Kép forrása BME ABÉT Leírás szerzője VE The duckweeds are removed from each beaker on the 7th day and dried on filter paper until reaching a constant weight. Duckweed (Lemna minor) growth inhibition test (based on frond counts and chlorophyll content) for ecotoxicity assessment of water samples (surface and groundwater, leachate and waste water) according to OECD 221