Fusel oil

Short-term toxicity to fish

Description of key information

LC50 (96 h) > 120 mg/L

Additional information

Studies on the acute toxicity to fish are available for two of the four main constituents of Fusel oil.

The key study available for 2 -Methylbutanol (CAS No. 137-32-6) was conducted according to the OECD Guideline 203 under GLP conditions (BASF, 2011). Zebrafish (Danio rerio) were exposed for 96 h under semi-static conditions to a nominal test concentration of 120 mg/L in a limit test. The test concentration was analytically verified, resulting in a mean measured test concentration of 112 mg/L. No mortality or other adverse effects could be observed at the end of the exposure period. Therefore, a LC50 value could not be calculated and it is considered to be > 120 mg/L (nominal).  

The key study carried out with Ethanol (CAS No. 64-17-5), was performed following the US EPA Method E03 -05 under non-GLP conditions (Brooke et al., 1984). Fathead minnows (Pimephales promelas) were exposed in a flow-through system over a period of 96 h to the nominal test concentrations 0, 4.1, 6.9, 11.5, 19.1 and 31.8 g/L (corresponding to mean measured concentrations of 2.3, 5.7, 9.35, 17.8 and 32.6 g/L). The LC50 -value was determined to be 15.3 g/L based on measured concentrations (arithmetic mean).

Further supporting studies are available for Ethanol (CAS No. 64-17-5) on different freshwater species. All studies indicate low acute toxicity of the substances to fish.

As no experimental results on the acute toxicity to fish are available for 3-Methylbutanol (CAS No. 123-51-3) and 2-Methylpropanol (CAS No. 78-83-1) QSAR-calculations were performed for these constituents as well as for the remaining two major ones. The LC50 (96 h) values determined by using ECOSAR v1.00 as well as the experimental results are presented in the following table.

Constituent of Fusel oil	CAS-No.	LC50 [mg/L]	Reference
Ethanol	64-17-5	15,300	Brooke et al. 1984
		2718,669	ECOSAR v1.00
2 -Methylpropanol	78-83-1	693.96	ECOSAR v1.00
3 -Methylbutanol	123-51-3	305.13	ECOSAR v1.00
2 -Methylbutanol	137-32-6	> 120	BASF SE 2011
		305.13	ECOSAR v1.00

 

The QSAR data indicate low toxicity of all main constituents to fish. They also demonstrate the similarity of the toxic potential between the two isomers 3 -Methylbutanol and 2 -Methylbutanol, and that 2-methylpropanol is expected to be even less toxic. The available data is thus considered to adequately describe the toxicity of all main constituents.

Concluding from the results reported for the main constituents Ethanol, 2-Methylpropanol, 2-Methylbutanol and 3-Methylbutanol, no short-term effects of Fusel oil on fish are expected.