachy for the assessment of environmentally relevant phytotoxic effects and risks. The test is completely carried out indoors in temperature, light, and humidity controlled growth chambers. It starts with a pre-exposure or germination phase without dosing of test item. Seeds of different plant species, moncotyledonous and dicotyledonous, are used, i. e. different Brassica species, oats, lettuce, cress and wheat. This pre-exposure phase lasts until the plants have reached the minimum length for the test or until the appearance of the first mature leaf. Then, the exposure phase is started by continuously and stable dosing of the test item vapor inside the test chambers produced and maintained by a special delivery system. Control chambers supplied with pure air instead of the test item are kept in parallel under identical conditions. During this phase the concentration of the test item is determined regularly with suitable analytical methods to ensure consistent vapor-phase concentrations. After an exposure period of approx . 3 weeks the test is terminated and evaluated. Test endpoints include above ground wet and dry weight and visual observations. Beside the description of the purpose and the detailed principles of the test system some concentration curves will be presented to show the stability of the vapors produced by our delivery system during the exposure phase as well as some experimental results and evaluations. Key words: phytotoxicity, gas exposure test |
