Registration Dossier

Diss Factsheets

Ecotoxicological information

Short-term toxicity to fish

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Leuciscus idus (Golden orfe), OECD 203, LC50(96h) : 420 mg/L

Key value for chemical safety assessment

Fresh water fish

Fresh water fish
Effect concentration:
420 mg/L

Additional information

The acute toxicity to fish of the test item was tested according to OECD guideline 203 and EU Method C.1 in a semi-static freshwater test with golden orfe (Leuciscus idus) as test organisms, which is a freshwater fish representative of a wide variety of natural habitats, and can therefore be considered as an important non-target organism in freshwater ecosystems (Wetton, 1996). The study was conducted under certificated GLP compliance. The test concentration to be used in the definitive test was determined by a preliminary range-finding test. Based on these range-finding study, the definitive test was conducted at concentrations of 100, 180, 320, 560 and 1000 mg/L. For both purposes the test material was prepared by direct dispersion in dechlorinated tap water. The acclimatisation period of the juvenile fish was conducted for 7 days. The stock fish were fed commercial Tetramin® flake food which was discontinued 48 h prior to the start of the definitive test. There was no mortality in the 7 days prior to the start of the test and the fish had a mean standard length of 5.4 cm (sd = 0.3) and a mean weight of 1.54 g (sd = 0.38) at the end of the definitive test. The test vessels were covered to reduce evaporation and maintained at 21 +/- 1 °C with a photoperiod of 16 h light and 8 h darkness for a period of 96 h. The test vessels were aerated via narrow bore glass tubes. A semi-static test regime was employed involving a daily renewal of the test preparations to ensure that the concentrations of the test material remained near nominal and to prevent the build up of nitrogenous waste products. The water temperature, pH and dissolved oxygen concentrations were recorded daily throughout the test.Theresults of the definitive study showed the highest test concentration resulting in 0% mortality to be 320 mg/L, the lowest test concentration resulting in 100% mortality to be 560 mg/L and the No Observed Effect Concentration (NOEC) to be 180 mg/l. The No Observed Effect Concentration is based upon zero mortalities and the absence of any sub-lethal responses to exposure at this concentration.The only sub-lethal response to exposure (other than death) was observed at test concentrations of greater than 180 mg/L. This response was fish swimming at the surface.

The 96-Hour LC50 based on nominal test concentrations was 420 mg/L with 95% confidence limits of 320 - 560 mg/L. The No Observed Effect Concentration was 180 mg/L.

The LC50 value of 420 mg/L (420 ppm = 4.2 x 10-4) corresponds to an evaluation number (Bewertungszahl BWZ) for the German Water Hazard Classification Scheme of 3.4.