1,1'-dithiobis[hexahydro-2H-azepin-2-one]

Short-term toxicity to aquatic invertebrates

Description of key information

EC50(48h) > 100 mg/L
NOEC(48h): 100 mg/L 

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

The acute toxicity to aquatic invertebrates of the test substance was tested according to OECD Guideline 202 and EU Method C.2 in a static freshwater test with Daphnia magna as test organisms, which is a freshwater invertebrate representative of a wide variety of natural habitats, and can therefore be considered as an important non-target organism in freshwater ecosystems (Wetton and Mullee, 2001). The study was conducted under certificated GLP compliance. In-house laboratory cultures of the test animals were used, whereby young daphnids, less than 24 h old were used for testing. These daphnids were not individually identified and received no food. The test concentration to be used in the definitive test was determined by a preliminary range-finding test. Based on this range-finding study, the definitive test was conducted as "limit test" with a single substance concentration of 100 mg/L. Four duplicates were prepared for each test group, two replicates for the control. No aeration was performed and no evidence of undissolved substance was observed, since all preparations were clear, colourless solutions. These solutions were not renewed during the exposure period. The vessels were covered to reduce evaporation and maintained at 21 °C in a temperature controlled room with a photoperiod of 16 h light and 8 h darkness with 20 min dawn and dusk transition periods for a test duration of 48 hours. No reference substance is required in accordance to the test guideline. The EC50 value was determined to be greater than the test concentration of 100 mg/L. The corresponding No Observed Effect Concentration (NOEC) is 100 mg/L. High Performance Liquid Chromatography (HPLC) was the analytical method of choice.