Reaction Mass of (1R)-1-[(1S)-3,3-dimethylcyclohexyl]ethyl formate and (1R,2S)-2,6,6-trimethylcycloheptyl formate

Short-term toxicity to fish

Description of key information

An OECD TG 203 guideline study in compliance with GLP with carp (Cyprinus carpio) is available for the test substance. Fish (7/dose) were exposed to nominal concentrations ranging from 4.6 to 100 mg/L under semi-static conditions for 96 hours. Since the test substance was volatile the study was performed in air-tight vessels and the media were not aerated. Test substance concentrations were analytically determined and expressed as mathematical means of the concentrations of the test substance measured in the samples taken during the first (t = 0 - 24 h) and the last refreshment period (t = 72 - 96 h). The average exposure concentrations were calculated to correspond with 2.6, 4.9, 13, 34 and 39 mg/L for the WAFs prepared at 4.6, 10, 22, 46 and 100 mg/L, respectively. The test substance induced no lethal effects in carp at or below a WAF prepared at a loading rate of 10 mg/L with an average exposure concentration of 4.9 mg/L (NOEC). At a concentration of 13 mg/L, 100% mortality was observed within 24h after exposure. At the two highest concentrations 100% mortality was observed within 3h after exposure. No clinical abnormalities were seen in the control and the lowest concentration tested. At an average concentration of 4.9 mg/L, all fish from 3-48 h showed discolouration and hypoactive swimming and in addition occasional tottering after 72-96 h. From an average concentration of 13 mg/L fish showed immobility and loss of righting reflex within 3 h after exposure. The study met the acceptability criteria prescribed by the protocol and was considered valid. The 96-h LC50 value is 8.0 mg/L (95% C.L. is 4.9 -13 mg/L).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

8 mg/L