Maletzki D.,Okotoxikologielabor |
Hunken A.,Okotoxikologielabor |
Hubner I.,Okotoxikologielabor |
Umweltwissenschaften und Schadstoff-Forschung | Year: 2010
Background, aim, and scope The use of plant protection products is common practice in modern agriculture and forestry. Their use, however, may result in risks for the environment because even correct application can not always prevent a possible contamination of the off-field environment. A contamination of surface waters may occur through driftage, precipitation, run-off and drainage from treated surfaces. Dicotyledonous macrophytes are not part of the initial risk assessment of plant protection products in the aquatic environment although they are an important part of the ecosystem. This paper presents a standardised single-phase test system with the dicotyledonous water milfoil Myriophyllum spicatum (Haloragaceae). Methods In order to obtain substance-specific ecotoxicity data, a single-phase test system without sediment was chosen, in order to obtain results that are independent of the distribution of the test substances between water and sediment. The exposure of the test-plants only in the water phase reduces time and effort for analytics and facilitates modelling of the results. Also, a direct comparison with results from investigations with the monocotyledonous duckweed Lemna spec. (OECD Guideline 221) is possible: Ecotoxicity tests on Lemna spec. represent a standard test system for herbicides. Results, discussion, conclusions Myriophyllum spicatum is exposed for 14 days under axenic conditions in a climatised incubator. Ecotoxicity in terms of growth inhibition in Myriophyllum spicatum is determined as a dose-responsecurve. Growth inhibition is determined by measuring the length of the main shoots, the side shoots and the roots as well as determining the plants' fresh and dry weight. This paper describes the design of the Myriophyllum spicatum test system and includes results with 3,5-Dichlorophenol. © Springer-Verlag 2010.